Biomedical Art Pictorial • Dolphin Social Lives • Plagiarism by Peer Reviewers • Seafaring Spiders Volume 38 | Number 6 NOV/DEC 2017 | $9.95
Reconstructing Neandertal Life Fossilised dental calculus reveals a surprising level of sophistication
Antarctic Clues to the Origin of Viruses The Light Bulb Moment for the Infant Brain The Global Collapse of the Oncology Market Questionable Evidence for Brain Training Programs Gravitational Waves from Colliding Stars • Why Termites Swapped Trees for Mounds
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CONTENTS
FEATURES 14
18 20
22 24
27
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Neandertal Life Reconstructed One Bacterium at a Time
Laura Weyrich Fossilised dental calculus is revealing that Neandertals weren’t the oafish brutes we’ve long considered them to be.
The Light Bulb Moment for Brain Development
Geoffrey Goodhill & Lilach Avitan Some elegant experiments in zebrafish have revealed how sensory experience during infancy can have long-lasting effects on the brain.
Brain Training: Show Me the Evidence!
14
Tejal M. Shah & Ralph N. Martins Many computer-based brain-training programs promise to improve cognitive capacity and delay age-related issues such as Alzheimer’s disease, but how credible is the evidence behind these claims?
Along Came a Spider
Sophie Harrison Genetic studies reveal that trapdoor spiders colonised Kangaroo Island after surviving a remarkable rafting journey from South Africa.
Cathedrals in the Desert
Nathan Lo Termite mounds populate the northern Australian landscape like miniature skyscrapers, yet genetic analyses reveal that the first termites that rafted to our shores originally built their nests in trees. Why did they do this?
18
The Global Collapse of the Oncology Market
Martin Ashdown A new approach to cancer treatment promises the use of fewer drugs and shorter treatment periods, leading to a “big short” of stocks that profit from oncology.
The Art of Science
The Walter and Eliza Hall Institute has created an exhibition of gorgeous images revealing biological processes such as a mammary gland during lactation, deadly parasites that resemble neon flowers, and what happens when you grow a lung in a laboratory.
32
The Secret Life of Dolphins
36
A Plasmid Goes Viral
27
Heidi Pearson & Gabriel Machovsky-Capuska New underwater camera technology has captured the social lives of wild dolphins for the first time, revealing how deep and for how long they dive, how they nurture their young and even how they play with objects in the ocean.
Rick Cavicchioli & Susanne Erdmann No one really knows how viruses evolved, but scientists looking for Antarctic viruses from extremely cold and salty lakes have discovered new clues.
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CONTENTS
conSCIENCE 39
Appropriate Behaviour?
Plagiarism by academic reviewers is hard to prove, and even harder to punish.
NEWS & COLUMNS 5
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Up Front
Australia’s space industry has been adrift in a vacuum of national neglect for more than 20 years, but that is about to change.
Browse
A round-up of science news from our shores.
Neuropsy
A popular fictional theme, psychogenic amnesia is a possible consequence of stress or trauma.
The Fossil File
The Cambrian explosion of animal diversity, evident at the Burgess Shale fossil site is fertile ground for philosophers to ponder.
Expert Opinion
Elon Musk provided an update on his quest to colonise Mars at the International Astronautical Congress in Adelaide, where he described a reusable rocket to overcome cost barriers and an ambitious schedule to land cargo missions on Mars by 2022.
The Bitter Pill
The Chinese government is behind efforts to promote Traditional Chinese Medicine despite its lack of evidence.
The Naked Skeptic
The same sex marriage survey repeats the statistical mistakes of most opinion polls.
EcoLogic
Collaborative wildlife gardening programs engage residents to manage their land and achieve landscape-focused conservation goals.
Lowe Tech
The re-establishment of an Australian space agency is expected to generate billions of dollars after decades of neglect of the sector.
Out of this World
New research supports the view that meteorites kickstarted life on Earth, and Australian astronomers have measured how a galaxy’s spin affects its shape
Quandary
Botched executions provide a timely warning that assisted suicide does not necessarily lead to a peaceful death.
Australasian Sky
Your maps of the night sky for November and December.
UP FRONT
Lost in Space Australia’s space industry has been adrift in a vacuum of national neglect for more than 20 years, but that is about to change. It’s an exciting time for anyone who dreams of worlds beyond our own. Since the last issue of Australasian Science we’ve seen Cassini’s heroic death plunge through Saturn’s rings and the detection of gravitational waves released from the collision of two neutron stars (see p.6). Australian astronomers have played their roles in these events by collaborating with international colleagues and hooking into the data generated by phenomenal new observing facilities abroad and in space. Australia may also be gearing up as a key player in the development of astronomy projects as large as the Square Kilometre Array, but Dr Lee Spitler of Macquarie University says the wider space industry “has largely been operating as a grassroots movement across a small number of companies, university groups and the defence sector”. In space no one can hear you scream, and Australia’s space industry has been abandoned in a vacuum of government indifference for two decades. In 1987 the Labor government created the Australian Space Office to coordinate and commercialise the sector. Some of the big plans floated were a space port on Cape York and the re-establishment of the Woomera rocket launch facility. However, only 9 years later the incoming Howard government dismantled the ASO. Since then it’s estimated that the space industry has grown by 10% per year and is now worth $420 billion each year globally – but only $3–4 billion per year in Australia. This is despite Australia’s history as the third country to construct and launch a satellite 50 years ago, and important observing roles in NASA’s Apollo program. Even now a radio dish just north of Perth tracks every European Space Agency launch and sends instructions to ESA’s fleet of spacecraft. After being lost in space for 21 years, the Coalition government has now announced plans to re-establish a national space agency. However, the formal details of the proposal remain nebulous. The government won’t determine the space agency’s charter until next March, when a review of Australia's space industry capabilities, chaired by former CSIRO chief Dr Megan Clark, tables its report. Even then, Prime Minister Malcolm Turnbull has said the agency will be “small”. We’ll have to wait until next May’s federal Budget to find out how much he’s prepared to back the space industry to contribute to the government’s “Ideas Boom”. While the space industry will be holding its breath until the government breathes some oxygen into the existing vacuum of support for the sector, they’re excited by the opportunities that will soon be within reach. For a start, the space agency would be able to coordinate Australian expertise, establish formal agreements with other nations, and establish initiatives encouraging education and training, research, innovation and business development. Not only will our brightest lights be able to shoot for the stars, but STEM students will see opportunities to launch exciting and stable careers in the space sector without having to move abroad. Guy Nolch is the Editor and Publisher of Australasian Science.
Cover Story
Fossilised dental calculus is revealing that Neandertals were more sophisticated than we give them credit for (see p.14). Credit: Camilo Maranchón García /123RF
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NOV/DEC 2017 |
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Compiled by Guy Nolch
be at the top of your game to play in this space. It is intense, time-critical science.” The team used CSIRO’s Australia Telescope Compact Array to monitor the gravitational wave event for more than 40 hours over several weeks. The results are included in a Science paper, with follow-up observations by other international teams published in several science and astronomy journals simulateneously. Dr Christian Wolf said his team at the Australian National University used the SkyMapper and 2.3metre telescopes at the ANU Siding Spring Observatory as part of the search for other signals from the neutron star collision. “We saw the light from a fireball blasting out from the neutron star collision into space in the hours and days afterwards,” he said. “SkyMapper was the first telescope to report the colour of the fireball, which indicates the temperature of the fireball was about 6000°C – roughly the surface temperature of the Sun.” Prof Matthew Bailes of the ARC Centre of Excellence for Gravitational Waves (OzGrav) – a collaboration of Australian universities participating in the LIGO Scientific Collaboration – said: “Never before have we seen where in the universe gravitational waves came from; the subsequent avalanche of science was virtually unparalleled in modern astrophysics”. The research has been published in Physical Review Letters, Nature and Astrophysical Journal Letters. Prof Susan Scott, who is Leader of the General Relativity Theory and Data Analysis Group at ANU, said gravitational waves would unlock many secrets of the universe. “This discovery of neutron stars colliding is just the beginning. We want to one day look back to the beginning of time – just after the Big Bang, which we can’t do with light. “This is the first time that the collision of two neutron stars has been detected, and this is the closest and most precisely located gravitational wave signal we’ve received. It is also the loudest gravitational wave signal we’ve detected.” Neutron stars are the densest stars in the universe, with a radius of about 10 km. Scott said neutron star mergers were likely to be the site where much of the universe’s heavy metals such as gold, platinum and uranium are produced. “With this discovery we have the opportunity to learn so much more about neutron stars, which have been quite a mystery to us,” she said. “Unlike black holes, neutron star collisions emit other signals such as gamma rays, light and radio waves, so astronomers around the world were able to observe the event through telescopes. This is an amazing time to be a scientist.” Prof David McClelland of the ANU Research School of Physics and Engineering is leading a team that is developing new components and techniques for the LIGO detectors. “Using quantum mechanical techniques, we will make the largest optical sensors ever built even more powerful. We will then detect many more gravitational waves from cataclysmic events in space, involving black holes, neutron stars and things not yet known. All of this paints an incredibly bright future for the field.” Credit: LSCSonoma State UniversityAurore Simonnet
BROWSE
An artist’s impression of the two neutron stars colliding.
Gravitational Waves Detected from Two Stars Colliding Australian astronomers have confirmed the first-ever detection of gravitational waves produced by the collision of two neutron stars about 130 million light-years away in galaxy NGC 4993. The explosion was detected by NASA’s Fermi gamma ray telescope about 2 seconds after the gravitational wave was detected by the US-based Laser Interferometer Gravitational-wave Observatory (LIGO) and Europe-based Virgo Collaboration. Visible light and gamma-ray emissions allowed astronomers to pinpoint the location of the collision. The first follow-up detection was optical about 11 hours after the event, and was observed by a number of groups worldwide. X-ray emissions were detected 9 days later and radio waves after 15 days. A/Prof Tara Murphy of The University of Sydney, who led the radio astronomy follow-up in Australia, said she was in the United States when the gravitational wave discovery was announced on LIGO’s private email list. “We immediately rang our team in Australia and told them to get onto the CSIRO telescope as soon as possible, then started planning our observations,” she said. “We were lucky in a sense in that it was perfect timing but you have to 6|
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Evidence that Climate Change Caused Thylacine’s Mysterious Loss from Australia’s Mainland Researchers from the Australian Centre for Ancient DNA (ACAD) at The University of Adelaide have concluded that climate change from about 4000 years ago, in particular more drought-prone seasons caused by the onset of the El Niño Southern Oscillation, was the likely main cause of thylacine extinction on the Australian mainland. The ACAD study, published in the Journal of Biogeography, also reported evidence from ancient DNA extracted from fossil bones and museum specimens that a large and genetically diverse population of thylacines lived in western regions of Australia right up to their extinction from the mainland around 3000 years ago. “The thylacine was a marsupial carnivore, now infamous for its recent humandriven extinction from Tasmania following the arrival of Europeans and their bountyhunting schemes,” says project leader A/Prof Jeremy Austin. “Thylacines once lived across most of A thylacine fossil jaw bone from the Tasmanian Museum and Art Gallery. Credit: Jeremy Austin, University of Adelaide the Australian mainland, but by the time Europeans arrived in the late 1700s they were found only in Tasmania. They became extinct about 150 years later, with the last of the species dying in Hobart Zoo in 1936. “But the reasons for their disappearance from mainland Australia and continuing survival in Tasmania has remained a mystery.” Climate change, increased human activity and the introduction of the dingo are the three main causes debated. The researchers generated 51 new thylacine mitrochondrial DNA genome sequences from fossil bones and museum specimens – the largest dataset of thylacine DNA to date. This provided the first genetic evidence that mainland thylacines split into eastern and western populations in southern Australia before the last ice age peak of about 25,000 years ago. “We wanted to understand why thylacines went extinct on the mainland but survived in Tasmania,” says lead author and PhD student Lauren White. “The ancient DNA tells us that the mainland extinction was rapid, and not the result of intrinsic factors such as inbreeding or loss of genetic diversity. “We also found evidence of a population crash, reducing numbers and genetic diversity of thylacines in Tasmania around the same time,” Austin says. “This mirrors what happened with another carnivorous marsupial, the Tasmanian devil, which still lives in Tasmania. Unlike the devil, however, it appears that the population of thylacines was expanding at the time of European arrival. “Tasmania would have been somewhat shielded from the warmer, drier climate because of its higher rainfall, but it appears that this population was also affected by the El Niño event before starting to recover.”
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Australia’s Giant Flightless Fowl’s Far-Flung Family
Chickens and ducks share their evolutionary roots with the 650-kg Dromornis stirtoni. Credit: Brian Choo
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Australia’s giant mihirungs (Dromornithidae) were flightless fowl that included some of the most massive birds in the world, such as the horse-sized Dromornis stirtoni, which tipped the scales at 650 kg. But what were they related to? In a new analysis published in Royal Society Open Science, palaeontologists from Flinders University and Argentina have revealed that these birds share their evolutionary roots with the giant Gastornis species in the Northern Hemisphere. Together they form a major lost branch on the evolutionary tree of fowl: chickens and ducks. This group lived in Australia from 55 million years ago until becoming extinct about 50,000 years ago. When the last one died an entire taxonomic order, and some of the most spectacular birds ever to have lived, disappeared. How did giant birds disperse across both hemispheres? The scientists suggest that small flying birds gave rise to giant flightless fowl twice – once in Australia and again in the Northern Hemisphere. “They form a neat parallel to how we now understand the ratites (emu, ostrich and kin) evolved,” says study leader A/Prof Trevor Worthy of Flinders University. “At the base of the family tree of giant flightless ratites on each continent we now know there was a small flying bird like a tinamou. These dispersed across the oceans, settled on a continent, evolving into huge and flightless birds. One became moas in New Zealand, another the ostrich, and yet another the emus and cassowary in Australia. Now we see that the giant fowl share a similar history.” Despite their great size, the mihirungs and their Northern Hemisphere relatives were gentle giants. “Mihirungs were herbivores, just like typical ducks and geese,” says co-author Prof Mike Lee of Flinders University and the South Australian Museum. “Despite a 500-fold increase in body size, they retained the diets of their much smaller ancestors,” he says. The team found other surprising relationships. Vegavis, which was previously interpreted as a modern duck from dinosaur-age rocks in Antarctica, was found to be much more primitive, in line with its great age. “This helps bring the fossil history and that inferred from DNA closer together,” Worthy says. Moreover, the extinct flamingo ducks (Presbyornithidae), whose existence in Australia was only recently recognised, were also found to be more primitive than previously believed, and are shown to be the distant cousins of modern geese and ducks. “This makes sense because they evolved long before typical waterfowl and bear little similarity to them,” says co-author Warren Handley, a PhD student supervised by Worthy. However, in a surprising twist the team found that the largest flightless bird of South America, Brontornis, is not remotely related to fowl, as some recent studies had advocated. Instead, this 300 kg giant was actually a slower relative of the terror birds (Phorusrhacidae), which replaced dinosaurs as the supreme predators of South America during the Cenozoic era. “Perhaps the terror birds meant there was no place for sluggish giant fowl in South America. Only the fast-running rheas and kin could live with them,” says co-author Dr Federico Degrange of the Centro de Investigaciones en Ciencias de la Tierra in Argentina.
Forensics Unearth Kimberley Massacres For almost a century, the people of the Kutjungka region in the south-east Kimberley of Western Australia have passed on the testimony of massacres of their ancestors at Sturt Creek. Now Flinders University, CSIRO and other researchers have found scientific evidence that the bodies of Aboriginal victims were frequently incinerated following the event. Working with the oral testimony of the descent group, which originated from Riwarri, the sole adult survivor of the massacre, archaeological surveys defined two distinct sites containing thousands of bone fragments. X-ray diffraction analysis of 16 bone fragments confirmed that the fragments had been subjected to extreme temperatures of 600°C for more than 80 hours, 650°C for more than 20 hours, 700°C for more than 4 hours and 800°C for more than 1 hour. “The oral testimonies were that people were shot and burnt,” says Dr Pamela Smith of Flinders University Archaeology. “The XRD analysis from CSIRO provided the key evidence, because those bone fragments had been subjected to intensely hot fires over a very long time. There had to be people there maintaining those fires and temperatures for a long period. That was the evidence of human intervention.” Macroscopic and microscopic examinations of some of the bone samples found strong pathological and archaeological evidence that the bone fragments were human in origin, although the evidence was not conclusive. The results of the investigation were published in Forensic Science International. This painting illustrates the massacre event. It shows Aboriginal prisoners chained between two trees. The four figures (two left and two right) hold guns. The footsteps end at the well and goat yard, and both contain fragmented bone. The white line and black stones on either side of the creek (Sturt Creek) represent the “milky” coloured water of Sturt Creek and the black stones along the banks are what artist Daisy Kungah described as purrkuji, the jupilkarn (cormorants) in the Dreamtime. Credit: Launa Yoomarri and Daisy Kungah painting under the direction of Clancy and Speiler Sturt (sons of Riwarri). Permission to reproduce the painting was given by the artists at a meeting with the Custodians at Billiluna, August 2010. Source: Kuningarra School, Billiluna Aboriginal Community, Western Australia
Nanopatch Delivers Polio Vaccine Better than a Syringe Efforts to rid the world of polio have taken another significant step with a fresh study showing that the Nanopatch™ – a microscopic vaccine delivery platform first developed by University of Queensland researchers – combats poliovirus more effectively than needles and syringes. Head of UQ’s School of Chemistry and Molecular Biosciences, Prof Paul Young, said the breakthrough provided the next step in consigning polio to history. “Polio was one of the most dreaded childhood diseases of the 20th century, resulting in limb disfigurement and irreversible paralysis in tens of millions of cases,” he said. “This most recent study showed the Nanopatch enhanced responses to all three types of inactivated poliovirus vaccines (IPV) – a necessary advancement from using the current live oral vaccine.” Prof Mark Kendall said the Nanopatch “targets the abundant immune cell populations in the skin’s outer layers, rather than
muscle, resulting in a more efficient vaccine delivery system. The ease of administration, coupled with dose reduction observed in this study, suggests that the Nanopatch could facilitate inexpensive vaccination of inactivated poliovirus vaccines.” Dr David Muller of the Australian Institute for Biotechnology and Nanotechnology said effectively translating the dose could dramatically reduce the cost. “A simple, easy-to-administer polio Nanopatch vaccine could increase the availability of the IPV vaccine and facilitate its administration in door-to-door and mass vaccination campaigns. As recently as 1988, more than 350,000 cases occurred every year in more than 125 endemic countries. “Concerted efforts to eradicate the disease have reduced incidence by more than 99%. Efforts are being intensified to eradicate the remaining strains of transmission once and for all.” The research has been published in Scientific Reports. NOV/DEC 2017 |
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Scorpions Adjust Venom to Predators and Prey Scorpions can fine-tune their venom to suit different predators and prey, a study published in Proceedings of the Royal Society B has reported. Dr Jamie Seymour of The Australian Institute of Tropical Health and Medicine at James Cook University said that varieties of scorpion toxin worked better depending on whether they were used to protect themselves from predators or kill prey. A typical scorpion predator would be a small mammal, while its prey was usually an insect. “Scorpions contain three separate subtypes of toxins that are effective against mammals only, insects only, and both,” Seymour said. The venom produced can be thought of as a cocktail of the different toxins. “The question was whether the ‘recipe’ for this cocktail is fixed or can adapt in response to different environments and predator–prey interactions.” The research team kept Australian rainforest scorpions under different conditions. One group was given live crickets, another was given dead crickets, and a third group was subjected to the threat of a stuffed mouse to simulate a predator threat. After 6 weeks, scorpions exposed to the simulated predator exhibited significantly different venom chemistry compared with those not exposed to predators.
“Exposure to a simulated predator appeared to decrease relative production of toxins that would work on insects, while generally increasing the production of a section of the venom profile with activity towards mammalian cells,” said co-author Dr Tobin Northfield. Seymour believes this is the first time researchers have reported that venom chemistry in organisms can change in response to a threat. “It implies a re-routing of nutritional or energetic resources by the scorpion to increase relative production of different venom fractions which are responsible for toxicity to invertebrates,” he said. Seymour said the finding opened up the potential for improvements in anti-venom design.
Earth’s Magmatic Heart May Be Beating New information about the youngest plutonic rocks found on the Earth will help to pinpoint the timing and recurrence of major magmatic pulses beneath the planet’s surface, according to a study published in Scientific Reports. The research suggests that plutons – the crystallised remnants of magma chambers deep underground – form every 700,000 years within the Hida Mountains of central Japan. This suggests that the next big magmatic pulse may already be happening. Lead researcher Dr Christopher Spencer of the WA School of Mines at Curtin University said the research provides critical insights into understanding how volcanic systems are connected to pulses beneath the Earth’s surface. “The Hida Mountain range in Japan contains the youngest exposed plutonic rocks on Earth, and provided us with a unique opportunity to assess the different characteristics of the tempo of magmatism, or the movement of magma, deep in the Earth,” he said. 10 |
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“Our ability to distinguish two closely-spaced magmatic pulses becomes much more difficult the longer we look back into history, but this discovery now allows us to investigate these instances that otherwise might have been left unanswered.” Spencer said Japan is an ideal location for this research because the magmatism seen in the Hida Mountains falls within a similar time scale as other volcanic systems around the world. “It has been over 700,000 years since the last major magmatic activity in the area, and this work may indicate that more magmatism is forming deep in the Japanese crust at this very moment,” he said. “By analysing the timing and speed of the magmatic pulses deep beneath the surface of the volcanoes, we are able to understand how these systems work from top to bottom. The more we know about the tempo of magma formation deep within the volcanoes, the better we can understand the nature of volcanic activity around the world.”
Cats Kill More Than One Million Australian Birds Per Day Feral cats kill 316 million birds and pet cats kill 61 million birds in Australia every year. More than 99% of these casualties are native birds. The estimates, published in Biological Conservation, are based on results from nearly 100 studies of cat density across the country, and another set of nearly 100 studies that assessed cat diet nationally. Lead researcher Prof John Woinarski of Charles Darwin University said that while previous research has looked at the impact cats are having on Australia’s mammals, this is the first nationwide assessment of the impact of cats on Australia’s birds. “Everyone knows that cats kill birds, but this study shows that, at a national level, the amount of predation is staggering, and is likely to be driving the ongoing decline of many species,” Woinarski said. The study also found that the highest rates of cat predation on birds is on Australia’s islands and in remote arid Australia, where the number of birds killed by cats each year can reach 330 birds per square kilometre. In a second study, the research team also looked at which bird species are at most risk from cat predation. They found records of cats killing 338 native bird species – almost half of Australia’s native bird species. This included 71 threatened bird species. “We found that the birds most likely to be killed by cats are medium-sized birds, birds that nest and feed on the ground, and birds that occur on islands or in woodlands, grasslands and shrublands,” Woinarski said. “For Australian birds, cats are a long-standing, broad-scale and deeply entrenched problem that needs to be tackled more effectively.”
Australia’s Acting Threatened Species Commissioner, Sebastian Lang, added: “Our knowledge of the impacts of cats on threatened mammals was a major stimulus for our first-ever national Threatened Species Strategy, which prioritised actions to control feral cats. This new research emphasises the need to continue working to reduce the impact of cats on our native biodiversity.”
Stellar Shell Explosion Triggers Star Death International astronomers believe they may have observed a precursor explosion that warns observers that a supernova is taking place. Within a day of witnessing this “red optical flash”, the researchers discovered a Type Ia supernova named MUSSES1604D. Type Ia supernovae arise from the thermonuclear explosion of white-dwarf stars that have cores of carbon and oxygen. Follow-up observations carried out by eight telescopes around the world showed that this supernova phase is marked by a bright flash about half a day after the explosion of a type Ia supernova. The astronomers found that the early-phase light, colour and spectrum of the supernova could be perfectly explained by a stellar shell explosion in which the accumulation of helium at the surface of the white dwarf first ignites. Shock waves generated by this precursor event then propagate inward to ignite carbon burning in the core of the white dwarf. The observation is the first robust proof of a stellar shell explosion, which was first proposed in the early 1980s but had not been witnessed until now. “Learning more about type Ia supernovae will help us chart the expansion of the Universe,” said Prof Jeremy Mould of Swinburne University, who was co-author of the report published in Nature.
The small flash at the bottom right of this bright galaxy preceded the observation of a supernova explosion.
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Climate Is Driving Migration
MeTro is applied directly to the wound and activated with light.
Elastic Surgical Glue Seals Wounds in 60 Seconds A highly elastic and adhesive surgical glue that quickly seals wounds without the need for common staples or sutures could transform how surgeries are performed. The highly elastic nature of the MeTro glue makes it ideal for sealing wounds in body tissues that continually expand and relax, and are therefore are at risk of re-opening, such as the heart, lungs and arteries. The material, described in Science Translational Medicine, also works on internal wounds in hardto-access areas or where staples and sutures have been required because the surrounding body fluid hampers other sealants. MeTro sets in just 60 seconds once treated with UV light. It has a built-in degrading enzyme that can be modified to determine how long the sealant lasts – from hours to months – to allow adequate time for the wound to heal. The liquid or gellike material has quickly and successfully sealed incisions in the arteries and lungs of rodents and the lungs of pigs, without the need for sutures and staples. MeTro combines the natural elastic protein technologies developed by co-author Prof Anthony Weiss of The University of Sydney with light-sensitive molecules developed by co-author Prof Ali Khademhosseini of Harvard Medical School. Weiss likened the process to silicone sealants used around bathroom and kitchen tiles. “When you watch MeTro, you can see it act like a liquid, filling the gaps and conforming to the shape of the wound,” he said. “It responds well biologically, and interfaces closely with human tissue to promote healing. The gel is easily stored and can be squirted directly onto a wound or cavity. Khademhosseini said that “MeTro seems to remain stable over the period that wounds need to heal in demanding mechanical conditions, and later it degrades without any signs of toxicity. It checks off all the boxes of a highly versatile and efficient surgical sealant with potential also beyond pulmonary and vascular suture and staple-less applications,” he said. Elastagen Pty Ltd is commercialising the technology, and Weiss said that the next stage for the technology is clinical testing. “We have shown MeTro works in a range of different settings and solves problems other available sealants can’t. We’re now ready to transfer our research into testing on people.” 12 |
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New Zealand researchers have shown that not only are the effects of climate change influencing people’s decision to migrate, it is actually a more important driver than income and political freedom at the origin country. Traditionally, research looking into the drivers of migration focuses on economic differences, such as wages and the costs of migration. It has only recently included climate factors. Dr Dennis Wesselbaum of The University of Otago and Masters student Amelia Aburn of Victoria University of Wellington looked at migration flows between 16 OECD destination countries and 198 origin countries over 35 years. This is the first time data about various potential driving forces of migration, including climatic factors, has been studied over a long time period. Wesselbaum amassed data from each country on significant weather events and temperatures and data on immigration from 1980 to 2014, then modelled immigration flows over that time to determine patterns and identify significant factors. That work showed events like storms, floods, heat waves and droughts have different effects on migration. In particular, temperature rise is having a major influence in immigration decisions; intuitively, people are moving away from the negative effects of climate change. Wesselbaum has also shown that single or unforeseen events, such as storms, can have a long-lasting impact on a country’s immigration figure. Most interestingly, after an increase in temperatures, migration decreases for roughly 4 years before it increases for about 10 years. This presents an important but tight window of opportunity for policymakers, as the speed of the policy response is crucial in limiting the effects of shocks from such events in origin countries, and therefore the effects on migration. “Both developed and at-risk countries need more planning and policy to prepare for what is likely to be a growing trend of people wanting to move from countries experiencing climate change,” Wesselbaum said. “Climate refugees have yet to be recognised officially by international law and included in the UN refugee convention, but the predicted 2–3°C rise in global temperature will see climate refugees rather sooner than later. The discussion paper is at http://tinyurl.com/y88m7uzz
Alcohol-Related Crashes Are Less Likely Near Pubs Motor vehicle crashes are more likely to be alcohol-related if they are further away from on-premise alcohol outlets such as bars and pubs, according to research by the Curtin-Monash Accident Research Centre (C-MARC). The research, presented at the 2017 Australasian Road Safety Conference in Perth, found that a crash was more likely to involve alcohol as the distance to on-premise alcohol outlets increased. Lead author Dr Michelle Hobday of C-MARC said the research “suggests that police enforcement, including random breath testing, should take place closer to residential areas, particularly in the early hours of the morning, as well as near areas containing large numbers of alcohol outlets.”
Lift Less, Gain More The belief that lifting heavy weights is necessary to build muscles is being challenged by evidence that resistance training at low loads with blood flow restriction (BFR) can increase muscle size and strength. “BFR, also known as Kaatsu training, involves performing exercise with a restrictive cuff placed around the exercising limbs,” said Mr Charlie Davids of The University of Queensland’s School of Human Movement and Nutrition Sciences. “This reduces the amount of blood and oxygen delivered to the exercising muscles, leading to an accumulation of metabolic by-products, such as lactate, causing some parts of the muscle to fatigue quickly while others compensate.” Davids said that BFR has potential implications for the injured and elderly, who “often possess musculoskeletal conditions that limit their ability to achieve significant gains in muscle size and strength with normal resistance exercise. The low loads typically used with BFR mean that the muscles and joints are subjected to lower levels of stress, which may accelerate the recovery from musculoskeletal injury, or allow elderly people to combat the natural decline in muscle mass that occurs with ageing.” Davids said that BFR was also showing promise for healthy individuals and athletes. “The reduced training stress may mean a greater number of training sessions can be performed in shorter periods,” he said. “Training sessions could potentially be increased to twice daily, which has been demonstrated to produce marked
Hot Crocs Can’t Hide Long
xangai/Adobe
When frightened, young crocodiles will dive and remain submerged until the threat has passed. However, the length of time they can stay submerged is limited by their metabolic rate, which is expected to rise as water temperatures increase due to climate change. Prof Craig Franklin of The University of Queensland measured how long scared juvenile crocodiles could remain submerged at both current river water temperatures and the temperatures that crocodiles are predicted to encounter in 2100 to find out how these reptiles may fare in the future. After adapting the young crocodiles to current (28°C water) or future (34°C) climate scenarios for 2 months, co-worker Dr Essie Rodgers startled the animals with a gentle tap on the back and timed how long they remained submerged. The crocodiles that were adapted to current climate conditions were content to remain submerged for 18.5 minutes, extending to more than an hour if they felt particularly harassed after performing four consecutive dives.
Reduced training stress may mean a greater number of training sessions can be performed in shorter periods.
increases in muscle size in as short as 2 weeks.” Davids is investigating the responses of healthy individuals to BFR training in an effort to translate the practice to clinical domains. “There is a lack of consensus among scientists, practitioners and coaches as to how this novel exercise method can be adapted to cater for the goals and health considerations of various populations,” he said. “We want to address this gap by assisting with the formulation of evidence-based guidelines for BFR resistance exercise.” However, the hot-water crocodiles could only remain under water for 9 minutes after a single tap on the back, and the more threatened animals only stayed down for 28 minutes. Rodgers also measured the animals’ heart rates and oxygen consumption to try to understand why the hot-water animals’ refuge tactics were so impaired, and found that the crocodiles that had adapted to water at 34°C were unable to lower their metabolism as much as the cooler crocodiles. They were burning through oxygen at a faster rate, forcing them to return to the surface sooner than their cooler cousins. “This finding suggests predator avoidance dives may be shortened if water temperatures continue to increase in marine and freshwater habitats,” warn Rodgers and Franklin, who are concerned that crocodile youngsters will become more vulnerable to predators as they are likely to have to surface more frequently if the temperature continues rising. The research has been published in the Journal of Experimental Biology.
Give the gift of science Put
under a tree this Xmas
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Neandertal Life
Reconstructed One Bacterium at a Time LAURA WEYRICH Fossilised dental calculus is revealing that Neandertals weren’t the oafish brutes we’ve long considered them to be.
ur vision of Neandertals often includes a grunting, club-touting, beastly individual who may or may not be covered in fleas. The Neandertal is likely wearing furs from the animals it killed and is probably looking a bit confused. But is that how Neandertals really were? New evidence from bacteria preserved on their teeth suggests otherwise.
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Why Are Neandertals Portrayed as Oafs? Decades of research have worked to unhinge this perception, but in many cases only reinforced it. Researchers assumed that the Neandertal diet would be a healthy mixture of meat and gathered food items, but when they used isotopes to examine the major food groups for Neandertals, the results suggested they were as carnivorous as polar bears! When researchers looked at artifacts to learn more about their daily lives, they found tools used for hunting large game, further suggesting that Neandertals were running around with spears, 14 |
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clubs and fur cloaks. Other research also suggested that they may have been cannibals, which painted a picture of a mean, oafish lifestyle. Despite these decades of research, this is the equivalent of saying that we know all humans today because we know they ate meat, carried cell phones and wore blue jeans. This shows almost nothing about how humans live their daily lives, and says absolutely nothing about their culture, beliefs or behaviours.
DNA from Oral Bacteria Paint a New Picture We now have a new tool to learn more about ancient hominids and how they once lived – by looking at the bacterial gunk that sticks to their teeth. The slimy, gross feeling that seems to grow on your teeth after you consume a sugary drink is actually millions of bacteria growing in response to the sucrose that you just ingested. If you don’t brush your teeth – as many of our ancestors and cousins did – the bacteria in your mouth become locked in a calcified matrix when you
sleep. This matrix, otherwise known as dental calculus, can preserve microorganisms, diseases and other dietary and environmental microparticles in the mouth for thousands of years. In fact, dental calculus preserves as well as bone in most cases. So wherever there’s an ancient skeleton, there’s a good chance that there will also be an accompanying fossil record of the bacteria and food that was once present in the mouth of an ancient person. We can sequence the DNA preserved from these micro organisms and microparticles in dental calculus to understand more about ancient humans. Perhaps the most telling evidence preserved in dental calculus is the oral bacteria. These incredibly diverse oral bacterial communities (referred to as microbiota) are extremely adaptable and can rapidly respond to changes in their microenvironment, such as changes in a human’s diet, environment, hygiene,
The cmplete jaw of Spy II, with small and thin dental calculus deposits that provided usable DNA sequences. Credit: Royal Belgian Institute of Nature Sciences
Two distinct types of microbiota could be observed within the Neandertals and hunter-gatherers. The type of microbiota found in El Sidron Neandertals was shared with ancient gatherers and chimpanzees, while the type found in Spy Neandertals was shared with individuals who largely based their diet around hunting. In fact, it was the Spy Neandertals that were as carnivorous as polar bears. This split in the microbiota suggests that Neandertals may have been living very different lifestyles, and that these may have corresponded to differences in diet.
health, or even medicine. By sequencing bacterial DNA, researchers can now use ancient oral microbiota to understand more about past human lifestyles, diet and health. In a recent study published in Nature (http://tinyurl.com/ ya5us67p), we applied this new technique to Neandertal dental calculus to learn more about Neandertal’s diet, lifestyle and behaviour. Two Neandertals from Spy Cave in Belgium, two Neandertals from El Sidron Cave in Spain, and one Neandertal from Brueil Grotta in Italy were chosen for this project. Not all Neandertals have dental calculus, and some Neandertals used hygienic practices of tooth-picking to help remove calculus from their teeth. We also selected a wide range of ancient humans and historic apes for comparison.
Neandertals Shared Bacteria with Ancient Humans and Chimpanzees The DNA revealed that Neandertals contained a unique set of oral microbiota that is not shared today with modern humans. Neandertal oral microbiota was shared with chimpanzees and ancient human hunter-gatherers from both Europe and Africa. This finding suggests that Neandertals, humans and chimpanzees once shared a similar set of oral microbiota, and that the microorganisms that once lived in the human mouth coevolved with humans over millions of years.
Could Neandertals Have Been Vegetarians? The difference between meat-eating or simply gathering plantbased foods appeared to separate two groups of Neandertals. To explore the diet and its contributions to oral bacterial diversity further, we looked at DNA from the microparticles that were also preserved in Neandertal dental calculus. These microparticles often correspond to dietary sources, although they can also be non-dietary fragments, such as rope that was cut using the teeth. In the Spy Neandertals, we found evidence of meat-eating that corresponded with previous isotope findings. We found DNA corresponding to woolly rhinoceros (which went extinct in Europe about 38,000 years ago), wild sheep (perhaps like the mouflon sheep that are still present in Europe today) and mushrooms.
El Sidron Tunnel of Bones, where 12 Neandertal specimens dating around 49,000 years ago have been recovered. Credit: Antonio Rosas/Paleoanthropology Group MNCN-CSIC
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as mushrooms. Knowledge of which types of foods to gather, such as edible mushrooms rather than poisonous ones, would have been passed down from generation to generation. Neandertals would have needed a way to interact and share this knowledge with their young ones. This also means that they did not spend all of their days touting clubs and chasing after large game; they likely spent some days holding a basket and gathering mushrooms and nuts from a forest floor. A dental calculus deposit on the rear molar (right) indicates that this El Sidron Neandertal While the idea that we can was eating poplar, a source of aspirin, and had also consumed mouldy vegetation including identify specific food sources Penicillium fungus, a source of a natural antibiotic. Credit: Paleoanthropology Group MNCN-CSIC from Neandertals is incredibly exciting, it is also still early days for this new methodology. Further research needs to be done to verify and authenticate these findings. For example, we know that Neandertal bones were once coated with varnish when they were taken out of the ground – a practice that often helped preserved the bones to later showcase them in museums. Hundreds of years ago, when these bones were being dug up by archaeologists, much of this varnish was made from animal’s hooves, typically goat hooves. As a result we cannot be sure that the sheep DNA identified Spy I Neandertal teeth showing dental calculus deposited as rind on tooth enamel. DNA from the dental calculus revealed that this individual had been eating woolly rhinoceros, mouflon sheep and in Spy Neandertal dental mushrooms. Credit: Royal Belgian Institute of Nature Sciences calculus did not correspond to In contrast, there was little evidence for meat-eating in the the DNA present in the varnish, but we can be sure that the El Sidron Neandertals; DNA corresponding to pine nuts, mush- woolly rhinoceros was not used to make varnish because the rooms and even moss were identified, suggesting that their diet animal became extinct more than 38,000 years ago in Europe. We also know that DNA from bacteria and larger mammals, at the time may have been much more vegetarian than their such as humans, can also be shared, so identifying dietary DNA Spy cousins. Regardless of these differences, the evidence suggests that that corresponds to mammals can be difficult. Dental calculus Neandertals were very much in tune with their environments samples are more than 95% bacterial, which leaves very few and knew where to collect certain foods. The results also suggest DNA sequences that correspond to food. Microbial DNA that even though previous research suggested they were only sequences can also integrate into sources of food DNA, further eating meat, Neandertals were eating plant-based foods such complicating matters. 16 |
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Sequencing DNA from other bones in the cave and from any known dietary sources may provide more clarity, but for now, inferring dietary or non-bacterial information from the DNA in calculus is tough business.
Neandertals and Humans Swapped Bacteria The bacteria in Neandertal mouths can also tell more nuanced stories about a Neandertal’s life beyond their diet, health, traditions and daily behaviours. By looking at the genetic mutations in individual bacteria in Neandertals, we can track their evolutionary history and give evidence to support the origins of specific bacteria in the human body. Several studies have used genomic mutations in microorganism to identify when ancient outbreaks occurred, or to identify the ancient causes of plagues. In this study, one of the El Sidron Neandertals had large amounts of a unique oral microorganism, Methanobrevibacter oralis, present in his mouth. We compared the mutations in the M. oralis genome from Neandertals with those in modern humans, and found that Neandertals obtained this oral microorganism about 120,000 years ago. Neandertals and humans likely diverged about 700,000 years ago, so Neandertals must have obtained this microorganism much later in their evolutionary history; this strain of M. oralis may not have been present in Neandertals since their origins. While highly speculative, this suggests that Neandertals may have obtained M. oralis from either humans or shared environmental sources. We know that modern humans can transfer oral bacteria by sharing food, caring for others or even kissing. While it’s easy to let the imagination run wild and assume Neandertals and humans must have been kissing, it’s just as easy to assume they may have drank from the same water source. It is interesting to note that the origin of this oral microorganism in Neandertals is also about the same time as the earliest cases of interbreeding between Neandertals and humans. Whether or not Neandertals and humans were kissing during interbreeding remains to be seen, but it’s certainly enough evidence to start examining these interactions closer. Analysing more microbial genomes from Neandertals and ancient humans may provide the clues we need to understand how intimate Neandertals and humans were with one another. What Does Knowing More About Neandertals Mean for Me? If Neandertals and ancient human hunter-gatherers once shared a microbiome, what happened to that microbiota in humans today? The study also verified an early finding that modern human oral microbiota was drastically impacted during the onset of agriculture about 7500 years ago in Europe, when readily available carbohydrates became the major food source and lifestyles became more sedentary.
The Spy Cave site in Belgium, from which several Neandertal skeletons were excavated in 1886. Credit: Royal Belgian Institute of Nature Sciences
We also identified another change in the microbiota from ancient humans to today. The evidence also suggested that more recent events, most likely since the Industrial Revolution, have also impacted our microbiota. While researchers are unsure what has caused these recent changes, processed food, pollution, and antibiotics are all likely candidates. One thing is for sure, Neandertals had much healthier mouths than modern humans. They contained fewer diseasecausing microorganisms and had pearly whites analogous to the gods. Their superb oral health is likely because of their healthy diet, which lacked most of the sugar and refined carbohydrates that we now eat on a regular basis today. Even if they were grunting and hunting meat on some days, they certainly knew how to interact with their environment, pass on knowledge to their offspring, and even potentially how to interact with humans in a positive way. Despite the clubs and fur cloaks, we can imagine that they were healthier than us. Would you live like a Neandertal today, if it meant you wouldn’t have to go to the dentist? Laura Weyrich is an ARC Discovery Early Career Research Fellow at the Australian Centre for Ancient DNA, The University of Adelaide.
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The Light Bulb Moment for Brain Development GEOFFREY GOODHILL & LILACH AVITAN Some elegant experiments in zebrafish have revealed how sensory experience during infancy can have long-lasting effects on the brain. he brain develops through a combination of innate and environmental factors. The initial patterns of wiring are specified genetically, but this provides only a rough starting framework. From there, neural activity is required to refine these patterns. Using the zebrafish as a model, we have now discovered more about how this process works. Neural activity in the brain is generated in two ways. Most obviously it is caused by sensory inputs such as sights, sounds and smells. However, it can also be generated spontaneously within the brain without an external stimulus. It’s as if the brain is internally rehearsing the kind of input patterns it expects to encounter from sensory stimuli. How does this spontaneous activity change over development, and how is it affected by the sensory environment? It’s obviously hard to study this in humans, but zebrafish offer an attractive alternative. Unlike humans, zebrafish grow very quickly. Within only 5 days of the egg being fertilised, when they are only a few millimetres long, they are mature enough to begin hunting fast-swimming paramecia. Larval zebrafish are also transparent, and their neurons can be genetically labelled with a fluorescent calcium indicator. When a neuron fires, calcium flows into it so that labelled neurons glow brighter when they are active. We can therefore study brain activity in the zebrafish by simply embedding the
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fish in agarose under a microscope and watching the neurons glowing. This makes it possible to observe hundreds or even thousands of neurons simultaneously. Our focus has been on a brain region called the optic tectum. This is the main part of the zebrafish brain that processes visual information coming from the eyes. While the tectum is active in response to visual stimulation, during the early life of the zebrafish it also displays large amounts of spontaneous activity. We examined this spontaneous activity every day from 4–9 days post-fertilisation (dpf). Our first finding was that the amount of activity changed with age. From 4– 5 dpf, spontaneous activity increased in frequency. However, it then declined, until by 8 dpf the frequency was back to 4 dpf levels. When recording from hundreds of neurons simultaneously, there is much more to be discovered about their activity patterns than just frequency. We therefore looked at the activity correlations between neurons, and this told us which pairs of neurons tended to fire together. This allowed us to extract the “functional connectivity” of the tectum (i.e. which neurons might be connected) based on the fact they had correlated patterns of activity. Just like the frequency of activity, we found that this functional connectivity peaked at 5 dpf and then declined again. However, we also noticed that large groups of neurons tended to fire together as “neural assemblies”. To determine which
A zebrafish head viewed from front-on (main picture) and from above (inset) showing neurons in a slice of its brain labelled with a fluorescent calcium indicator.
neurons were in which groups, we turned to “community detection” algorithms recently proposed in an area of mathematics called graph theory. Inspired in part by the huge amounts of data now available about online social networks, these algorithms determine the form of “communities” in such networks. Treating neural firing just like a social network, we used these algorithms to discover that the number of communities, and the number of neurons within each community, also peaked at around 5 dpf. It thus appears that 5 dpf is a particularly important moment in the development of the zebrafish’s optic tectum. This is exactly when they start to hunt for food.
Sensitivity to Visual Stimulation Is the development of this spontaneous activity purely driven by an intrinsic genetic program, or does it also depend on the visual stimulation the zebrafish receives early in life? To answer this question we performed two different kinds of manipulation of the visual input. First, we raised one group of fish until 6 dpf in the dark.
Second, we raised another group of fish until 6 dpf on a normal light-dark cycle but in a “featureless” environment where they saw no visual contours, just diffuse light. We then imaged spontaneous activity in the tectum as before. Both manipulations caused changes to the structure of spontaneous activity. Darkrearing caused a loss of functional connectivity and fewer neural assemblies. In contrast, functional connectivity increased after featureless rearing (i.e. it did not refine, as occurs in normally reared fish). Thus normal visual inputs are essential for the appropriate refinement of activity patterns in the optic tectum.
Behavioural Consequences While we showed that dark-rearing during early life changed subsequent brain activity, a key question remaining was whether this also had an effect on the behaviour of the fish. We investigated this using a very simple assay for the ability of the fish to hunt paramecia. This is a challenging task, since paramecia are single-cell creatures that
move quite quickly. We know from previous work that zebrafish catch paramecia primarily through their visual sense. At 6 dpf each fish was placed in a dish in the light with 50 paramecia – the first time they had seen paramecia or tried to catch their own food. After 2 hours we counted how many paramecia remained, telling us how many had been eaten. Fish that had received normal visual inputs before 6 dpf ate about half of the paramecia. However, fish reared in the dark until that point ate hardly any, even though they were hunting under exactly the same conditions as the normal fish. Remarkably, this deficit persisted to 9 dpf even though both sets of fish received the same normal visual input from 6–9 dpf. Thus, dark-rearing causes a profound and long-lasting change in the ability of the fish to catch prey using visual cues.
Critical Periods A large body of previous research has shown that the mammalian brain exhibits critical periods in its development. These are rela-
tively brief moments when particular parts of the brain are unusually sensitive to the inputs they receive. Unless it gets the right inputs at those times it will not wire up properly, even if the input is later corrected. A seminal example is the 1960s discovery that briefly blocking input to a cat’s eye during the critical period causes a permanent vision deficit in that eye, while blocking visual input after the critical period has no long-term effect. These findings in cats changed the way that children with vision problems early in life are treated by doctors. It was previously thought that the zebrafish brain developed according to a more rigid genetic program. However, our work shows that, like mammals, their brains are also sensitive to environmental inputs early in life. The relative ease with which neural activity can be imaged in the young zebrafish brain thus provides an exciting opportunity to study brain plasticity in more detail than is possible with cats or humans.
The Future There are many questions we would now like to address. For instance, is the plasticity we have observed really a “critical period” phenomenon and, if so, how long does this critical period last? Are the changes in brain wiring observed with altered input reversible? If so, what are the most effective kinds of visual input to achieve this? An essential part of our approach to this work has been the application of advanced mathematical and statistical methods to extract the maximum amount of information from our data. Indeed, several people in the team originally came from backgrounds in mathematics, physics or computer science. We believe this kind of interdisciplinary approach will be increasingly important for unravelling the highly complex rules governing brain development and function. Geoffrey Goodhill is Professor of Neuroscience and Mathematics at The University of Queensland. Lilach Avitan is a Research Fellow at the Queensland Brain Institut, The University of Queensland.
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Brain Training: Show Me the Evidence! TEJAL M. SHAH & RALPH N. MARTINS Many computer-based brain-training programs promise to improve cognitive capacity and delay age-related issues such as Alzheimer’s disease, but how credible is the evidence behind these claims? espite greater efforts to maintain brain function well into late life, the challenge of helping older adults to maintain or improve memory, judgement, learning, executive functions and processing speed remains a challenge. The high prevalence of age-related degenerative diseases such as Alzheimer’s disease makes the need to resolve this challenge more pressing. A 5-year delay in the onset of Alzheimer’s disease can save Australia $13.5 billion by 2020 and $67.5 billion by 2040. As drug trials have been ineffective to date, attention has been directed towards lifestyle strategies and interventions that prevent or delay the onset of neurodegenerative diseases. Among these approaches is evidence-based research into the use of computerised brain-training software, which has spawned a multi-billion dollar computer-based brain health and fitness industry that claims it can promote and maintain healthy brain ageing. However, most of the software programs often lack the supportive data required to validate their efficacy. We have therefore conducted a review to help give clinicians guidance when advising their patients and to help consumers decide which programs are strongly evidence based and therefore more likely to be beneficial for healthy brain ageing. We scrutinised 26 peer-reviewed studies that examined the effectiveness of seven computerised brain-training programs for healthy older adults aged over 50. We found that at least some of the commercially available brain-training programs can promote healthy brain ageing.
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Grading Brain-Training Programs We looked at the scientific evidence behind these exercises and the purpose for which they are recommended (e.g. to promote healthy brain ageing, or for dementia or other neurological diseases) and the principle behind the design of such exercises. We focused our investigation on studies directed at healthy brain ageing. We identified 18 computerised brain-training 20 |
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programs that claimed to have scientifically proven benefits. We found that 11 of the programs had no clinical trials or empirical evidence, demonstrating that their claims of effectiveness were not scientifically proven. The products of the remaining seven companies were then classified into three categories based on the strength of the evidence of their effectiveness. We assessed both the quantity and quality of clinical studies. Trials were regarded as “well designed” if they were randomised clinical trials with a control group. They were classified as being of high, moderate or poor quality as rated from one to ten on a check list. Trials with a score greater than six are deemed high quality; trials with scores between five and six were rated as moderate quality; and those with a score less than five were considered as poor quality. • Level 1 programs had at least two well-designed randomised controlled trials, one of which had to be of high quality. The brain-training programs BrainHQ and Cognifit met the criteria for Level 1. • Level 2 programs had only one high-quality randomised controlled trial. Cogmed, BrainAge 2 and My Brain Trainer were classified in Level 2. • Level 3 had only one moderate/poorly designed randomised controlled trial. Dakim and Lumosity were in Level 3. Programs that were rated as Level 1 (BrainHQ and Cognifit) mainly involved exercises that were auditory and/or visually stimulating and were used in the clinical trials. For example, in one of the auditory stimulation exercises, the user is required to listen to a sound frequency sweep that begins low and rises upward or begins high and then descends, and then determine whether they go up or down. Another exercise required users to identify a synthetically generated syllable (e.g. “ba”) from a confusable pair (e.g. “ba” vs “da”), whereas some other exercise involved identifying details in a verbally presented story.
We found that 11 of the programs had no clinical trials or empirical evidence, demonstrating that their claims of effectiveness were not scientifically proven.
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Other sets of exercises involve visual engagement. For instance, during a road tour exercise, the user stops to see roadside attractions. However, to reach them the user must spot cars in the centre of their vision while also identifying road signs on the edges of the screen. Overall, the difficulty level increases if the user performs the exercises correctly, but the difficulty level is decreased if the user performs the exercises incorrectly. In one of the Cognifit exercises named Morning Time, windows are arranged randomly on a screen and are opened momentarily, one after the other. The task is to follow the exact sequence in which the windows were opened. The task evolves as the user remembers longer sets. This task is designed to train memory. Thus, in order for the brain to be exercised effectively, the activities are required to be novel, well-tailored to the individual, and continuously challenging. Programs that currently lack supportive evidence may also be effective, given that they are mostly based on the same neuroplasticity principle. However, they could target specific cognitive domains, and thus need to be empirically validated in independent clinical studies.
Features of Effective Brain-Training Programs Brain-training programs feature different exercises that target specific cognitive domains such as memory, reasoning, processing speed and executive functions. Many effective exercises are designed according to the principle of the brain’s capability to rewire and reconnect – the neuroplasticity principle. An exercise must be adaptive according to a person’s capability, continuously challenging and audio and/or visually interactive. Some features to look for in deciding whether a program is right for you include whether the program:
• is recommended for your specific purpose, such as healthy brain ageing, rehabilitation, learning and concentration; • is scientifically validated for your specific purpose • is adaptive and engaging; • is continuously challenging; • features audio and/or is visually interactive; and • provides feedback about your progress. Programs that train the brain to be more responsive using specific tasks and increasing levels of difficulties are thought to help rewire neural pathways according to the neuroplasticity principle.
Brain Training Benefits There is now sufficient evidence to support the notion that the human brain is plastic in later life and can benefit from properly designed brain-training programs. It’s possible computerised exercises that are adaptable and continuously challenging may help the brain to rewire lost connections that are linked with dementia later in life. However, whether computerised braintraining programs can help prevent dementia onset remains to be determined. Thus, longitudinal prevention clinical trials are needed to address this important question. Evidence concerning how or where these software programs affect plasticity in brain cells or connections within the brain is lacking. Assessments using specific biological markers of Alzheimer’s disease (or other neurodegenerative diseases) such as blood markers and brain imaging would considerably enhance clinical validation of brain-training programs and assist in addressing whether these programs actually promote neuroplasticity. This would also enable greater understanding of the connection between computerised brain exercises and human cognition, and provide an insight into new therapeutic pathways. Regardless of whether new neural pathways are established, some mental exercises may work simply by increasing blood circulation in the brain, similar to physical exercise. Thus, healthy brain ageing may be achieved by maintaining or improving cognitive functions via avenues such as brain training. However, for optimal brain health a holistic approach incorporating lifestyle strategies needs to be undertaken which include social interaction, exercise, diet and sleep. Tejal M. Shah is a Research Fellow at Macquarie University. Ralph N. Martins is Director of the Centre of Excellence for Alzheimer's Disease Research and Care at Edith Cowan University, and Professor of Neurobiology at Macquarie University.
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Nick Birks, Wildflight Australia Photography
Along Came a Spider
BY SOPHIE HARRISON
Genetic studies reveal that trapdoor spiders colonised Kangaroo Island after surviving a remarkable rafting journey from South Africa. piders are not normally associated with oceanic voyages. Indeed, for much of the Southern Hemisphere’s flora and fauna – including that of Australia – it seems more likely that the current distributions of many species are a result of their presence on the ancient supercontinent Gondwana rather than by any remarkable feats of dispersal. When Gondwana broke into the land masses that are now known as Antarctica, South America, Africa, Madagascar, India and Australia, species that were already living on the supercontinent were taken with it – physically “inherited” at the point of separation. Therefore, when we see related groups of organisms with poor dispersal ability living on these land masses, we assume
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in the first instance that their distributions are related to shifting continents rather than shifting organisms. Such distribution patterns are called “vicariant”. However, advances in genetic techniques mean we can now investigate the evolutionary relationship between species and the timing of their separation, and make more robust inferences about their evolutionary history. In essence, we can use genetic similarity to calculate how closely related species and populations are to each other. As DNA usually mutates at fairly constant rates, these rates can be used to calculate when two taxa may have diverged, and therefore determine if this timing matches with historical events, such as the breakup of a land mass, the creation of a mountain range, or the formation of a river.
The Migidae are a family of trapdoor spiders that are often called tree trapdoor spiders even though many species within this family build burrows on the ground. Trapdoor spiders belong to the infraorder Mygalomorphae, which differ from other spiders by having parallel fangs and four book lungs. While most spiders usually have annual or biannual life cycles, trapdoor spiders are very long-lived, with life cycles in excess of 10 years having been recorded. Instead of using silk to create webs to catch prey, they use it to line burrows in the ground, which they use for shelter and as a base for prey capture. As a rule, they also have very limited powers of dispersal; once they have hatched and emerged from the maternal burrow, they usually disperse only a few metres, dig a burrow of their own, or find a pre-existing niche to form the basis of their burrow. They will then stay in this burrow for the duration of their lifespan, widening and lengthening it as they grow. This sedentary lifestyle has led to the logical assumption that the presence of Migidae in both Africa and Australia is due to vicariance; that is, that ancestral populations were widespread across Gondwana and travelled on the land masses that then formed Africa and Australia. But is the story more complex than this? We closely examined the evolutionary relationships among migid trapdoor spiders, including those species found in southwestern Western Australia, Kangaroo Island, South Australia, and those found in South Africa. Surprisingly, our multi-gene evolutionary tree showed that the species from Kangaroo Island (Moggridgea rainbowi) is much more closely related to those from South Africa than to its Western Australian counterparts. To further examine this relationship, we compared individuals belonging to the genus Moggridgea from Kangaroo Island and South Africa. We conducted rigorous morphological and genetic analyses to examine how close this relationship was, and discovered that M. rainbowi was not only very closely related genetically to African species but also extremely similar in appearance. The degree of genetic and physical similarity was so great that we even wondered if it was possible that the Kangaroo Island species had been inadvertently introduced by sealers who first colonised Kangaroo Island in the 1800s! However, when we employed molecular dating techniques to estimate how long ago the Kangaroo Island species and African species had split, we found that this hypothesis was not supported by our results. Astonishingly, the African and Kangaroo Island species diverged 2–16 million years ago, much (much) later than the separation of Africa from the rest of Gondwana (~95 mya), and obviously much earlier than human arrival on Kangaroo Island. Even when error margins around the estimated divergence date were doubled or even tripled, the timing of the divergence still did not match up with the breakup of Gondwana. Further-
The results of our study left only one likely hypothesis: ... that Moggridgea survived a remarkable journey across more than 10,000 km of open ocean from South Africa to Kangaroo Island. more, disparate populations of Moggridgea on Kangaroo Island itself showed genetic differentiation that was consistent with their presence on the island for several million years. The results of our study left only one likely hypothesis, and it is perhaps the most astonishing of all: that Moggridgea survived a remarkable journey across more than 10,000 km of open ocean from South Africa to Kangaroo Island. Given trapdoor spiders’ inherent lack of dispersal abilities, the most logical way that they could have survived such a longdistance journey is via oceanic rafting. This is the term given to a large mass of earth, vegetation and debris that is washed out to sea during major flood events. Rafting is already thought to have facilitated trans-oceanic voyages in many groups of organisms, including geckos and some primates. However, this is the first long distance dispersal event to be recorded in a mygalomorph spider. While this was clearly an exceptional feat, several precedents by mygalomorph spiders at smaller scales already exist, supporting the idea that they are indeed capable of dispersal across bodies of water. Indeed, mygalomorph spiders occur on the Galapagos Islands, Hawaii and the Comoros. These islands are all volcanic in origin, which means they have never been connected to continental landmasses; in all such cases, vicariance can be ruled out. It is also worth noting that trapdoor spiders may be better equipped for oceanic travel than they initially seem, particularly in terms of dispersal via rafting. Moggridgea live in secure, silk-lined underground burrows that would provide a waterproof shelter and climate control. They also construct tightly fitting trapdoors that can be sealed shut with silk, further protecting them from the elements. They have a low metabolic rate and the ability to go for months without food, and dispersal of gravid females would lead to the arrival of numerous spiderlings in any new environment. Finally, they are also somewhat resistant to drowning due to their ability to use stored oxygen, which is a critical survival tactic when their burrows are temporarily flooded during storm events. With their minimal sustenance requirements, sealable burrows and ability to “hold their breath”, these spiders may actually be the ideal passengers for oceanic rafting. Sophie Harrison completed this research as a PhD candidate at the Australian Centre for Evolutionary Biology and Biodiversity, The University of Adelaide. It has been published in PLoS ONE (http://tinyurl.com/ycexqpao).
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Figure 1. The relatively small size of the trees in the Top End’s savanna environments may not have been able to support termite colonies, leading them to evolve mounds whose size was not restricted by tree diameter. Credit: Jan Sobotnik
Cathedrals in the Desert NATHAN LO Termite mounds populate the northern Australian landscape like miniature skyscrapers, yet genetic analyses reveal that the first termites that rafted to our shores originally built their nests in trees. Why did they do this? n the opening scenes of Stanley Kubrick’s 2001: A Space Odyssey, a 3-metre high monolith mysteriously appears outside a cave, and causes much bewilderment among its proto-human observers. If we fast-forward three million years, the towering termite mounds of northern Australia inspire similar curiosity among those who behold them. Where did they come from? How long have they been here? Why are some much taller than others? How did they evolve? To answer these questions, we are carrying out DNA-based studies on Australian termites and their overseas relatives. Australia has one of the most diverse range of termite mounds of any continent, and also boasts the tallest mounds on
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Earth. Known as cathedral mounds, these structures reach up to around 6 metres in height and 2 metres in diameter, and are built by millions of blind, grass-feeding termites (Nasutitermes triodiae). There are no architects, no engineers, no plans, no foremen. The instructions for building the mound are literally in the DNA of the colony’s members. Given a worker N. triodiae stands 3 mm in height, these structures are the human equivalent of more than four Burj Khalifa-sized skyscrapers stacked on top of each other, and can survive for more than 80 years. Termites and their nests play a key role in northern Australia’s ecosystems, and have earned termites the title of “ecosystem engineers” and “keystone species”. Whereas savanna habitats in
We also used what is known as a “molecular clock” to estiother parts of the world have large mammals to process most biomass, termites fulfil this role in northern Australia. In these mate when various branches appeared in the trees over the past habitats, termite biomass can reach as high as 20 g/m2, making few million years. To do this we used termite fossils of known them the dominant animal group. Their subterranean tunnelling age, and calculated how fast termite DNA changes. Rates creates soil structure, enhancing aeration, water infiltration are typically quite slow – in the order of about three changes and root penetration. Assimilation of nitrogen from the air per 100 DNA nucleotides (C, G, A, T) per million years. We into protein by the symbiotic bacteria in their guts improves soil were particularly interested to know if termite mounds have fertility. Termites also act as a year-round food source for many dominated our landscapes prior to Australia’s split from other other species, from invertebrates to vertebrates. Without them, parts of Gondwana around 55 million years ago, or if they the northern Australian landscape and its biodiversity would evolved more recently. look vastly different. Termite nests are central to their biology. The queen and king usually mate for life, and must be protected from the outside world. Their offspring, thousands of which can be produced each day in some species, must be fed and raised by their sibling workers. Most offspring will become workers and soldiers but, once a colony is established, a select group each year is raised as winged reproductives. These will fly out of the nest during summertime and attempt to start a new colony of their own with a prince or princess from another nest. The function of termite mounds thereFigure 2. Nasute termites have colonised Australia on three separate occasions between 10 and 20 million years ago. Credit: Toru Miura fore includes protection from invertebrate and vertebrate predators, storage of food, We looked at two particular groups of termites. The first is and maintenance of a relatively constant internal environment that is conducive to colony growth, also known as “home- the genus Coptotermes, which contains Australia’s main pest ostasis”. The latter aspect has been relatively well-studied in species C. acinaciformis, as well as the northern hemisphere Australian magnetic termite mounds, whose north–south orien- pest C. formosanus, on which billions of dollars each year are tation is believed to provide favourable temperatures in different spent on damage and control. We showed that, like many other areas of the mound throughout the day. Many termite mounds, Australian animals, including goannas, Coptotermes colonised including those in southern Australia, have internal tempera- Australia from Asia around 12 million years ago. This tures in the high twenties, even when ambient temperature is followed the collision of the continental plates upon which Australia and South-East Asian countries lie. well below that. Like their Asian ancestors, Coptotermes continued to build Although the function of mounds has been studied in some detail, the evolutionary origins of termite mounds have, until their nests inside living trees once they arrived in Australia. recently, received very little attention. To understand how However, they transitioned to mound-building multiple times these mysterious structures evolved, and how long they have independently. Although Coptotermes species are also found been in Australia, we constructed family trees of different in South Africa, South America and Asia, they build mounds termite species, some of which build mounds and others that only in Australia. Coptotermes mounds are made with a similar domed strucform different kinds of nests. These include nests inside rotten wood, underground in the soil, inside living trees or on the ture and are usually 1–2 metres in height. The outside of the mound consists of a hard clay outer wall that can be up to outside of trees, sometimes up to 10 metres in the air. To work out these family trees, we sequenced the same DNA 30 cm thick. Under this, the mound is filled with thick “carton” region in each species, and compared the sequences with each made from partially digested wood and faecal matter. This other. Once we had the trees we could infer how nest types carton layer looks a little like the human brain due to its high level of reticulation. have changed throughout the evolution of the group. NOV/DEC 2017 |
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Figure 3. Phylogenetic analysis revealed that the first nasute termites to colonise Australia constructed nests on tree branches. Adapted from Arab et al. (2017) Biology Letters 13, 20160665
Under the carton, often at around ground level but sometimes lower, is the nest itself. In some species this is the size and shape of a basketball, and consists of a vast network of chambers, tunnels and galleries made of very thin carton material that is like brittle paper. One case of mound evolution involves C. acinaciformis, which is a living-tree nester in the south-east of its distribution and a mound-builder in northern Australia. We think that the relatively small size of the trees in the Top End’s savanna environments may not have been able to support C. acinaciformis colonies, leading them to evolve mounds whose size was not restricted by tree diameter. Building a nest in a mound compared with inside a tree has additional potential advantages, including a greater ability to regulate gas exchange in order to maintain homeostasis. This is because a mound is more exposed to air movement through its outer layer than a nest inside a tree, and can therefore take advantage of evaporative cooling. It’s unfortunate that southern C. acinaciformis did not evolve mound-building too, because it would make their detection and eradication much easier when they attack human structures. The second group of termites we studied were nasute termites, which include the cathedral mound-builders 26 |
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N. triodiae (Fig. 1). Nasute termites get their name from the snouts on their soldiers, which spray chemicals at their enemies or competitors (Fig. 2). We compared the DNA of 42 Australian nasute species with dozens more species from overseas, and found that this kind of termite has colonised Australia on three separate occasions between 10 and 20 million years ago. For one of these colonisation events we can infer that the last common ancestor of the Australian species constructed arboreal nests on tree branches (Fig. 3) because all of their overseas relatives have this characteristic. These arboreal nesters are often found in coastal areas, including in Central America and Asia. To get to Australia, their nests may have been swept into the ocean during storm or tsunami events, and have made it to Australian shores due to favourable currents. Once in Australia, these termites continued to form nests in trees, and indeed two species along the eastern coast of Australia still do this. The arboreal nests of one species, Nasutitermes walkeri, can be easily seen when walking along Sydney’s foreshore. During the period in which nasute termites arrived in Australia, the rainforests that once covered the continent were receding, and dry woodland, scrubland and desert habitats began to take over. In response, the arboreal nasutes that had established themselves in Australia evolved the ability to form their nests on the ground rather than in trees. Drier conditions may have made arboreal nest-building impractical, perhaps due to an inability to maintain the right levels of humidity or temperature in nests up in the trees. The formation of mounds may have allowed better regulation of these environmental variables. Our analyses indicate that the transition from building nests in the trees to building them on the ground happened on multiple occasions (Fig. 3). In some cases the transition was to underground nesting rather than mound-building. The evolutionary pathway followed by these termites therefore follows that of humans in some respects. On the basis of fossil bone analysis, ancestral proto-humans that lived six million years ago in Africa are believed to have been tree-dwelling. As was the case for tree-dwelling proto-humans, the descendants of arboreal nesting termites would go on to create large metropolises featuring millions of individuals, with a relative size larger than any structure on Earth. Our work shows that termite mounds have been a part of our landscape for the past 15 million years or so, and are the result of ancient colonisation from other areas of the world, particularly Asia. We have shown that ancient Australian termites were able to adapt and survive in the face of significant environmental change, which has enabled them to become one of the dominant animals in the north of the country. Nathan Lo is an Australian Research Council Future Fellow in the School of Life and Environmental Sciences at The University of Sydney.
bunhill/iStockphoto
The Global Collapse of the Oncology Market MARTIN ASHDOWN A new approach to cancer treatment promises the use of fewer drugs and shorter treatment periods, leading to a “big short” of stocks that profit from oncology. he cancer industry is literally a “growth” industry worth hundreds of billions of dollars per annum. A lot of people make a living out of cancer, and each year the market expands: global estimates predict 6.5 million cancer fatalities this year. While the industry’s outdated practices haven’t significantly improved outcomes for patients in decades, they are now being replaced by a new paradigm of immune-based cancer therapy. This new therapeutic approach “tweaks” the individual patient’s immune system to destroy the cancer – and it works. This seismic shift portends the overthrow of a traditional business model’s value chain, with potentially broad economic consequences. If cancer becomes curable, the cancer sector’s valuation would collapse along with careers, companies and downstream effects to other sectors. Fanciful a few years ago, this scenario is now being played out with significant aspects of the cancer industry now under assault. In 2014 global pharmaceutical giant GlaxoSmithKline offloaded a significant portion of its cancer drug portfolio to another corporate giant, Novartis, for US$16 billion. Other major corporate players are now moving into the new era of cancer immunotherapy, buying companies at inflated prices. For instance, Gilead recently purchased Kite Pharmaceuticals for US$12 billion. More recently, Australian biotech company Bionomics announced its exit from cancer drug development. These are all signs of a strategy to dispose irrelevant assets of ques-
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tionable value while clambering for a stake in the next big thing. Investment momentum in companies drives their share prices higher due to the prospect of new products, considerable future earnings and a dominant market position. Any hint of a threat to the status quo will attract the attention of savvy market operatives who could “short” the share price of exposed companies, thus snowballing a collapse.
A New Approach In 2008 the US President’s Cancer Panel made several stark admissions. “The toll of cancer has become simply an awful part of life... incidence is rising for several cancers… the most intransigent of malignancies remain impervious to treatment... and both proven cancer prevention and absolute cure remain elusive”. The report went on to say:
Despite (President Nixon) declaring a national war on cancer in 1971 and investing many billions of dollars since then to understand and defeat cancer, our success against the disease in its many forms has been uneven and unacceptably slow. The reduction in suffering by patients and their families would be incalculable. The benefit to our nation in lower health care costs and heightened productivity would be an untold bounty to our economy.
These comments had been preceded in 2006 by US health economists Kevin Murphy and Robert Topel, who made the following modelling observation in the Journal of Political Economy: “A permanent 1 percent reduction in mortality from NOV/DEC 2017 |
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cancer has a present value to current and future generations of Americans of nearly $500 billion, whereas a cure (if one is feasible) would be worth about $50 trillion”. Recent advances in cancer immunotherapy have revealed a profound flaw in our previous understanding of how to successfully treat cancer. Rather than focusing attempts on directly treating the cancer with extended periods of chemotherapy or
Trial data are showing that shorter courses of chemotherapy or radiotherapy give similar results to longer standard treatment protocols. radiotherapy, this new era of immuno-oncology is attempting to leverage the patient’s own immune system by targeting and disturbing the control mechanisms that the immune system normally uses to quell inflammation. These insights have shown that limited treatment can achieve complete responses where all cancer disappears, obviating the need for extended periods of treatments and their associated costs, not only for the patient but also under-resourced healthcare systems. Data emerging from recent cancer immunotherapy trials potentially explain the decades of failure in treating this disease effectively. In simple terms, we may have been looking in the 28 |
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wrong place by being too cancer-centric in our approach to treatment. This misunderstanding has led R&D down blind alleys and made the effective treatment of late-stage patients elusive, time-consuming and expensive. Such trial reports are also bringing into question the random and toxic “carpet bombing” of patients and their immune systems with chemotherapy and radiotherapy, which appear to have been indiscriminately destroying the very thing we are now attempting to preserve and accurately manipulate.
Promising Results The longstanding cancer-centric therapeutic business model places the patient on an expensive and toxic “merry-go round” where companies, medical specialists and others using costly diagnostic and therapeutic equipment and drugs “clip the ticket” on each revolution as the patient is managed into the ground over a 5–10-year period. However, this global business model’s value chain is now under assault. The newly gained insights into the fundamental nature of cancer immunology may rapidly lead to the use of fewer drugs and resources over shorter treatment and post-treatment periods. New immunotherapeutic drugs can have spectacular clinical effects and deliver complete responses in a minority of advanced cancer patients for whom other previous attempts have failed. The mode of action of these drugs is clearly telling us that when these drugs work, Tawesit/Adobe they are manipulating a pre-existing cancer immune response, and not establishing a new response. This tells us that the immune system is not ignorant of the presence of the cancer; rather, the immune system appears to be attenuating itself through its normal control mechanisms. These new drugs are guiding us towards the use of our limited resources more effectively, with potentially massive cost savings. The obvious consequence of this profit reduction to the corporate sector, and reduced distributions to shareholders, will be stockmarket downgrades. Structural cracks are already appearing in the oncology edifice. Trial data are showing that shorter courses of chemotherapy or radiotherapy give similar results to longer standard treatment protocols. Obviously, this reduces the debilitating toxic side-effects of therapy, as well as the expense of treatment. Furthermore, trials have shown that patients who were thought to be refractory to a drug can later respond when retreated.
Further research has discovered off-target effects of radiation healthcare stocks. These market operatives could then shorttreatment, with distant untreated tumours remarkably disap- sell these exposed stocks, with obvious consequences – a broader pearing in addition to the therapy-targeted lesions. This is most market sector collapse. There may also be some significant downstream economic effects into the health insurance and likely immune-mediated. Similarly, a compound known as PV-10 can cause complete general insurance sectors, with possible changes to actuarial responses when injected into malignant melanoma lesions. life tables as more patients live longer with and without disease, Remarkably, nearby uninjected lesions can also regress via or are cured entirely. immune-based destruction, not unlike a vaccination event. PV-10 is actually the cheap food and fabric dye Rose Bengal made up as a 10% water solution. This dye seems to work just as well as more expensive and more complicated agents such as oncolytic viruses. Further, the recent clinical success of immune “checkpoint inhibitors” (which take the brakes off the immune system) has created renewed interest in the mode of action of an older (offpatent) immunotherapeutic drug, interleukin-2. This drug, first introduced in the early 1990s, is still used to treat two very different advanced cancers: melanoma and kidney cancer. Approximately 5–10% of these patients consistently experi- Immunotherapy leverages the patient’s immune system by targeting and disturbing the control mechanisms that the immune system normally uses to quell inflammation. Credit: royaltystockphoto/Adobe ence complete responses and As these developments unfold we’ll see an increasing number can survive long-term. This shift in scientific and clinical thinking towards cancer of immunotherapy trials and regulatory approvals, more patients immunotherapy, together with the general public’s awareness responding to treatment or retreatment with a variety of agents, of reports of high profile cancer patients attaining these remark- more articles discussing the off-target effects of radiotherapy, able responses (some with limited treatment), is changing our more trials using interleukin-2, and shorter courses of chemoexpectations of a cure. It’s predicted that this transition, while therapy and radiotherapy performing at least as well as current expensive now, will rapidly lead to dramatic cost reductions lengthy regimens. Of great interest is the evolving story of how for primary cancer drugs, surgical procedures and secondary a cheap food and fabric dye, Rose Bengal/PV-10, can cause maintenance drugs used to manage treatment-related co- complete remissions. morbidities, infections, nausea and pain. A cure for cancer would be an economic disaster for the global healthcare market and a boon for government healthcare budgets. This is palpable and imminently on the horizon as, The Next Big Short? With the prospect that more patients being successfully treated after decades of research activity without insight, oncology has or living longer will lead to falling revenues and 5-year sales finally focused on the best rational drug design factory – the projections across the sector, informed market analysts could immune system. downgrade longstanding pharmaceutical, biotechnology and Martin Ashdown is a Research Fellow in The University of Melbourne’s Faculty of Medicine. NOV/DEC 2017 |
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The Art of Science The Walter and Eliza Hall Institute has created an exhibition of gorgeous images revealing biological processes such as a mammary gland during lactation, deadly parasites that resemble neon flowers, and what happens when you grow a lung in a laboratory.
EYE OF THE BEHOLDER The green and magenta “tendrils” above show the network of blood vessels that are essential for the eye to form. This network must eventually be removed for the eye to function normally. The cells making up these blood vessels will undergo a type of controlled death caused by the green macrophages suspended among the vessels. These scavenger cells not only promote the death of the blood vessels, but also eat the remains. Studying the controlled death and removal of cellular debris from the eye enables Leigh Coultas and Stephen Mieruszynski to better understand how blood vessels live and die, and inform new treatments for disease.
PROTEIN CAVES Protein caves (above) is a snapshot from a 3D structure of a protein called DCLK1, which plays a role in promoting certain cancers. One of these is gastric cancer – the fourth most common cause of death from cancer worldwide. The bright multi-coloured “hills” reveal the protein’s uneven surface, and the dark patches in between are its “caves”. The caves are an important feature because blocking access to these areas – which are used as binding sites to other molecules – could enable the creation of drugs that disable DCLK1. Researchers at the Hall Institute are working to design a drug that will fit perfectly into one such cave, and eventually stop cancer in its tracks. Credit: Isabelle Lucet and Onisha Patel
Credit: Stephen Mieruszynski and Leigh Coultas
PARASITE BOUQUET Toxoplasma gondii is a common parasite that infects 30–80% of people worldwide. It can be particularly dangerous during pregnancy and for people with weakened immune systems. The parasite is tiny, and hundreds can fill a human cell. As the Toxoplasma parasite grows inside a cell, it forms beautiful patterns that look like flowers, called rosettes. In this image, you can see that some of the rosettes look like daisies or sunflowers, while others look more like tulips and lilies. Simona Seizova is testing new techniques to disable Toxoplasma parasites. These images help her to test how effective the techniques are at killing the parasite as part of the quest to find new treatments for the disease. Credit: Simona Seizova
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Credit: Casey Ah-Cann
MILKY WAY This cluster of intricately decorated spheres (left) is actually a magnified snapshot of a mammary gland during lactation. Breast tissue contains thousands of these little spheres, which work in unison to produce milk. The yellow patterns painted across their surface are tiny muscles that contract and release, helping to squeeze milk out into the mammary ducts. Look closer and you’ll see purple flecks nestled in and around the structures. These are immune cells on high alert for any threats in order to help keep the breast tissue healthy. Seeing the mammary gland in such exquisite detail gives researchers a better understanding of how these structures form and how breast tissue works together with the immune system in surprising ways to enable milk production. Credit: Julie Sheridan and Edwin Hawkins
ROOTS This image shows a lung in its very early stages of development. As it grows, the neon-coloured “roots” will eventually thin and multiply into the intricate airway structures that form an adult lung. Casey Ah-Cann is growing this lung in the laboratory to investigate which genes impact healthy development. She does this by blocking the function of particular genes and observing how the organ is affected.
A SPECK-TACULAR WAY TO DIE Armies of cells that make up the body’s immune system help to protect it from infection. The bright green masses in the image on the left are immune cells called macrophages, which form the body’s first line of defence. Macrophages can detect bacteria and viruses, and warn other cells of potential threats. In some cases, like in this image, they consume the threat and self-destruct. The lone blue ring to the right of this image is a cell nucleus, and is all that remains after a macrophage has “taken one for the team”. The adjacent red dot is called an ASC speck, which indicates that the macrophage called for back-up in its final moments. Understanding how cells protect the body helps researchers to design better treatments for patients with disorders of the immune system, such as arthritis. Credit: Dom De Nardo
BRAINBOW The higher cortex is responsible for complex brain functions, such as critical thinking and problem-solving. The colours of the “Brainbow” in this image each represent a different layer of the higher cortex of the brain during development. The primary colours have been selected specifically to avoid confusion when colours overlap. Where red overlaps with blue, we can clearly see purple. By colouring and layering brain tissue, Maria Bergamasco can study the impact of disrupting or altering genes at different stages of brain development. This will help her to discover what goes wrong in cases where the higher cortex doesn’t function as it should. Understanding what goes awry in early brain development enables better diagnosis and treatment for people with intellectual disabilities. Credit: Maria Bergamasco
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The Secret Life of Dolphins HEIDI PEARSON & GABRIEL MACHOVSKY-CAPUSKA New underwater camera technology has captured the social lives of wild dolphins for the first time, revealing how deep and for how long they dive, how they nurture their young and even how they play with objects in the ocean. olphins are one of the most visible, intriguing and charismatic creatures of the sea, yet we know very little about what they’re doing underwater. Until now… Our team has developed a tracking device that has provided the first glimpses of dolphin behaviour from their perspective and on their own terms. With this information we can better understand the daily life of dolphins, such as how they interact with one another, how mothers raise their offspring, how they find food, and how they use their habitat. We can also understand how these animals might be impacted by threats such as coastal development, shipping traffic, vessel noise and interactions with fishing gear. Putting all of this together will help us to protect them.
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Studying Wild Dolphin Behaviour Dolphins are notoriously difficult to study in the wild. They have a small body size, are fast-moving and live in groups that can contain 1000 or more individuals. Traditionally, dolphins have been observed from small research vessels that travel alongside the group. However, as dolphins spend only a small fraction of their time at the surface, scientists are unable to see many behaviours and social interactions. In addition, it’s nearly impossible to follow a single individual in these large dolphin groups. Therefore, observations are often taken at the group level, which may obscure important individualistic behaviour. For the past 20 years, researchers have been attaching video cameras to large cetaceans such as humpback whales, blue whales 32 |
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and sperm whales. This has provided detailed information about the movement and behavioural patterns of these species. However, the small body size and fast nature of dolphins prevented researchers from successfully deploying miniaturised cameras on them. Our multidisciplinary team developed a special technique for attaching our cutting-edge C-VISS (Cetacean-borne Video camera and Integrated Sensor System) device to dolphins.
A New Dolphin-Tracking Device Our video camera was modelled on a system developed to record the behaviour of seabirds. However, attaching a video camera to a dolphin comes with a unique set of challenges that differ from seabirds. For example, while it’s possible to capture a masked booby to attach the camera, it’s not possible to capture a dolphin so we had to develop a specialised pole to deploy the device. While it’s possible to tape the camera to the tail feathers of a seabird, it’s not possible to do the same on dolphins so we had to develop a special attachment method using suction cups. Finally, dolphins dive deeper than boobies so we had to ensure that our system was both waterproof and strong enough to withstand the increasing pressure during deep dives. While the video camera is the central component of our device, C-VISS contains additional instruments to help us to understand dolphin behaviour. A time–depth recorder measures the diving behaviour, allowing us to understand how deep and for how long a dolphin carrying the device is diving. C-VISS also contains satellite and VHF transmitters that help us track the dolphin while it’s tagged and to recover the device once it falls off the dolphin.
C-VISS is archival, so it must be recovered to download the data. The video camera, depth logger and transmitters are held in a special float that is durable enough to withstand the pressure increases that occur while a dolphin dives, yet light enough that it is buoyant. When the suction cups detach from the dolphin, the device floats to the surface, sending a signal to a satellite with the approximate geographic coordinates. Once we arrive in the area, we use a VHF antenna to find the device. Importantly, C-VISS is non-invasive and does not harm the dolphin carrying the device. We conducted a series of trials with a Pacific white-sided dolphin at the Vancouver Aquarium and several dusky dolphins in the wild, and we did not detect any negative impacts of the device on the dolphins. One tagged dolphin appeared to be so undisturbed by C-VISS that we even observed it sleeping at the surface!
Meet the Dusky Dolphin Working with our project partners at the New Zealand Department of Conservation, Massey University and the US National Oceanic and Atmospheric Administration, we spent 2 years developing, refining and testing the device. We then tagged eight free-swimming wild dusky dolphins off the coast of Kaikoura (Fig. 1), and obtained nearly 9 hours of video footage. The longest attachment duration was 5 hours while the shortest attachment duration was 9 minutes. The attachment duration depends on a variety of factors, including where the device is placed on the body, the strength of the suction cups and the dolphin’s behaviour. Dusky dolphins are bioindicators: any changes we observe in their distribution, abundance and behaviour indicate larger changes in the ecosystem. We have been making boat-based observations of duskies since 2004, and this gives us a good understanding of their behaviour at the surface. However, we have always wondered what they were doing underwater. Kaikoura is a perfect place for studying duskies because approximately 1000 individuals occur off the coast at any given time. During the day, duskies are typically found near the coast where they socialise, rest and travel in large groups. These groups can be quite boisterous as individuals perform an amazing array of leaps including backflips, somersaults, side slaps and belly flops. During the night, duskies move away from the coast to feed on fish and squid in the waters of the Kaikoura Canyon. Once this midnight feast is over, the dolphins return to the coast in the early morning hours where they start the cycle over again. A Day in the Life of a Dusky Dolphin For the first time we are seeing the behaviour of wild dolphins from their perspective, and getting an indication of what a day NOV/DEC 2017 |
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Figure 1. The C-VISS tag is attached to a dusky dolphin with suction cups.
in the life of a dusky dolphin is like. Our video footage has even revealed instances where the dolphin was filming our research boat! What have our data revealed? For example, how social are they? How do mothers care for their calves? What is their habitat like? How deep, how often, and for how long do they dive?
We are seeing how social individual dolphins are. We can quantify this by recording the number of individuals swimming with a tagged dolphin at any given time, and by looking for signs of affection such as flipper rubbing: dolphins show friendliness by gently extending their flippers to touch another dolphin’s flipper or other part of the body.
Figure. 2. Video stills from C-VISS showing mother–calf swimming behaviour. Left: A dolphin calf swims side-by-side with its mother in the echelon position. Right: A dolphin calf swims underneath its mother in the infant position.
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We are also seeing how mothers care for their calves. A calf typically swims in one of two positions near its mother (Fig. 2). It will swim beside its mother in echelon position, which helps the calf to get a “free ride” by riding the pressure waves created by the swimming action of its mother. A calf will also swim underneath its mother in infant position. This may provide protection from predators as the calf is physically tucked under its mother. Additionally, when viewed from below, the mother–calf pair looks like one large dolphin (Fig. 3), which may be a deterrent to predators such as sharks. We are even seeing intimate behaviours such as calves nursing (drinking their mother’s milk), which for most dolphin species is virtually impossible to be seen by researchers on the surface. We are also seeing how dolphins use their habitat, from kelp forests to the sandy sea floor to depths beyond the sunlit zone where the sea becomes dark. We are also seeing how dolphins interact with their habitat, for example by playing and “wearing” kelp on their flippers (Fig. 4). Finally, we can correlate all of these behaviours with data obtained from our time–depth recorder. This helps us to determine how behaviour changes according to how deep and for how long the dolphin is diving.
Future Research Directions All that we have seen so far is revealing the complexity of the lives of dolphins, yet we are just breaking the surface with the power of this new research tool. We foresee several important future research directions. Understanding the nutrition of wild marine predators, such as dolphins, is a challenge that science has yet to solve. We need to know exactly what the food and habitat requirements of marine predators are. Learning more about their feeding patterns on a daily basis and what nutrients they contain will be immensely useful for protecting endangered species. As we continue to study duskies and other dolphin species, we can better monitor and understand changes to the marine environment. As we continue to monitor dolphins and correlate fine-scale information on their social, foraging and diving behaviours with data on how the ocean is changing with respect to sea surface temperatures, circulation patterns and plankton abundance, we will have a better understanding of how climate change is affecting other, less visible marine organisms. Last but certainly not least, seeing the world through the eyes of a dolphin will help us to better protect them. The more we understand about how individual dolphins find food, care for their young, find mates and avoid predators, the better we can conserve them by establishing protected areas and developing policies that limit human interference with these behaviours. Heidi Pearson is Associate Professor of Marine Biology at The University of Alaska Southeast. Gabriel Machovsky-Capuska is Loxton Research Fellow at The University of Sydney.
Figure 3. Video stills from C-VISS showing a dolphin calf swimming. From below, the mother–calf pair looks like one large dolphin, which could help to protect them from predators like killer whales. (Image quality is a function of video camera resolution.
Figure 4. A video still from C-VISS showing a dusky dolphin swimming through kelp and draping it over its head. This is a form of play behaviour. The dolphin’s head and C-VISS antenna are visible.
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photo5963_fotolia/Adobe
A Plasmid Goes Viral RICK CAVICCHIOLI & SUSANNE ERDMANN No one really knows how viruses evolved, but scientists looking for Antarctic viruses from extremely cold and salty lakes have discovered new clues. ntarctica is probably the Earth’s most important continent for influencing global climate and ocean ecosystem function. Winds descending off the continent cool the surrounding seawater, causing an annual formation of sea-ice stretching up to 20 million km2 (about 2½ times the area of Australia). The cooling has two effects: it causes seawater to become more dense, and salt precipitates from the sea-ice as it forms, so the sea-ice essentially becomes fresh water. As a result, a downward force is generated that drives global ocean currents. The cold Southern Ocean surrounding Antarctica also supports the growth of phototropic microbes that harvest the sun’s energy and fix CO2 from the atmosphere. These microbes, and others that recycle nutrients, represent the beginning of a marine food web that feeds krill and all other ocean life. As one of the tiniest forms of microbes, viruses play essential roles in all of the Earth’s ecosystems. Viruses may cause about 20% of the cellular microbes in oceans to lyse and die
A
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each day, causing nutrient turnover and further microbial growth (http://tinyurl.com/abmjhtf). Viruses play particularly important roles in the Antarctic because its waters harbour fewer larger predators, so viruses can contribute even more to the natural turnover in these ecosystems (http://tinyurl.com/ jvc5xl3). DNA sequencing of entire Antarctic microbial communities in a freshwater lake on the Antarctic Peninsula discovered a high level of unique viruses (http://tinyurl.com/ybw8fuc3). The 2009 report in Science noted how the viral communities were dynamic, changing in response to the state of the ice cover on Lake Limnopolar. In 2011 Cavicchioli’s laboratory at UNSW discovered a form of virus called a “virophage” at Organic Lake, a marinederived hypersaline lake near Australia’s Davis Station in Antarctica (http://tinyurl.com/y79ng77a). Virophages depend on the coinfection of their host by another virus, typically a giant virus. While virophages negatively impact these larger viruses, Cavicchioli’s lab concluded that the interactions between the
Water samples taken from Deep Lake (pictured here) found numerous viruses, while samples taken from hypersaline lakes in the Rauer Islands (below right) found DNA sequences from a plasmid that encoded virus-like particles.
Plasmids, Viruses and Promiscuity In a twist on what biology can offer up from the Antarctic, we recently led a study that discovered a plasmid masquerading as a virus (http://tinyurl.com/yalyzus3). Plasmids are small, circular, double-stranded DNA molecules found in many types of microorganisms. The findings, published in Nature Microbiology, mean there are new ways to consider how viruses have evolved. The backdrop to the discovery was a 2013 study that analysed the genetic make-up of a microbial community in Deep Lake, a marine-derived system that has a salinity about ten times that of seawater and is the coldest aquatic environment known to support life – temperatures in the lake are as low as –20°C. The Cavicchioli group reported that the lake supported a community of very promiscuous microbes that exchanged DNA with each other (http://tinyurl.com/y8cpkya3). The haloarchaea microbes require very high levels of salt to grow, and can be found in environments like the Dead Sea in Israel and Lake Tyrrell in Australia, on salty fish, and in solar salterns worldwide where they colour the ponds pink/purple. Another study of Deep Lake published in The ISME Journal by Cavicchioli’s group analysed proteins from environmental samples rather than DNA. It concluded that viruses were likely to be important in transferring DNA between the different types of haloarchaea (http://tinyurl.com/y89s7kdq).
Deep Lake
Vestfold Hills
Davis Station
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31 k m
Organic Lake virophage and the larger virus could improve the ability of their algal host to photosynthesise, and hence contribute to a better functioning ecosystem.
Sørsdal Glacier
Filla Island
Rauer Islands A Plasmid Masquerading as a Virus To advance our understanding about the haloarchaea and their viruses, Cavicchioli’s group took water samples from hypersaline lakes, including some from lakes in the Rauer Islands about 30 km away from Davis Station, and brought them back to the lab at UNSW. Erdmann isolated viruses from the water samples and sequenced their DNA so she could discover which types of viruses were present. During this phase of the research she discovered that one of the sequences was for a plasmid, not a virus. The plasmids encoded proteins that were a part of virus-like particles. Furthermore, the particles harbouring the plasmids could be used to “infect” other haloarchaea that did not already contain the plasmid.
Rauer 1 Lake One of the fundamental distinctions between plasmids and viruses is that only viruses are known to encode proteins that go into viral DNA particles, and are capable of infecting cells. Plasmids, on the other hand, do not build particles that transfer by an active infection process. Instead, they move between cells, either when cells come together and transfer plasmid DNA during cell-cell contact or when naked extracellular plasmid DNA (e.g. arising from cell lysis) is taken up into new cells. Thus the discovery blurs the boundaries between the definition of plasmids and viruses, with this new plasmid being able to infect – just like a virus. NOV/DEC 2017 |
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d
Plasmid vesicles
Plasmid vesicle
Haloarchaea host and the vesicles it produces that contain the plasmid (a–c). (d) Virus-like particles from the hypersaline lakes. Credit: Susanne Erdmann
Membrane Vesicles and Gene Exchange Erdmann showed that the particles that the plasmid was packaged in was a “membrane vesicle” – a section of the host membrane that forms a “bleb” and detaches. Many life forms produce membrane vesicles. For instance, human cells use vesicles to move lipids and other cellular components around between cellular organelles. Some human viruses, like influenza and hepatitis C, require vesicles to propagate. Some of the vesicles have surface structures composed of proteins that have similarities to some of the plasmid proteins. So what we have found is a new type of plasmid that behaves like a virus. Furthermore, the vesicles harbouring the plasmid appear to have structural features in common with vesicles in humans that play roles in both cell function and the life cycle of human viruses. These are interesting evolutionary connections. Erdmann discovered different forms of the plasmid in haloarchaea from Deep Lake and the Rauer Island lakes. She learned that the plasmid could integrate into the DNA of host cells, excise from the host carrying long stretches of host DNA, get packaged into particles and then transfer to new hosts. The discovery that the plasmid could transfer host DNA was another important finding as it demonstrated a plausible mechanism for the observed promiscuous gene exchange in Deep Lake. It will take more work to determine if the plasmid does perform this role in the lake, but there is certainly a good reason to go looking. The Evolution of Viruses Scientists studying viruses have wide-ranging opinions about how they evolved, including whether they pre-dated cells or evolved from cells. One theory, the escape hypothesis, is that viruses evolved as fragments of cellular DNA capable of infecting other cells so they could escape and propagate in a wider range of hosts. Our discovery of a virus-like plasmid fits with this theory while challenging how scientists think about the distinction between viruses and plasmids. 38 |
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... the plasmid could integrate into the DNA of host cells, excise from the host carrying long stretches of host DNA... and then transfer to new hosts. We speculate that plasmids that form plasmid vesicles may have been the predecessor of some viruses. Our reasoning is along the following lines. It is now known that plasmids can produce proteins that go into host membranes, leading to the formation of specific types of membrane vesicles that harbour the plasmid. These plasmid vesicles then leave the host and go off to infect other hosts that do not already contain the plasmid. This phenomenon is like a virus. Some viruses, called pleolipoviruses, reproduce by encapsulating themselves in vesicles made from lipids from the host membrane combined with their own proteins. Other viruses, such as head-tailed viruses, encode specific proteins that form heads, specific proteins that form tails, and other “machinery” that collectively makes these types of viruses structurally sophisticated entities. The plasmid vesicles are less defined in their structure than many types of known viruses, perhaps being most similar to pleolipoviruses. It’s therefore conceivable that some types of viruses acquired their refined traits through an evolutionary process that commenced with plasmids that form plasmid vesicles. Since ~80% of life on Earth lives at temperatures below 5°C, this research in Antarctica provides insights of global relevance. The discoveries also help to illustrate why Antarctica needs protection so that future generations can continue to learn and benefit for years to come. Rick Cavicchioli is Professor of Biotechnology and Biomolecular Sciences at UNSW Sydney, where Susanne Erdmann is a Research Associate.
CONSCIENCE
Appropriate Behaviour? Plagiarism by academic reviewers is hard to prove, and even harder to punish. Most academics will be familiar with the processes for dealing with a case of suspected plagiarism by a student. The plagiarism is typically flagged by software such as Turnitin or SafeAssign. The lecturer can then view the submission, with passages containing suspected plagiarism highlighted with links to original sources. Often the plagiarism is an innocent mistake. Blatant cheating is rare. Given this limited exposure, it comes as quite a shock when you suspect that your own work has been plagiarised by another academic. My own experience here might be informative. About 2 years ago I first submitted a paper (written with two colleagues) to a journal (Journal A), where it was rejected. The same story repeated at Journals B and C. That process took a year. As I prepared to submit to journal D, I spotted a new paper at that journal in an “early view” version that bore a striking resemblance to my own paper. The logic, style and facts all matched. It looked very much like our own work had been plagiarised, or to use the term preferred by journals: “appropriated”. The most likely source of the plagiarism: one (or more) of the authors of the new paper had reviewed an earlier version of our manuscript, and incorporated the ideas directly into their own work. I first contacted the editor of Journal D, who promised to give the matter their full attention. Two months later, the editor apologised for not having reviewed the matter as he was new to the position. In the coming months I received several similar emails from the editor, each promising attention that never materialised.
While this period of inaction persisted, I set about researching the processes for suspected plagiarism. The Committee on Publication Ethics (COPE) offers protocols that many journals follow. Those protocols did not inspire confidence. The suspected plagiarist has multiple avenues to avoid both detection and sanctioning, particularly if their university or organisation chooses to take no action. In such circumstances, COPE suggests repeating requests for a response “every 3–6 months”. Even if the system does work, as in the case of a reviewer clearly being identified Adiano/Adobe as “appropriating” another person’s work, the COPE protocols might result in the reviewer being removed “permanently from the database”. Sadly, this isn’t anywhere nearly as sinister and dramatic as it sounds; it merely means they won’t be asked to review again by the journal from which they appropriated. I also sent letters to journals A, B and C telling them about my concerns, and asked if any of the authors of the new publication had acted as reviewers on our manuscript. The editors of Journal A and B replied immediately. They had checked on the reviewers at their respective journals, their affiliations and so on, and offered very clear assurances that they vouched for the integrity of their reviewers. In both cases the editors acknowledged the severity of the matter and were sympathetic. Journal C took another route. The editor would not directly answer my questions, and promised to refer the matter to the journal’s ethics board. After persistent prompting over many months they said the same thing again, and again, and again. Just over 6 months after I had first contacted Journal D about my concerns, I received a brief email from the editor saying that our manuscript and the suspect manuscript did not show excessive matching in their plagiarism software. That was hardly a surprise, as it was the ideas that had been appropriated. The editor also said that while there were clear similarities between the two manuscripts, they would be taking no further action. And that was that. After 6 months there would be no further investigation, and no action taken. Acknowledging the possibility that it is all a strange set of coincidences, and there really was no plagiarism (it’s all in my head), I’m not sure how even a blatant case of appropriation (even the language is weak) would be detected and then sanctioned. The current system is premised on trust. Sadly, for me at least, trust is in short supply nowadays. Stephen Moston is an Associate Professor in Psychology at CQUniversity.
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NEUROPSY
Tim Hannan
The Mystery of Agatha’s Amnesia A popular fictional theme, psychogenic amnesia is a possible consequence of stress or trauma. A sudden attack of amnesia for one’s own identity has been popular grist for the Hollywood mill, with films such as Total Recall, XMen and the Jason Bourne series all revolving around the protagonists’ inability to recall much of their personal histories. Indeed, the number of movies about this unusual type of amnesia has exceeded the count of well-documented cases in the psychological literature, and its apparent rarity and inexplicability has led to suspicions that sufferers were fabricating their symptoms – as happened to the crime novelist Agatha Christie in 1926. A new review in the journal Brain has identified more than 50 cases in a 20-year period at one London hospital, suggesting that this form of amnesia may not be quite as rare as previously thought. Amnesia is most commonly observed after a neurological illness or injury, or as a consequence of the onset of dementia. In such cases, the person loses the ability to lay down new memories (anterograde amnesia) and struggles to recall certain memories from before the onset of the condition (retrograde amnesia). Usually, the amnesia for past events relates to specific facts or details, and is more prominent for recent events rather than longheld and well-learned facts. The neural damage is typically located in the medial temporal lobes, including the hippocampus. In contrast to these “organic” forms of amnesia, “psychogenic” or “dissociative” amnesia is understood to arise as a result of trauma or other psychological stress, and involves forgetting personal information. The sufferer is able to recall and utilise her longheld general knowledge and skills to engage with people, objects and the environment, but is unable to recall her name, family members, residence, job or other personal details. The best-known case of psychogenic amnesia, Agatha Christie, went missing for 11 days after disappearing suddenly from her home. Her car was later discovered abandoned 50 km away, and
A gift that will be valued through to next Christmas
she was eventually located in a hotel in Harrogate 350 km to the north. At that time she reportedly lacked any recall of the intervening period and didn’t recognise her husband. Newspaper coverage at the time questioned the authenticity of Christie’s claims. No doubt her fame as a writer of crime fiction encouraged such scepticism. However, a new review by clinicians from a London hospital demonstrates that her symptoms were quite consistent with those observed in well-documented cases of psychogenic amnesia. They identified 53 cases admitted to the hospital between 1990 and 2008, with examination of medical records revealing much about their individual symptoms. While most sufferers reported extensive amnesia for much of their personal history, others had one or more shorter memory “gaps” involving specific events or episodes. Most cases of psychogenic amnesia included the “fugue state”. This refers to the tendency of sufferers to wander, possibly with the intention of locating people or places that may help them recover their memories. In comparison with hospital patients presenting with “organic” amnesia following neurological injuries, those with psychogenic amnesia displayed higher rates of depression, more frequent incidences of severe family or relationship difficulties, and marked financial or employment problems. Some or all of these are the presumed triggers of their amnesic episodes. Unlike the organic cases in which memory of recent events was most affected, most psychogenic patients demonstrated a consistently severe loss of memories across all time periods. The outcome for patients was generally positive, with the majority recovering their memories within weeks or months, although some had persisting gaps in their memory at follow-up years later. While psychogenic amnesia may arise following some type of stressful episode, it is far from a common consequence of trauma. Those experiencing a traumatic event are more likely to be troubled by intrusive memories or “flashbacks” than lack any memory of the trauma. The present review’s finding that most cases of psychogenic amnesia spontaneously recover is just as well, for little is known about how to treat the condition. In the absence of neural correlates of psychogenic amnesia, it may be difficult to determine whether an individual’s symptoms are authentic or feigned: it is suspected that in some cases the person is malingering to avoid an unpleasant circumstance, such as legal, financial or personal problems. Whether or not Agatha Christie’s wandering was a true case of psychogenic amnesia remains, perhaps appropriately, an unresolved mystery. A/Prof Tim Hannan is Head of the School of Psychology at Charles Sturt University, and the Past President of the Australian Psychological Society.
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THE FOSSIL FILE
John Long
When Palaeontology and Philosophy Meet The Cambrian explosion of animal diversity, evident at the Burgess Shale fossil site is fertile ground for philosophers to ponder. This year at the Annual Society of Vertebrate Paleontology Conference in Calgary, Canada, delegates could opt for two special events. I enrolled in both. The first was a 1-day field trip to the world-famous Cambrian Burgess Shale fossil site, in the high mountains of British Columbia outside Banff. The second was a “Philosophy and Palaeontology” workshop held at The University of Calgary. While it might seem both are unrelated events, they actually meshed together beautifully, especially because the field trip came first with the workshop the day after. The field trip was a long, hard day. We had to be on the bus by 4.30 am to get to the site and walk up the mountain in three groups so that only a limited number of people could each be at the Walcott Quarry to look for fossils. The Burgess Shale quarries have been a UNESCO World Heritage site since 1980 because of the incredible preservation and diversity of these Middle Cambrian fossils (505 million years old), which include a wide range of soft-bodied forms as well as typical hard-shelled creatures like trilobites and marine shells. Nonetheless, the only way to get to the site is by walking the 21 km round trip to the site and back. The site is at an altitude of about 2350 metres, and the first leg of the hike is rather steep. When some of the group turned back at that stage, we all knew we were in for a hard hike to the site. Arriving at the site around 2pm, we found the quarry set among a backdrop of stunning mountains capped by glaciers with the Emerald Lake shimmering down below us. The diversity of the Burgess Shale is extraordinary for any site this age, with at least 170 species recorded. Most of these belong to the joint-legged animals (Arthropoda comprise 59% of species known from Walcott Quarry), with sponges being the next most abundant group. Worms, molluscs, algae and other groups make up the rest. Many bizarre creatures, like Hallucigenia, whose affinities were at first unknown, characterise the assemblage. For these reasons the site has generated much debate about the “Cambrian Explosion”, the point in time when animal life diversified rapidly. While some put this down to the fact that when soft-bodied animals are fossilised it greatly increases overall diversity, it is at the higher level of animal classification that we see Cambrian life really taking off. Most of the living phyla of animals had appeared by the middle Cambrian. The nature of this diversity and how it relates to today’s living fauna is the perfect segue into philosophy. The Philosophy
The Burgess Shale’s Walcott Quarry site in British Columbia, Canada. Credit: Prof John Long, Flinders University
and Palaeontology workshop saw eminent philosophers present papers about the logic of palaeontology, with discussions developed by input from the attending palaeontologists. It was a perfect example of how science and humanities groups can work on common problems. Much of the debate honed in on the nature of the big questions raised by the Burgess Shale fossils. The late Steven Jay Gould proposed in his book Wonderful Life that we higher vertebrates are only here because of a lucky throw of life’s dice. If the precursors to fishes like Pikaia and Metaspriggina were not around in the Cambrian, we would not likely have ever evolved. There are many similar topics that philosophers like Dr Adrian Currie discuss and write papers about, from the theory of consciousness and palaeobiological laws to the luck required by palaeontologists working in the field. His blog Extinct (http://www.extinctblog.org/) provides other examples. Of course, the really big contribution to philosophy by palaeontology and evolutionary theory combined is that we humans are just the product of billions of years of evolution, and therefore are solely responsible for our own destiny on this planet. Darwin dropped this big one in 1859, and the world has either been empowered or threatened by this thought ever since. John Long is Strategic Professor in Palaeontology at Flinders University, and is current President of the Society of Vertebrate Paleontology.
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EXPERT OPINION
Australian Science Media Centre
Musk’s Mission to Mars Elon Musk provided an update on his quest to colonise Mars at the International Astronautical Congress in Adelaide, where he described a reusable rocket to overcome cost barriers and an ambitious schedule to land cargo missions on Mars by 2022. “Elon Musk’s vision for human space flight is exciting, timely, and truly fascinating. One hundred per cent reusability of rocket components, refuelling in orbit rather than on a planet or moon’s surface, and using widely accessible and inexpensive fuels like methane and oxygen are major parts of this vision. Space-X has made huge strides towards this reusability this year. The time lines are very ambitious, including setting the year 2022 for two cargo ships to go to Mars, but 5 years is also a significant amount of time. The Apollo program’s time line was not very different. If even a small part of this vision can be implemented then Elon Musk and Space-X will allow humanity to make major steps to the Moon, to Mars and beyond much faster than existing plans. Yes, there are undoubtedly major challenges to overcome, including the effects of space weather (e.g. radiation events due to solar flares) and issues with closed life support and maintenance systems, but we should explore the major potential benefits to Space-X’s approach and consider supporting the parts we deem viable and transformational.” Professor Iver Cairns is a Professor in Space Physics at The University of Sydney and incoming Director of the ARC Training Centre for CubeSats, UAVs and Their Applications.
“Elon Musk is impressive. He shows what intelligence and money can do when they are combined. Notice also that Elon Musk is not a committee. Reusing and recycling seem to be at the heart of the new approach that Musk is taking. The science behind this is realistic. The unrealistic part – the thing holding us back – has always been finding the political will to invest in space. Kennedy and the cold war found the money for NASA to get us to the Moon. Musk doesn’t need Kennedy’s eloquence... or rather Musk’s eloquence is in the deep knowledge of the physics and engineering. Musk’s vision and engineering savvy seem to be able to attract the money to build the BFR.”
Space X started in 2002, and their first three rockets failed, having the first successful launch in 2008. Last year they overcame one of the hardest hurdles in the rocket business: landing a rocket on a barge and creating a reusable rocket. This year Space X launched more rockets this year than any other space agency. But these launches, it appears, were just a practice for something bigger. Space X is working on making their current rockets and Dragon capsule redundant in place of one rocket to rule them all: the BFR rocket. The factory is built, the parts are ordered, and production will start soon. The reusability is fundamental in keeping the costs down, as well as refuelling by oxygen and methane in orbit. This one rocket will be able to service the ISS, do a return trip to the Moon without local re-fuelling, and reach Mars. It can carry 150 tonnes of fuel, which is more than the biggest rocket so far, Saturn V. The rocket will be able to land to the Moon or Mars by Falcon’s perfected retro-propulsion method. The first cargo mission with two BFR rockets is planned for 2022, and a human crew mission for 2024, and also setting fuel production on-site. We have learned to expect the impossible from Elon Mask and Space X, and this time frame is aspirational but does not seem impossible. And this time we were treated with visions of a lunar and Martian base, which makes the whole package even more mesmerising. And just as you think that is innovative enough, Elon Mask casually mentions that the same rocket will be able to fly us in under an hour wherever we want to go on Earth. What else to say but ‘the future is now’ – and it looks great.”
Make sense of science
Dr Jasmina Lazendic-Galloway is a Lecturer in the School of Physics and Astronomy at Monash University.
Dr Charley Lineweaver is an Associate Professor in the Research School of Earth Sciences at the Australian National University College of Science.
“Elon Mask is one big step closer to his dream of making humans multi-planetary species. He wants us to have a better future and to be inspired by the potentials that we have as humans. Elon is famous for his agile and efficient way of running his companies and bringing truly amazing ideas to life. But the cost of interplanetary travel is one of the main reasons humans have not set a foot beyond the Moon, so Elon Mask’s presentation focused on ‘how do we pay for this thing?’ 42 |
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DIRECTIONS
Securing Our Digital Future Our digital future depends on preparing industry and society for change. Today’s digital technologies are having a significant societal and economic impact within Australia. They are also acting as the basis of a newly emerging set of foundational technologies such as the Internet of Things, big data, machine learning and autonomous systems, which will disrupt every aspect of the economy. This digital transformation presents a range of opportunities and challenges. We must address three key areas to maximise opportunity in Information, Computing and Technology (ICT) development and application and reduce societal impact. Stakeholders across government, industry, academia and the community need to take responsibility for: • developing information and communication technologies in Australia; • advancing digital transformation for industry and government in Australia; and • evaluating the implications of digital transformation on society. The Australian Academy of Technology and Engineering (ATSE) is working to provide guidance to various sectors on the required next steps as Australia’s national capabilities in ICT and digital engineering strive to underpin growth in all Australian industry sectors, including health, agriculture, finance, mining and education. Australia’s digital future will rely upon a science, technology, engineering and mathematics (STEM) skills base. Critically, education systems must a focus on STEM, and they must evolve to meet the pace of digitalisation. Digital literacy will be essential to the process of learning, from primary school through to tertiary education. Students must have courses that teach computational thinking (e.g. mathematics and coding) as part of the curriculum, and must be exposed to entrepreneurship throughout their education in order to harness each student’s imagination, enlivening creative responses that align with the dynamic and changing real world environment. Tertiary institutions must focus on providing the skills to meet the technical and analytical needs created by increasing volumes of data. This should include courses for data scientists and analysts (already in demand) to facilitate effective information management services that ensure the availability, confidentiality and integrity of data. Courses must also produce graduates with cybersecurity skills that enable them to hit the ground running. Vocational educational systems, with strong alignment with industry and flexible and responsive course design, will be essential in accommodating emerging skills trends.
Australian Academy of Technology and Engineering
The successful uptake and effective utilisation of ICT services will continue to facilitate innovation across an increasingly diverse range of areas. Australia’s manufacturing, production and services sectors will increasingly be enabled by access to broadband, both fixed and mobile, as well as low-power network technologies for the Internet of Things (IoT). The pending boom in the number of sensors collecting huge quantities of data, which in turn must be stored, presents a range of technological opportunities. ICT has already strongly impacted societal culture and behaviour. People are increasingly moving towards living part of their lives in the digital world, including socialising, learning, conducting financial transactions, and storing and sharing personal data. Emerging technologies will see this evolution continue with a deepening of human–machine partnerships and relinquishing of tasks to autonomous systems.
Emerging technologies will see this evolution continue with a deepening of human–machine partnerships and relinquishing of tasks to autonomous systems. This level of engagement will also create a societal response as users of technology face issues around: • cybersecurity. Secure and large storage systems to accommodate the proliferation of data being collected will continue to increase in demand, with failures around this impacting on advancements and user confidence; • ownership of data. Clear ownership to facilitate adequate privacy and control will be central to some consumers and necessary for engagement in new and innovative programs as they emerge; • ethics around automation and artificial intelligence (social robotics). As technology advances there may be a lag in response from the general community until broader awareness of potential issues grow. This can result in industries and innovation being stifled or dismantled; and • privacy. The community has varying expectations around privacy. Factors related to the IoT and home safety may present issues for the development and uptake of IoT products. Australia must address these matters at the forefront of technology development – with appropriate regulatory frameworks – before they become issues rather than responding to poor outcomes after they have become issues. Professor Mike Miller AO FTSE and Professor Glenn Wightwick FTSE co-chair ATSE’s Digital Futures Working Group.
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THE BITTER PILL
Follow the Money The Chinese government is behind efforts to promote Traditional Chinese Medicine despite its lack of evidence. Federal Health Minister Greg Hunt’s recent announcement that a host of complementary and alternative medicine (CAM) practices, lacking any evidence base for their effectiveness, will no longer receive taxpayer-funded rebates for treatment. That is good news, but at the same time Traditional Chinese Medicine (TCM), similarly lacking an evidence base, is being promoted and adopted widely with strong government support. You have to ask why. In 2014, the Australian government signed an $18 billion Free Trade Agreement with China, with TCM singled out for special attention. With no definitive evidence to support claims that TCM can cure any disease or disorder, you have to ask why Australia is embracing TCM. TCMs are among the fastest growing “health” products in Australia, where the growth of TCM has been influenced by the Chinese and Australian governments, and international agencies including the World Health Organisation (WHO), our regulators and our universities. China is pushing TCM. It is a $40 billion industry in China, and TCM products are among the most profitable of all Chinese exports even though it has been in decline in China in recent decades, with 80% of people now relying on western medical treatment. To boost TCM a new Chinese law, promising equal status for TCM and western medicine, came into effect this year. Provisions include encouraging hospitals to set up TCM centres. TCM appeals because it is “natural”, but in 2015 DNA analysis of imported TCM products found that nearly nine in ten contained some form of undeclared substance, including strychnine, arsenic, snow leopard, pit viper, warfarin and Viagra. A 2017 review of nearly 500 TCM products by Hong Kong hospital toxicologists found that most contained modern pharmaceutical-grade appetite suppressants, stimulants and antiinflammatories. In 2014, 230,000 reports of adverse reactions to TCM products were received by China’s “National Adverse Drug Reaction Monitoring”. You might expect China to be at the forefront of researching TCM’s effectiveness, but while the majority of studies from China report that it’s effective, this is unreliable as negative results aren’t published, Acupuncture is included within TCM, but it doesn’t work. Cochrane reviews are the “gold standard” for evidence-based medicine, and nearly 50 reviews have failed to find robust evidence for acupuncture. A rigorously scientific review of the evidence for acupuncture by non-acupuncturists concluded 44 |
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Friends of Science in Medicine
that it was a theatrical placebo. Despite many Chinese parents considering it useless, and regarding the teaching of it as a waste of precious school time, 12-year-olds are being taught about TCM and how to administer acupuncture; government sees it as a way to boost confidence and pride in China. More than 700,000 TCM textbooks are being distributed to schools. The WHO is also involved. Quoted worldwide as “evidence”, a 2002 WHO publication on acupuncture claimed that it is “clinically proven to be effective” or “effective” for more than 90 disease and disorders, including depression, dysentery, induction of labour, rotating breech-position babies, rheumatoid arthritis, stroke and whooping cough. For the past decade, Margaret Chan was the DirectorGeneral of the WHO. A Chinese-Canadian physician, she uses TCM, and urged the Chinese government to promote TCM worldwide, claiming it could “reduce the burden on health services”. Australian regulators are also to blame. As part of the Department of Health, the Australian Therapeutic Goods Administration’s role is to safeguard the health of Australians “through effective and timely regulation of therapeutic goods”. However, the latest proposed changes to their advertising code include more than 1000 TCM and traditional indications, such as “harmonise middle burner (spleen and stomach)”, “unblock/ open/relax meridians”, “balance yin and yang”, “renal tonic” and “helps healthy liver regeneration”. Collaboration with Chinese institutions is bringing millions of dollars into our universities. These collaborations aim to integrate TCM “research into a clinical setting,” supposedly to “accelerate the development of more effective treatments for the most pressing and costly chronic health problems facing the world”. China wants to grow its exports of TCM by influencing governments, universities and regulators. Australian business wants to tap into the $170 billion global TCM market. This is not about improving our health and well-being, but about growing Chinese business influence internationally and boosting the Chinese economy. The chronically ill and other vulnerable patients pay the price. Here in Australia, Friends of Science in Medicine has made some progress. The links to the acupuncture report have been removed from the WHO website. The Chinese Medicine Board of Australia has published a statement that “acceptable evidence to support advertising claims needs to be based on findings obtained from quantitative methodology such as systematic reviews of randomised and high quality controlled trials”. However, with no way to modify TCM practitioners’ scope of practice, for those who venture into their local TCM clinic it will remain “business as usual”. Loretta Marron is the Chief Executive Officer of Friends of Science in Medicine.
THE NAKED SKEPTIC
Peter Bowditch
Counting the Opinions The same sex marriage survey repeats the statistical mistakes of most opinion polls. People who might never have heard of George Santayana would still be familiar with the quote: “Those who cannot remember the past are condemned to repeat it”. Australia has been going through a process that repeats mistakes from the past. The 1936 US presidential election was between the incumbent Democrat Franklin D. Roosevelt and Republican Alf Landon, Governor of Kansas. Roosevelt was partway through implementing his New Deal program, something which was seen by many conservatives as ushering in a form of socialism and anathema to those who saw libertarianism, small government and individual personal freedom as the foundations of US polity. The magazine The Literary Digest mailed out about 10 million survey forms to subscribers and others, asking them to predict who would win. The 2.3 million replies suggested that Landon would win 370 of the 531 Electoral College votes, and therefore the Presidency. Yet Roosevelt received 500 Electoral College votes and more than 60% of the popular vote.
Although everybody on the electoral roll has been sent a survey form, participation is optional so only people really motivated by the question will feel the need to respond.
So how did The Literary Digest get the prediction so wrong? One suggestion was that the subscriber base of the magazine consisted predominantly of conservative voters, so they were the wrong people to ask. The real problem, however, was a combination of this and also that the respondents were a self-selected sample of people motivated enough to fill in a form, put it in an envelope and go to a postbox to return it. Another player in 1936 was advertising executive George Gallup, who thought that there was a scientific way of predicting the results of the election. Using a sample of 50,000 people he said that Roosevelt would win. I remember having hammered into me in the first statistics courses I did at university the importance of sample selection, and how samples had to be both random and representative of the population under study. These might seem conflicting ideals, but it is possible to randomly select subjects while still ensuring that the overall sample is representative.
Large amounts of advertising expenditure and media company profits are based on television and radio ratings. These ratings are based not on counting everybody who watches a particular television program but on monitoring the behaviour of a very carefully selected sample of a couple of thousand people across the country. Political polling can be very accurate with a small sample, but that sample is drawn from every electorate in the country. (The 1975 Australian Federal election that followed the dismissal of the Whitlam government was one of the most polarised in history. The newspaper Nation Review had a competition to predict the relative percentages in two-party preferred voting for the Senate. The winner, who got the percentages correct to the third decimal place, worked for the Gallup organisation and used the figures from an opinion poll a week before the election.) Australia is in the midst of a massive opinion poll to answer a single question: should the law be changed to allow same-sex couples to marry? Showing that we have learnt nothing from the lessons of 1936, the survey is being conducted as a postal vote. Although everybody on the electoral roll has been sent a survey form, participation is optional so only people really motivated by the question will feel the need to respond. Motivation to express an opinion might not even be enough. I live in a small country town with approximately half of the residents of the local government area living on farms outside the town. There appears to be only one postbox in the entire area for people to return their voting papers, and I’ve spoken to many people who only come into town about once a month to do shopping. If you don’t post a lot of letters it’s easy to forget that you need to take one with you the next time you go for groceries. Three weeks after the first voting forms were posted out there were three estimates of the response rate. Two surveys conducted by private pollsters with sample sizes of about 1000 suggested that approximately 75% of the forms had already been returned. The Australian Bureau of Statistics said in the same week that 57.5% had been returned. The ABS figure was itself an estimate based on counting envelopes in a few boxes and extrapolating to a warehouse full of boxes; if about 25% of the votes were coming in per week then just a few days delay in postal delivery could account for the difference between the two estimates. I’ve posted my vote, but I’ll have to wait until mid-November like everybody else to see the result (and of course the ABS analysis of the validity of the count). I hope we get value for the large amount of money the survey cost. Peter Bowditch is a former President of Australian Skeptics Inc. (www.skeptics.com.au).
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ECOLOGIC
Laura Mumaw
Grow Your Own Collaborative wildlife gardening programs engage residents to manage their land and achieve landscape-focused conservation goals. Involving communities in appreciating and caring for nature is a key goal in most conservation strategies. But how is this achieved, particularly in cities where “nature” is sometimes hard to come by? Wildlife gardening is one commonly suggested solution, but what ingredients make for a successful program? Although the urban landscape is dominated by human activities and cannot be restored to a wild state, the persistence of native flora and fauna can be fostered. Effective conservation of native species requires sympathetic management of plots of public and private land in a way that protects and improves patches of native habitat (generally on public land). This is enhanced by establishing protective buffers around them and improving connectivity between them through corridors and stepping stones in residential and other land-use areas. Residents may feel this is the responsibility of experts and parks staff, or that they have little to offer. Yet residential gardens are important: they make up a large proportion of urban land, many community members have them, and they can provide habitat that is important for the survival of native species. Unfortunately there is currently little guidance about how best to involve residents in wildlife gardening and align their work with public land management. To help fill this hole, we looked at how a partnership in greater Melbourne between Knox City Council and a community group (Knox Environment Society) involves residents in gardening to help conserve the biota native to the municipality. The wildlife gardening program, Knox Gardens for Wildlife (G4W), began in 2006 and currently has more than 700 participating households (http://tinyurl.com/y8fdt9jz). We interviewed 16 G4W members of varying ages, backgrounds, gardening experience, property characteristics and time in the program to understand what program features motivated and supported them to change their gardening to assist the Knox City Council and Knox Environment Society to foster locally native (indigenous) species. We supplemented the interview data with a Council survey of the G4W membership. So what motivates people to make an effort to get into wildlife gardening? We found that program features instrumental in supporting wildlife gardening are an inspiring faceto-face garden assessment; a community nursery to which members can return to for advice and support; communication hubs, including the nursery and Council offices; a framework that fosters experiential learning and community linkages; and endorsement by Council and Knox Environment Society of each garden’s potential conservation contribution. 46 |
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The superb fairy-wren feeds on insects and small grubs, and will often appear in small groups in suburban gardens with dense, low, native shrub cover. Wildlife gardening programs have potential to enhance our home gardens to be more wildlifefriendly. Credit: Geoff Park
Interviewees with or without prior intention or knowledge of wildlife gardening became involved. What was common to all of them was an interest in keeping a garden. We conclude that wildlife gardening programs with community features can engage urban residents to manage their land to help council and community to conserve indigenous biota. The hands-on involvement of community members and local government is critical to stimulate interest and support for municipal biodiversity conservation. Beyond stimulating and supporting members to wildlife garden, the program builds relationships between participating members, the community group and council around a shared interest in fostering the municipality’s wildlife. In part informed by research from this study, the Gardens for Wildlife Victoria (https://gardensforwildlifevictoria.com/) pilot program has been initiated to support urban local government–community group partnerships to engage local residents in caring for nature through gardening and other habitatimprovement activities. A consortium that includes the Victorian Department of Environment, Land, Water and Planning, a regional catchment management authority, and local government and community group members has been established to lead the initiative. Their intent is to help make Victoria’s new biodiversity strategy understood and pragmatically applied in urban communities, and to develop research tools and knowledge about how to facilitate community engagement in fostering biodiversity while strengthening social cohesion. Laura Mumaw is a member of the ARC Centre of Excellence for Environmental Decisions. She is based at RMIT University in Melbourne.
LOWE TECH
Ian Lowe
Lift-off for Space Agency The re-establishment of an Australian space agency is expected to generate billions of dollars after decades of neglect of the sector. Australia is at last going to have its space agency restored. The decision was announced at a major international conference in Adelaide in September. Scientists working in space-related areas greeted the announcement with unanimous enthusiasm after governments had been missing in action for more than 20 years. The Australian Space Office was set up in 1987, when Barry Jones was Science Minister. It had a modest annual budget of $5 million, but there were big space projects under consideration at the time: restoring Woomera’s capacity to launch rockets, or building a massive space port on Cape York. Prime Minister John Howard closed the Space Office when he was elected in 1996, a move showing he had neither vision nor respect for science. Twelve years later, a parliamentary committee said it was no longer acceptable for Australia to be “lost in space” yet nothing happened. The current industry minister, Arthur Sinodinos, appointed former CSIRO chief Dr Megan Clarke to conduct another inquiry. It is due to report next March, but the international conference put pressure on the government to act. Critics pointed out that Iceland was the only other OECD country without a space agency. Barry Jones was more direct, noting that New Zealand has one, as do Peru and Nicaragua! So the Turnbull government rushed to make an announcement to the conference. One report said the minister’s remarks were almost drowned out by cheers when he said that a space agency would be established. We really need to see the terms of reference and funding level. Dr Bruce Middleton, who first headed the space office 30 years ago, told The Saturday Paper that the new agency will need at least $50 million per year to be effective. Dr Allan Duffy of Swinburne University of Technology said that the space sector is worth $3–4 billion in Australia, a figure that he expects could be doubled by an effective agency. The scientists and commercial interests involved will be watching next May’s Federal Budget with great interest. The latest edition of the national emissions inventory makes chilling reading. The report was produced for Canberra think tank The Australia Institute by energy expert Dr Hugh Saddler. It shows that Australia’s greenhouse gas emissions are still increasing rapidly despite our endorsement of the Paris agreement to slow climate change. Our emissions are now at a record level. Turkey is the only other advanced country releasing more greenhouse gases now
NASA/Goddard Space Flight Center Scientific Visualization Studio
than when the climate change treaty was negotiated 25 years ago. All other developed countries, even the USA, have made progress. The fine print exposes the folly of the national government’s attempt to prolong the life of an old and dirty coal-fired power station. Our transport fuel use is increasing, an inevitable consequence of rapid population growth and continuing neglect of public transport. With no realistic prospect of reining in transport emissions before 2030, meeting our Paris obligations demands a more rapid transition to clean electricity than the government proposes. The Australia Institute concludes the least-cost solution to meet our Paris target requires 66–75% of power from renewables by 2030. The ALP’s national target of 50%, and similar targets in some states, have been criticised by the Coalition government as too ambitious. But the new analysis shows that really drastic measures will need to be taken to reduce emissions from transport, manufacturing and agriculture if we don’t take the more cost-effective action of cleaning up electricity supply. Saddler’s analysis confirmed that electricity production from coal and gas failed to meet energy demand during the February heatwave. He noted that the power system has a peak load problem rather than a baseload problem. “Right when NSW consumers needed them most, important gas and coal generation went missing in action,” Saddler said. This strengthens the case to move towards renewables with storage, rather than extending the life of old baseload power stations. It also reinforces the need to get serious about improving the efficiency of energy use, as the National Framework report recommended 14 years ago. That is not low-hanging fruit; it is fruit lying on the ground that really should be picked up. Improving efficiency saves money as well as reducing emissions. Ian Lowe is Emeritus Professor of science, technology and society at Griffith University.
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OUT OF THIS WORLD
David Reneke
Bringing Building Blocks of Life to Earth from Space How life began on Earth, roughly 4 billion years ago, is one of the great scientific questions. New results from scientists at McMaster University and the Max Planck Institute for Astronomy suggest a key role for meteorites landing in warm little ponds, delivering essential organic molecules that kickstarted the emergence of life in the shape of self-replicating RNA molecules. The astronomers reached their conclusions after assembling models about planet formation, geology, chemistry and biology into a coherent quantitative model for the emergence of life. The most interesting result from these calculations is that life must have emerged fairly early while Earth was still taking shape. This, they maintain, was only a few hundred million years after the Earth had cooled sufficiently to allow liquid surface water, such as ponds or oceans. The building blocks of life would have been brought to Earth by meteorites during an era when Earth’s bombardment by such small extraterrestrial rocks was much more intense than today. Astronomers agree that in order to understand the origin of life we need to understand Earth as it was billions of years ago. As this study shows, astronomy provides a vital part of the
The theory holds that either very simple forms of life or the materials necessary for it to form are carried to Earth on comets or fragments of asteroids. Credit: Science Photo Library/Getty Images
answer. The details of how our solar system formed have direct consequences for the origin of life on Earth. The new work supports the “warm little pond” hypotheses for the origin of life, with RNA polymers forming in shallow ponds during cycles in which the pond water evaporates and is refilled periodically. It shows how meteorites could have transported a sufficient amount of nucleotides to thousands of such ponds on Earth, helping to kickstart life in at least one of those ponds. “We have provided plausible physical and chemical information about the conditions under which life could have originated,” said Dmitry Semenov of the Max Planck Institute. How true! Now it’s the experimentalists’ turn to find out how life could indeed have emerged under these very specific early conditions.
How a Galaxy’s Spin Affects Its Shape For the first time Australian astronomers have measured how a galaxy’s spin affects its shape. It sounds simple, but measuring a galaxy’s true 3D shape is a tricky problem that astronomers first tried to solve 90 years ago. “This is the first time we’ve been able to reliably measure how a galaxy’s shape depends on any of its other properties, in this case its rotation speed,” said research team leader Dr Caroline Foster of The University of Sydney, who completed this research while working at the Australian Astronomical Observatory (AAO). There’s one thing astronomers agree on: galaxies can be shaped like a pancake, a sea urchin, a football, or anything in between. Faster-spinning galaxies are flatter than their slower-spinning siblings, the team found. It’s simply a rule the universe works by. The team’s findings show that among spiral galaxies, which have discs of stars, the faster-spinning ones have more circular disc shapes. The team made its findings with SAMI, an instrument jointly developed by The University of Sydney and the Australian Astronomical Observatory with funding from the ARC Centre of Excellence for All-Sky Astrophysics (CAASTRO). SAMI gives detailed information about the movement of gas and stars inside galaxies. This instrument has a wide grasp; it can examine 13 galaxies at a time and thus collect information about huge numbers of them. The result is a bigger data base to work with. Foster’s team used a sample of 845 galaxies, over three times 48 |
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Credit: University of Wyoming
David Reneke is an astronomy lecturer and teacher, a feature writer for major Australian newspapers and magazines, and a science correspondent for ABC and commercial radio. Subscribe to David’s free Astro-Space newsletter at www.davidreneke.com
At last the dynamics of galaxy rotation are becoming clearer.
more than the biggest previous study. This large number was the key to solving the shape problem. Because a galaxy’s shape is the result of past events such as merging with other galaxies, knowing its shape also tells us about the galaxy’s history. In a way it’s sort of like “archaeo-astronomy” by backtracking on what went before in an effort to understand what we have now. It’s a new study so watch this space!
QUANDARY
Last-Minute Complications Botched executions provide a timely warning that assisted suicide does not necessarily lead to a peaceful death. The gold standard for experiments on human beings is a randomly assigned double-blind placebo-controlled study. Naturally, organising one of these to assess the effectiveness of lethal drugs is unlikely. Unless you live in North Korea, the chances of getting approval from an ethical review committee is very low. Instead, we need to rely upon experience from the United States. And this suggests that there can be glitches in choosing the date of one’s death. In a recent issue of the Journal of Law and the Biosciences, Sean Riley, an end-of-life researcher currently studying in The Netherlands, reviewed the patchy record of the drugs used in executions and physician-assisted suicide (PAS). He summarises his findings as follows:
The pervasive belief that these, or any, noxious drugs are guaranteed to provide for a peaceful and painless death must be dispelled; modern medicine cannot yet achieve this. Certainly some, if not most, executions and suicides have been complication-free, but this notion has allowed much of the general public to write them off as humane, and turn a blind eye to any potential problems. Executions or PAS have never been as clean as they appear, even with the US’s medicalization efforts during the 1980s.
His research gives a different spin to arguments put forward by supporters of assisted suicide in Australia and elsewhere. While the horrors of botched executions in the American midWest are reported around the world, complications with death by PAS are barely mentioned. Yet they use basically the same drugs, so it is worthwhile discussing them in tandem. Riley addresses several practical problems about the drugs. They are most evident in capital punishment, but there is a flow-on effect to PAS. Supplier Boycotts Under pressure from anti-death penalty activists, pharmaceutical companies in the US and abroad have refused to supply prisons with the drug of choice for executions, pentobarbital. Efforts to circumvent this by going to shady middlemen eventually failed. Nowadays most states have ceased to import the key ingredients needed for executions. Price Gouging for PAS Drugs Because of the drought of lethal medications for executions, the price of pentobarbital in liquid form for PAS has skyrocketed. “Before 2012, patients would pay about US$500 for a sufficient lethal dose of the drug, but by 2016 prices had inflated
Michael Cook
to figures upwards of $25,000,” says Riley. A lethal dose of the other effective and popular drug, secobarbital, cost about US$200 8 years ago but Valeant, a Canadian pharmaceutical company, bought the drug and jacked up its price to $3,000. Compounding Pharmacies Faced with the huge cost of assisted death, prisons and patients began to turn to compounding pharmacies where pharmacists create the drugs from raw materials. “As the past three or so years have seen a dramatic increase in the use of compounded drugs,” writes Riley, “there has been a corresponding rise in ‘botched’ executions, though the secrecy laws have neutered most attempts to link failed executions to compounded drugs”. Drugs made in compounding pharmacies risk being not strong enough or too strong – or contaminated. In Massachusetts a former pharmacist is on trial for supplying contaminated drugs that caused a nationwide outbreak of meningitis. Prosecutors told the court that he had used expired ingredients, falsified documents, neglected cleaning, failed to properly sterilise the drugs, shipped products before they were tested, and ignored mould and bacteria in manufacturing areas.
As Australia debates assisted suicide, it’s important to keep in mind that the case for Yes and the case for No can both involve undue pain.
Last-Minute Complications It is difficult to define what a “botched execution” is, but the dying moments of some prisoners were clearly agonising. And there are complications with PAS as well, although the data is a bit murky. “According to data published by Oregon, 5% of patients experienced difficulties, such as regurgitation or seizures, after ingestion of the medication, since the inception of the law in 1997,” says Riley. However, the details were reported in only 51% of the cases, and “there are six reported instances where patients ingested the lethal medications, went unconscious, and awoke sometimes days later”. As Australia debates assisted suicide, it’s important to keep in mind that the case for Yes and the case for No can both involve undue pain. Riley’s philosophical conclusion is: “The processes of death will always, to some extent, be a mystery. For now, whether a death is peaceful and painless can only be assumed.” Michael Cook is Editor of BioEdge, an online bioethics newsletter.
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AUSTRALASIAN SKY
November 2017 STAR BRIGHTNESS Zero or brighter st 1 magnitude 2nd 3rd 4th
Andromeda Galaxy
GREAT SQUARE OF PEGASUS M15
First Quarter Moon on the 27th Mira
BOOTES CORONA BOREALIS
Arcturus M8 M28
Regulus M19
P
P
SATURN
MERCURY
47 Tucanae Zubenelgenubi
Antares
SCORPIUS
CHART KEY
CENTAURUS Omega Centauri POINTERS
NORMA TEA POT
Bright star Faint star Milky Way Ecliptic Celestial Equator P Planet LMC or Large Magellanic Cloud SMC or Small Magellanic Cloud
Alpha Centauri POINTERS
α
TRIANGULUM AUSTRALE
CRUX
β β α
γ
SOUTHERN CROSS
εδ
Proxima Centauri APUS
SOUTHERN CROSS
MOON PHASE Full Moon Last quarter New Moon First quarter
04th 11th 18th 27th
OCTANS
THE CHART
HIGHLIGHTS IN NOVEMBER 2017
The star chart shows the stars and constellations visible in the night sky for Sydney, Melbourne, Canberra, Hobart and Adelaide for November 2017 at about 8.30 pm (local daylight saving time) or about 7.30pm (local standard time) for Perth and Brisbane. For Darwin and similar northerly locations the chart will still apply, but some stars will be lost off the southern edge while extra stars will be visible to the north. Stars down to a brightness or magnitude limit of 4.5 are shown on the star chart. To use this star chart, rotate the chart so that the direction you are facing (north, south, east or west) is shown at the bottom. The centre of the chart represents the point directly above your head, called the zenith point, and the outer circular edge represents the horizon.
The best time to look at the Moon with a small telescope or binoculars is a few days either side of its first quarter phase, which falls on the 27th of November. Saturn is low in the west, starting in Ophiuchus (the Serpent Bearer), but moving to Sagittarius (the Archer) as the month progresses. Mercury is also low in the west, through November moving from Libra (the Scales) through Scorpius to Sagittarius. Crux (the Southern Cross) is located to the south, near the horizon, making it difficult to see at this time of year. Pisces (the Fish) and Aries (the Ram) are located in the eastern sky, while the great square of Pegasus can be found in the north.
Sydney Observatory is part of the Museum of Applied Arts and Sciences. The Sydney Observatory night sky map was created by Dr M. Anderson using the TheSky software. This month’s edition was prepared by Melissa Hulbert. © 2017 Museum of Applied Arts and Sciences, Sydney.
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AUSTRALASIAN SKY
December 2017 STAR BRIGHTNESS Zero or brighter st 1 magnitude 2nd 3rd 4th
Andromeda Galaxy
M45 - Pleiades
Hyades
First Quarter Moon on the 26th
Orion’s belt
1
“The Saucepan”
Fomalhaut
Tarantula Nebula
False Cross
Chart Key Bright star Faint star Ecliptic Milky Way P Planet LMC or Large Magellanic Cloud SMC or Small Magellanic Cloud
Diamond Cross The Pointers Southern Cross
MOON PHASE Full Moon Last quarter New Moon First quarter
04th 10th 18th 26th
THE CHART
HIGHLIGHTS IN DECEMBER 2017
The star chart shows the stars and constellations visible in the night sky for Sydney, Melbourne, Canberra, Hobart and Adelaide for December 2017 at about 8.30 pm (local daylight saving time) or about 7.30pm (local standard time) for Perth and Brisbane. For Darwin and similar northerly locations the chart will still apply, but some stars will be lost off the southern edge while extra stars will be visible to the north. Stars down to a brightness or magnitude limit of 4.5 are shown on the star chart. To use this star chart, rotate the chart so that the direction you are facing (north, south, east or west) is shown at the bottom. The centre of the chart represents the point directly above your head, called the zenith point, and the outer circular edge represents the horizon.
The summer solstice is on the 22nd, when the Sun reaches its highest point in the sky for the year, and this day has the most hours of daylight. The best time to look at the Moon with a small telescope or binoculars is a few days either side of its first quarter phase, which falls on the 26th of December. Saturn and Mercury start low in the west in Sagittarius (the Archer) but vanish in the twilight early in the month, leaving no bright evening planets. Crux (the Southern Cross) is located to the south, near the horizon, making it difficult to see at this time of year. The summer constellations of Orion (the Hunter) and Taurus (the Bull) are in the northeast. Sirius, the brightest night-time star, is low in the southeast.
Sydney Observatory is part of the Museum of Applied Arts and Sciences. The Sydney Observatory night sky map was created by Dr M. Anderson using the TheSky software. This month’s edition was prepared by Melissa Hulbert © 2017 Museum of Applied Arts and Sciences, Sydney.
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