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CONTENTS
Issue 14 Lent 2009
FEATURES A Colourful World
Katherine Thomas looks at the vibrant properties of iridescence ......................................................................................
More than a Flight of Fancy
Matt Child explains the role of birds in our ecosystems ......................................................................................................
Just Empty Space?
Lara Sibley unravels the extraordinary properties of a vacuum .........................................................................................
Sounding Out a Cure
Moira Smith looks at new developments in the fight against cancer .................................................................................
A Single Defective Gene
Beth Ashbridge looks at the science and dehumanising effects of Huntington’s disease ...........................................................
8 10 12 14 22
FOCUS..................16 SUPERHUMAN...in pursuit of perfection As science and technology progress, the unimaginable is becoming possible. This issue’s FOCUS looks at where we’ve come from and where we’re going.
REGULARS News On the Cover Book Reviews Technology Undergraduate A Day in the Life of... Away from the Bench Arts and Reviews History The Pavilion Initiatives Dr Hypothesis
Scientific Soundbites ............................................................................... A Closer Look ........................................................................................ Totality ...................................................................................................... Electronic Paper ...................................................................................... Your Research Projects .......................................................................... Nobleprize.org ........................................................................................ Stories from CERN ................................................................................ That’s so Random ................................................................................... The Evolution of Natural Selection .................................................... Science Inspires Art ................................................................................ From the Experts to Everyone ............................................................ Answers to Your Scientific Stumpers .................................................
4 5 6 7 21 24 25 26 28 30 31 32
New Naturejobs Podcasts Launch of The Source Event Podcasts 2008 Listen to expert speakers from the Naturejobs career fair ‘The Source Event’. In the first show, high-profile scientists from the worlds of academia and industry offer a taster of the many opportunities available to young researchers.
Download the December podcast for FREE now at source-event.com. An interview with…
• Dr Chris Kirk – Biochemical Society • Paul Matts – Procter and Gamble • Sandrine Pouly – Merck Serono
New shows released each month at www.source-event.com. Sign up to the RSS feed to keep up-to-date! Coming soon: • • • • • • • • • • • • •
Simon Frantz – Careers in science writing/editing Bernd Pulverer – How to get published Zonya Jeffrey – NGOs: save the world and keep a career Martyn Poliakoff – Choosing a mentor Dr Adam Staines – Hints and tips on successful grant applications Vanessa Diaz-Zuccarini – How important is mobility for young scientists? Dr Clive Hayter – Science policy and the funding landscape George Schlich – Careers in the legal profession Stijn Oomes – Building your network Sima Adhya – Dream job: Senior Technical Officer, Space Matthias Haury – How to set up a lab and manage it Dr Elizabeth Allen – CROs: different route into industry Paul Matts – Dream job: Skin Care Expert
More about The Source Event
The Source Event is an annual dedicated science career fair hosted by Naturejobs. Exciting debates and informative discussions take place throughout the day with sessions split into three main streams Graduates, Postdocs and those interested in information about non-traditional science careers.
For more information please visit www.source-event.com
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EDITORIAL
Chris Adriaanse Editor
we’re gOINg to be incapable of avoiding a few of the celebrations taking place this year. The University completes its eighth centenary and it’s been 200 years since the birth of Charles Darwin. For the first issue of the year, BlueSci tried to avoid all this. There’s simply too much to compete with. so if you want a break from all that, then settle down with a copy and have a read. Instead of the familiar story of Darwin, we’ve told that of alfred russell wallace who also discovered evolution by natural selection during the same period and forced Darwin to publish his work. rather than charting the
illustrious scientific legacy of the University, we look to the future with e-paper in our Technology regular, as well as the choices available to enhance ourselves in our “superhuman” Focus article. elsewhere in the magazine, there’s plenty to choose from. we chart the influence of birds on our ecosystems, new treatments for cancer and a very personal account of Huntington’s disease, as well as many other stories.
Amy Chesterton Managing Editor New Year’s eve has only just passed and it already seems a distant memory.Yet again, promises of a detox diet, an exercise regime and the new work ethic lasted less than the average hangover. and as we start term there are going to be even more reasons to ignore that list of resolutions. But why not make this year different? Follow up those good intentions and try something new. Here at BlueSci, we have lots of opportunities to get involved. Join our magazine team and apply yourself to writing, editing, graphics or production. we’re always Lent 2009
looking for fresh ideas and enthusiasm. There are plenty of chances to leave your mark on Cambridge’s top science magazine. we also boast a dedicated film team, producing high quality video and audio podcasts. Once we train you up to use our professionalstandard equipment, you can freely explore your own ideas. If it’s a faster pace you’re after, our news team produce weekly round-ups of science stories throughout term time. so fill that gap in your schedule! Check us out online (www.bluesci.org) or email me (managing-editor@ bluesci.org) for further details.
Issue 14: Lent 2009 Editor: Chris Adriaanse Managing Editor: Amy Chesterton Business Manager: Michael Derringer
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NEWS
Research published in Geology has finally shed light on a 500 millionyear-old riddle: how the soft-bodied fossils found in the Burgess Shale came to be preserved in the face of prolonged exposure to extreme heat and pressure. The abundance of well-preserved fossils in this region of the Canadian Rocky Mountains has flummoxed scientists for decades; the fragile bodies of the animals should have been destroyed long ago by the 300°C temperatures and huge pressures experienced as sediments were driven deep into the Earth’s crust or by the intense heat and force generated as the Rocky Mountains were thrust up from beneath them. In spite of
Animal Testing Alternative
DAN TUCKER
Tissue cultures are being developed to reduce the need for live animals in infectious disease research. Researchers at the Department of
The microscopic structure of airway lining is maintained and alive after 24 hours of tissue culture on abattoir waste
An Entrepreneur’s Brain The difference between an entrepreneur and a manager is the ability to take risky decisions, claims Prof. Barbara Sahakian and her colleagues from the University of Cambridge in a recent commentary in Nature. The researchers asked a group of 16 entrepreneurs from the Silicon Fen in
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these harsh conditions, the fossils have somehow survived. After meticulously re-examining specimens found at the site, the team of scientists from Cambridge and Leicester concluded that contrary to previous theories, the intense heat, rather than obliterating the soft-bodied fossils, was actually crucial for their preservation.They have shown that as the delicate organic tissues of the animals were heated, they became a site for mineral formation.These new minerals then allowed delicate features such as eyes and gills to be picked out and hence preserved over millions of years. Normally, only the hard parts of animals such as bones and teeth are fossilised, leaving no trace of the soft tissues. The Burgess Shale, however, contains a great number of fossils of soft-bodied animals including the
peculiar-looking five-eyed Opabinia. The diverse array of fossils found at this site has offered a unique insight into the Cambrian explosion: the evolutionary burst of complex animal life that occurred around 550 million years ago. LL
Veterinary Medicine, University of Cambridge, are using tissue samples from the airway linings of cattle and sheep slaughtered for human consumption. By keeping the tissues alive, it is hoped these cells will provide a useful model of hostpathogen interactions. Research has shown that the ‘dead’ tissue cultures mount an equivalent inflammatory response when exposed to respiratory pathogens. Work carried out using these samples has included looking at how certain bacteria stick to the epithelium, and the changes in gene expression that take place in the mammalian cell as a result. Cell culture on abattoir waste avoids the much-debated issue of animal testing, as well as saving time
and money. Despite this, there are undeniably real challenges in the field of infectious diseases that cannot be dealt with in any system other than a live animal. For now, this work allows reliable modelling of the early pathology of infection, and towards the reduction, refinement and replacement – the 3 Rs – of the use of live animals in research. “The model [abattoir waste] does provide a real opportunity to reduce the number of animals used in infectious disease research,” said Dr Dan Tucker, one of the researchers. “This model can act as an early screen in preclinical development of new products, enabling researchers to avoid unnecessary experiments in live animals.” AZ
Cambridge and their non-founding managerial counterparts to complete neurocognitive assessment tasks. They found that entrepreneurs had highly adaptive risk-taking behaviour and showed ‘functional impulsivity’ enabling them to make quick decisions under stress. The decision making was classified as ‘hot’ and ‘cold’: cold processes are emotionally neutral with no prospect
of reward or punishment whereas hot processes have emotional significance and loss or reward associated to them. During the hot decision making the entrepreneurs were found to take higher risks. These cognitive processes are related to levels of a neurotransmitter called dopamine, raising the possibility of enhancing entrepreneurship with drugs that target dopamine levels. SS
ALEX PAGE
Fossil Problem Solved
Fossil of a primitive lace crab preserved with the blood and bodily fluids that leaked shortly after its death
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ON THE COVER
A Closer Look
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Colour in Nature Iridescence explained
Inside a Vacuum
More than we thought
Chris Adriaanse interviews Pauline Aitken, the artist behind our cover image in which to see “incredible and intriguing structures all over a plant”. This led to a collaboration with dr Jeremy Skepper and a Wellcome Trust Sci-art grant. She has spent the last
“Pauline’s work varies from the representative to the abstract” three years working in the department of Physiology, development and neuroscience where some of her work has been showcased, providing new material for people to engage with and adding colour to the walls. “People have been really enthusiastic about the exhibition here. There’s been a really good response. i’ve done three or four turnovers of the work,” she says. Pauline’s work varies from the representative to the abstract. Sometimes she uses the image as a starting point or makes digital montages, creating a “strangeness and a distortion from reality,” so that only
Alfred Russell Wallace
Randomness . Electronic Paper . Huntington’s Disease Stories from CERN . Birds . Ultrasound Therapy
as you look closely will you begin to recognise the source material. her current work has been exploring the relationship between the foxglove and the heart. This interest grew from learning that the foxglove is a source of digoxin and digitalis used to treat abnormal electrical activity in the heart. Keenly aware of the relationship between plants and medicine, she has been exploring their relationship through art. despite being a freelance artist, Pauline says science has always interested her. forced to specialise at eighteen, she chose art, but has always felt the influence of science. “The source material throughout my life has always been botanical – plant systems, plants regulation, water uptake, the interchange of gases – all that stuff has fascinated me.” Science and art, seemingly worlds apart, have always had overlap for Pauline: “i just use what i happen to find interesting and that happens to be where art and science meet.” Chris Adriaanse is a PhD student in the Department of Chemistry
PAULINE AITKEN
MICHAEL MAGGS
a deforMed petal of a Snake’s-head fritillary, Fritillaria meleagris, graces this term’s cover. The image was taken with a scanning electron microscope and later coloured by Pauline aitken. While examining a number of flowers, Pauline came across the deformed petal. Unsure whether it had been damaged by the weather or had just not grown properly, she placed it in the microscope and saw the detailed rollover of tissue. The whole petal was damaged and the extent was highlighted by the micrograph images. The petal surface was uneven, looked corroded and erupted in craters rather than the normal smooth surface. Pauline’s full piece entitled “Petal” as well as the original petal can be seen at the bottom of the page. Pauline has always been fascinated by the natural world and with plants in particular. always wanting to see more, she started making observations with a magnifying glass, progressing to microscopes to reveal more detail. only with a grant from the arts council was she able to harness the imaging power of a scanning electron microscope, unlocking another world
Darwin’s Competitor
PETAL. 2004. Ink-jet print on paper. Colour enhanced scanning electron micrograph. 430 mm x 580 mm
Lent 2009
5
BOOK REVIEWS A total SOLAR eclipse is one of the most spectacular natural phenomena, which should have undoubtedly secured a place in your check-list of things to see during your lifetime. The third edition of Totality: Eclipses of the Sun, first published in 1991 to mark the total solar eclipse that passed directly over the observatory complex in Hawaii, continues to prove itself to be an indispensable guide and reference book for solar eclipse observation today.
“The book successfully captures this beautiful natural occurrence” Totality covers every aspect of solar eclipses and addresses a wide audience with an interest in astronomy. The book begins with a lyrical momentby-moment description of a total solar eclipse, successfully capturing the beautiful natural occurrence in words. This is followed by a well-illustrated chapter providing clear scientific explanation of the celestial mechanics
6
of a solar eclipse. Readers who have a historical interest can find themselves immersed into the mythology of how ancient civilisations have accounted for eclipses as well as the description of heritages, such as Stonehenge, that testify to people's effort in predicting eclipses. Photographers who wish to take up the challenge of capturing a solar eclipse in film are sure to find Totality a helpful guide, enriched with technical skills and advice to eclipse photography, videotaping and image editing. This book demonstrates the scientific value of solar eclipses which have revealed many physical aspects of the sun normally invisible due to the strong light, one of which helped determine the solar atmosphere’s structure. Besides the mythology, science and astrodynamics of eclipses, the best feature of Totality is the practical guidelines of how and where to view an eclipse. This edition is updated with information on the total solar eclipse on 22 July 2009 and the predicted path, time and duration of the up-coming solar eclipses until 2060. If you intend to witness the total solar eclipse next year in India, China
and Japan, I highly recommend Totality to be included in your backpack. M. Littmann, F. Espenak and K. Wilcox,Totality: Eclipses of the Sun, OUP, 2008, £20 RRP
Kathryn Chung is an undergraduate student in Part II Genetics
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TECHNOLOGY
Paper Revolution Imagine yourself lying on a sunny beach in your favourite holiday destination.You want to relax with the latest newspaper headlines, but getting hold of a copy is sometimes tricky, and who wants to carry a thick stack of papers to the shore? “I guess I could bring my laptop,” you think, “but can I do better?” Many of us have wondered how great it would be to have a small sheet of paper that updates itself constantly with the latest news, at our own discretion. Too good to be true? Science-fiction lunacy? Not really. The answer is electronic paper, and the technology is already available.
“The future of electronic paper faces several challenges”
TOM WILKS
For over 5000 years, words and images have been passed around on paper. The advent of computers, while offering new possibilities cannot beat the portability, low cost, and readability of printed matter. Paper also has its limitations: once printed on it can’t be easily erased and it is inconvenient to carry more than a few papers or books around. By mixing the paper and the computer, electronic paper can offer the best of both worlds.
A locally applied current orientates the microcapsules to display an image on the Gyricon
Lent 2009
In 1974, Nick Sheridan, a scientist at the Xerox Palo Alto Research Centre, pioneered the Gyricon, the first technology to make electronic paper possible. Coming from the Greek for ‘rotating image’, the Gyricon consists of tiny beads able to rotate freely between two thin layers of transparent plastic. The beads, half black and half white, rotate according to an applied voltage and create an image. Despite this breakthrough, the idea was expensive and had poor resolution. Two decades later, the company E Ink demonstrated a new technology that offered better resolution, brightness, and was potentially cheaper: electronic ink. The ‘ink’ is composed of millions of tiny microcapsules. Each capsule is approximately the diameter of a human hair. Within each microcapsule there are positively charged white particles and negatively charged black particles, suspended in a clear fluid. When a negative electric field is applied from above, the white particles rise, giving a white appearance to the microcapsule. Simultaneously, a positive field is applied from below, attracting the black particles out of view. An entire page is made up of tiny pixels, with one microcapsule per pixel. By applying the correct localised electric fields, the particles in the microcapsules are moved up and down, allowing the page to show the desired patterns of black and white. The ink can coat various surfaces, such as plastic and metal to make flexible, lightweight and even foldable displays. The electronic display is very energy efficient as power is required only to change the displayed image; the image is fixed otherwise, and can be read without back-lighting, in both dim light and full sunlight, making it a fine replacement for
PLASTIC LOGIC
Fernando Ramos discusses the technology behind electronic ink
Cambridge spin-off company, Plastic Logic’s new electronic reader uses E Ink technology to display images.
printed newspapers, technical documents, and even books. By considering the power and trees it saves, this is a truely environment-friendly technology. The future of electronic paper faces several challenges. Colour displays come to mind – hitherto attempts to add colour are far from perfect. The low refresh rate of the ink is another drawback, making the technology unsuitable for displaying animation or video. More advanced electronics are also needed to obtain higher degrees of flexibility, resolution, and a lower cost to
“The electronic display is very energy efficient”
bring it even closer to real paper. Despite the obvious advantages, it might not be easy to leave paper for its electronic counterpart. Paper has been around for over five millennia. Electronic paper does look like a promising contender in changing the way we read and write. Are we on the eve of a second print revolution, after Gutenberg’s press? Fernando Ramos is a PhD student in the Department of Engineering and in the Computer Laboratory 7 07
SITA DINANAUTH
A Colourful World Katherine Thomas looks at the vibrant properties of iridescence Imagine a SOAP bubble. At first glance, the film appears to be transparent, yet if you look more closely you can see that it is actually very colourful.The vibrant colours change as the film fluctuates and the observation angle changes.The phenomenon producing this colour is iridescence. Unlike colour produced by pigments and dyes (see Pigments and Dyes), the colour comes entirely from the structure on the object’s surface. Iridescence is a result of interfering light waves. The colour of our soap bubble is determined by the thickness of the film. When light hits the film, some reflects from the outer surface, while some enters the film. Light that enters – transmitted light – is reflected back and forth between the inner and outer surfaces of the bubble, before reemerging. The colour observed results from interference of all these reflections. Each time the light traverses the film it undergoes a phase shift directly proportional to the thickness of the film and inversely proportional to the 8
wavelength of the light. This means that for a film of a given thickness constructive interference will occur for some wavelengths, while destructive interference will occur for others. While the hue observed is highly directional and depends on the film
“Iridescence is also a defence mechanism used to distract attacking birds” thickness and the angle from which it is observed, the vibrancy depends on structure as layers affect the amount of light that is bent, called the refractive index. The colours produced by the soap bubble are very transparent since the iridescence is produced by a single film. However, if one makes a stack of alternating material layers, tunes the thicknesses and maximises the refractive index contrast of these layers, brighter and more vivid colours can be created.
Nature has many examples of these multilayer iridescent structures. Peacocks, Japanese jewel beetles, hummingbirds and a number of butterflies and moths all produce their colour via structures on their wings and feathers rather than pigments. One extensively studied example of iridescence in nature is the wings of the Morpho butterflies, which inhabit Central and South America. Perhaps the most iridescent of the species is Morpho rhetenor. Stunning blue colours are seen on the dorsal side, or back, of the male wings, in striking contrast to the dull, dark brown ventral, or front, side of the male. The surface of the male’s wing is covered in a series of scales. A crosssection through one of these scales reveals intriguing complex structures, which look like long, thin, miniature Christmas trees. These structures effectively act like a multilayer of air and cuticle, maximising the contrast between the layers’ refractive indices and www.bluesci.org
thus producing the striking colours. But how do we know that this structure is what produces the colour? We know this structure produces the colour because it has one important property: as you change the viewing angle, the hue you observe should change. For a given material, the thickness of the layer will determine the colour; a thinner layer will look bluer, while a thicker layer will look redder. As you change the angle from which the structure is observed, you change the ‘effective’ thickness of the layers which changes the colour. This effect does not exist for colours caused by pigments. The Morpho rhetenor wing is bright blue when seen from directly above. However, from other viewpoints it appears violet or dark blue. If you immerse the wing in a liquid such as acetone, the solvent floods the spaces between the scale’s microstructures. Now, instead of air and cuticle, we have alternating layers of acetone and cuticle. The thickness of the layers has not changed, only the contrast between them. The wing now appears green instead of blue and the colour is less vibrant. Submerge the wings in a liquid with the same refractive index as the cuticle and the back of the wing now appears the same brown colour as the front. The multilayered structure has been effectively hidden and only the pigmented colour of the wings is observed, reinforcing the structural origin of the blue colour. Morpho butterflies are known to be highly territorial, attacking any rivals. The shiny fluttering of the bright blue wings makes them easy to see over large
WOODY THROWER
FEATURES
Photograph showing the colours formed by the interaction of light with a water-oil mixture
“Colour is life; for a world without colours appears to us as dead...As flame begets light, so light engenders colours. Colours are the children of light, and light is their mother. Light, that first phenomenon of the world, reveals to us the spirit and living soul of the world through colours.” Johannes Itten (1888-1967) distances. Any male encroaching on another’s territory is easily spotted and chased away. Iridescence is also a potential defence mechanism for butterflies used to distract attacking birds. The constant flashing of colour as the butterfly flaps its wings confuses the predator, allowing the butterfly chance to escape. Iridescence is also thought to play a role in mating. Although this is not really seen in the butterflies, peacocks and birds of paradise do make use of this. Male peacocks attract the attention of females via the brightly coloured
Pigments and Dyes There are many ways to produce colour, however, they all require one thing: the presence of light. Visible light can be seen as waves of energy with wavelengths of 380-760 nm, each wavelength appearing to us as a different colour. When light interacts with an object, it can be scattered, reflected, absorbed, refracted, diffracted and it can also interfere with other rays of light. These processes produce the colourful world we see around us. Our clothes, hair and skin contain pigments or dyes. These are chemical complexes which selectively absorb and reflect different wavelengths of light. The wavelengths reflected determine the colours that we see. However, objects containing pigments are often lacklustre and monotonous, unlike those that are iridescent. Lent 2009
eyespots on their tail feathers. Males with the brightest, most iridescent feathers are visited more frequently by potential mates and are more likely to have a successful courtship. Iridescence is not only important in nature; it also plays a role in our everyday lives, from colourful fabrics that shimmer as you move, to road signs that are easier to see. Flakes of iridescent colours are added to car coatings to make them bright and gleaming, while smaller flakes are put into hairsprays, which glisten and shine. Anti-forgery marks on money and passports also use these structural colours because they are so hard to recreate. Iridescence is a fascinating phenomenon that can be used to produce vibrant, well-defined colours. In nature, many creatures rely on these colours to survive and reproduce. Who would have thought that the simple laws of reflection, refraction and the interference of light could play such a pivotal role in life from bugs to the birds and the bees? Katherine Thomas is a PhD student in the Department of Physics
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VIVEK CHUGH
More than a flight of fancy Matt Child explains the role of birds in our ecosystems My business-oriented friends often sarcastically question the point of ornithology. They do this largely to annoy me, partially to make themselves feel better about the shallow, commercially driven existences they lead, but mostly because they genuinely do not understand the key functions that birds perform in ecosystems. Shockingly, we as a species are very much dependent upon these ecosystems. Birds are both numerous, with over 10,000 species worldwide, and widespread, making them invaluable mobile links in ecosystems. In a recent scientific paper, Stanford University researcher Cagan Sekercioglu outlined three ways in which birds link different parts of an ecosystem. They were defined as genetic, resource and trophic roles. These linking processes are vital cogs in the mechanics of ecosystems across the globe.
“The droppings and carcasses provide a crucial input of nutrients ” The most well-known link is between birds and plants. The seemingly simple, flower-probing action of a hummingbird allows the isolated male and female plants an opportunity to reproduce. This mediated mixing of genes maintains the genetic diversity of plants, which 10
aids species in adapting to changing environments. Adaptive capacity is particularly important as humans continue to modify landscapes rapidly and unpredictably. The pollination services of birds are important in both natural and crop ecosystems. Birds also structure ecosystems through seed-dispersal. More plant species are able to survive when birds transport seeds away from seed predators and resource competitors into distant habitats. This increases the overall species diversity of a region and allows new ecosystems to ‘nucleate’ when these transported seeds grow and mature. Some birds, such as the Eurasian jay, can carry seeds up to 20 km in one trip. Birds behaving as seedling couriers can increase the dispersal rate of plants into fertile lands. Without this crucial service, immobile plants would be doomed to extinction in isolated, resource-poor patches. Seed-dispersal services will become increasingly important in the coming decades as plant species are forced to track rapidly changing climates across cluttered and inhospitable landscapes. Birds also perform what’s called ‘resource linking’. Some landscapes are dominated by nutrient poor soils whilst some have been mismanaged to the point where most of the fertile topsoil has been lost. In these cases birds can introduce external nutrients from other
areas of the landscape or from completely separate ecosystems. Along coastlines, the droppings and carcasses from seabird colonies provide a crucial input of nutrients to nearby habitats on land. Seabirds act as resource bridges between the vast, sombre stretches of the ocean and the scraggly, struggling plant and
“Birds act as conduits for the flow of genetic information” animal communities on the coast. This is nothing to shrug off. Researchers studying the Aleutian Islands ecology in Alaska found that introduced arctic foxes caused a drop in seabird numbers. The population crash led to critical reductions in soil phosphorous and nitrogen, causing an irreversible shift from grassland to semi-arid tundra on the islands. Seabirds, it seems, were responsible for sustaining the entire shoreline ecosystem. That’s pretty good going by most standards. There would also be hefty consequences for terrestrial ecosystems if birds were to disappear. Not only would ecosystems be adversely affected but economic prosperity as well. Researchers have estimated that insect-eating bird species can save around $1210 per square kilometre per year by preventing insect www.bluesci.org
pest outbreaks. Similarly, birds of prey can reduce rodent pest populations either directly or indirectly through what researchers have coined the ‘landscape of fear’. The perceived risk of predation by big, talon-wielding birdies can discourage little, lettuce-feeding bunnies
“Birds introduce nutrients from other areas or from completely separate ecosystems”
MATT CHILD
from setting paw into an open pasture. The rabbit population then declines because, somewhat cruelly, the terror of potential death slows the foraging and thus breeding rate. Such enmity also stabilises and diversifies the ecosystem by ensuring no single prey species is allowed to dominate others. Birds are better pest controllers than their mammalian counterparts. Able to soar freely across the landscape, they respond quickly to transient pest outbreaks. The rapid response to sources of food is also the reason why some birds, most notably vultures, crows and ravens, are such successful recyclers for ecosystems. Importantly, recycling services both accelerate energy flows through the landscape and prevent disease outbreaks from rotting carrion, thereby helping to increase the quality of life for humans
living in nearby settlements. Finally, we reach the most indirect service our feathered friends provide: ‘ecosystem engineers’, a term used by ecologists to describe the ways in which species physically alter habitats. Birds such as woodpeckers create brandnew nesting sites out of otherwise inaccessible tree trunks. Woodpeckers’ abandoned nests are used secondarily by other bird species. These secondary species then go on to perform their own special functions. Birds may also act like earthworms and moles combined by excavating burrows that help till soils and simultaneously create ‘microclimates’ that aid the establishment of rare plant species. Birds directly alter the characteristics of their habitats, the ramifications of which ripple through the ecosystem as other species respond to these alterations. Yes, birds are pretty, but their purpose transcends the aesthetic satisfaction of bird-watchers. Avian functional attributes resonate deeply within ecosystems, across all levels of ecological organisation and through the epochs of evolutionary time since the dinosaurs. Birds act as conduits for the flow of genetic information between plant species, enhance the diversity of ecosystems, add vital nutrients into otherwise unproductive landscapes, remove damaging pests from sensitive agricultural systems and structure habitats through their actions.
MATT CHILD
FEATURES
What’s more, all this is only what we know birds can do. There are too few researchers and too many birds to be capable of fully comprehending avian impacts on ecosystems. Ornithology is an exciting frontier across which disciplines such as ecology and economics can be combined to empirically evaluate the cost of losing certain bird species. Intuitively, one feels that ‘cost’ is an unjust term in that the loss of a single species is priceless in its own right. But armed with the knowledge that birds truly do add more to the world than a mere splash of colour, we can all go forth and defiantly declare to our bird detractors that ornithology is not simply the study of vague and unimportant creatures, but of the creatures that help create and sustain ecosystems. Those very same ecosystems, incidentally, that we self-indulgently drain. Matt Child is a PhD student in the Department of Zoology
Lent 2009
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EQUINOX GRAPHICS
Just Empty Space? Lara Sibley unravels the extraordinary properties of a vacuum The nature of vacuums has puzzled physicists for centuries. In the absence of matter, what exactly makes up empty space? Can it be considered as a fundamental frame of reference, a constant background through which particles move? Understanding the properties of a vacuum has been the key to understanding diverse phenomena from geckos’ feet to the limits of nanotechnology, but its properties were once less well understood.
“The Casimir force may even enable objects to levitate” At the start of the 20th century, vacuums were thought to be composed of a mysterious substance known as the ether through which light was thought to travel. Light was believed to be a wave and therefore carried by some kind of substance, just as sound 12
waves are carried by the air. In 1887, Michelson and Morley performed a series of experiments designed to detect the ether by measuring the difference in the speed of light beams travelling with and against the motion of the Earth. These experiments failed to detect a difference and the debate about the nature of the vacuum, and light itself, raged on. At the turn of the century, Einstein challenged two of the fundamental concepts of physics. First, he showed that the speed of light is the same for all observers, regardless of their velocity. This means that there is no special stationary frame of reference; rather every non-accelerating observer is equivalent. Second, he showed that light is not just a wave, but also a particle. Unlike waves, particles can propagate without a medium. The need for the ether was gone, but what would replace it? Could a vacuum be empty? These questions were about to be answered by the development of
another revolutionary theory of physics: quantum mechanics. Here, a vacuum is the state with lowest energy; that which contains no particles, the zero state. This absence of particles and fields would be
“The creation and annihilation of particles make a vacuum far from empty” uninteresting were it not for one detail. In this state, there is a small possibility for particles to be spontaneously created and then quickly annihilated. A quantum particle exists as a combination of all its possible states. If it is possible to create or destroy a particle, no matter how small the probability of it happening, there will be a tangible effect. The creation and annihilation of particles actually makes a vacuum far from empty and instead filled with short-lived particles. www.bluesci.org
Creating particles with mass requires a great deal of energy but the creation of massless photons has a far more significant effect. Photons are particles of light, but they also propagate the electromagnetic field. When a photon is destroyed, it jumps into the zero state, and when it is created it jumps out of it. As there is no limit to the number of photons being destroyed and created, the zero state can be considered to contain an infinite number of photons.
“The idea that a vacuum has an energy is a startling result of quantum mechanics”
OSKAR GELLERBRANT
These quantum fluctuations, as the creation and destruction of short-lived particles are known, give a vacuum finite ‘zero point’ energy. The idea that a vacuum has an energy is a startling result of quantum mechanics. The short-lived photons can have a surprising effect on objects separated by a very small distance. Imagine two conducting parallel plates. Photons created outside the plates will push them together, whereas those created inside will push the plates apart. The wave-like nature of light means that only photons with certain wavelengths will be allowed within the plates. More are created outside, pushing the plates together. This force is known as the Casimir force, named after Hendrik Casimir who proposed the effect in 1948. This remarkable force causes objects with very small separations between them to collapse together and
10µm The setae on the foot of a gecko seen with a scanning electron microscope
Lent 2009
permanently stick, an effect that can be seen in nature. It is this that enables geckos to stick to walls. Geckos’ feet are covered in tens of thousands of setae, tiny hair-like structures which in turn are covered in hundreds of spatulae. These spatulae are smaller than the wavelength of visible light and so experience a Van der Waals force (a microscopic version of the Casimir force), which causes them to stick to surfaces. The force is so strong that geckos evolved with a way of removing their feet from the wall; only possible by peeling them inwards from their toes. We can only observe the Casimir force between objects with separation comparable to the wavelength of light – an extremely difficult technological challenge. With the advent of nanotechnology, the observation of the Casimir force in a laboratory became a reality, and was first measured in 1997, between a flat plate and a hemisphere. However, as electrical devices become smaller the Casimir force has started to cause problems. Microelectromechanical systems are widely used devices that contain structures fabricated onto a silicon wafer. Currently, they are large enough to be described by classical physics. As miniaturisation continues, the rules of quantum mechanics start to apply, and the Casimir force causes structures to collapse and permanently stick to nearby surfaces. Scientist may be able to overcome this attraction by designing the device so that the Casimir force becomes repulsive. One way of reversing the force is to use materials that have a large response to magnetic fields. The Casimir force may even enable objects to levitate, by making the force between an object and surface repulsive instead of attractive. Research in St Andrews University has revealed that the Casimir force can be reversed by inserting a left handed material between the two plates. A left-handed material is one which is negatively refracting; it bends light the opposite way to normal materials. Ulf Leonhardt, professor of theoretical physics at St Andrews University, describes the principle behind his work: “We found out that a negatively refracting
IAN FYFE
FEATURES
Only light waves which fit whole numbers of wavelengths between the plates are allowed, meaning that there are more photons allowed outside the plates.
medium performs a coordinate transformation. It creates the illusion that one coordinate axis is running backwards. Now, in the transformed space the Casimir force is the usual attractive one. Attraction would reduce the distance between the plates, but if the transformed space is running backwards, the distance increases in physical space; attraction is turned into repulsion.” This idea could allow materials to be levitated on nothing.
“This force causes objects with very small separations to collapse together and permanently stick” That a vacuum is not empty space, but an endless supply of short lived photons is one of the most surprising results of the theory of quantum mechanics. The Casimir force is becoming more and more important as technology reaches the nano scale, and the creation of novel ways of utilising the Casimir force is a vital goal of modern physics.
Lara Sibley is a PhD student in the Department of Physics
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ADAM MOUGHTON
Moira Smith looks at new developments in the fight against cancer UltrasoUnd is remarkably versatile; dolphins and whales use it to communicate and bats use it to navigate at night. Humans most famously use it to image foetuses during pregnancy. However, the power of ultrasound was known years before imaging was invented and recent research has highlighted its use in the treatment of cancer. as early as 1927, friends Wood and loomis showed that high-frequency sound waves could kill cells deep within the body. a year previously alfred lee loomis, a millionaire investment banker, inventor and gifted mathematician, had renewed his acquaintance with robert Wood, professor at Johns Hopkins University. loomis was so enthused by the potential of ultrasound that he equipped an elaborate laboratory in an old mansion where they worked together investigating the biological effects of ultrasound.
“Ultrasound therapy was ahead of its time” Much of the early research was focussed on preventing the destructive power of ultrasound. However, it was eventually recognised that its tissue-damaging power could be used beneficially to destroy cancer. the first 14
successful ultrasound treatment was performed on a skin tumour in 1944. despite this success, ultrasound treatment became unfashionable within the academic community for several decades. a conference in Erlangen, Germany, in 1944, concluded that the potential of ultrasound was not backed up by clinical results and therefore “should be discontinued”. Ultrasound therapy was ahead of its time: to realise the full potential of ultrasound further developments in imaging were required. decades passed before imaging was sufficiently advanced to be able to prove the powerful and accurate non-invasive effects that ultrasound could achieve. improvements in imaging and the increase in funding for novel medical techniques in the past few years have seen an explosion of research into ultrasound applications. Professor Gail ter Haar of the institute of Cancer research, surrey, has led the field of high intensity focussed ultrasound (HiFU) research, and produced many successful clinical studies. in an article she wrote: “it seems clear that HiFU is finding useful clinical roles, although its application (and technical development) is still in its infancy. the potential to destroy a cellular volume to an accuracy of only a few cells, while leaving surrounding tissue unaffected, has considerable appeal.”
High power ultrasound is surprisingly versatile and can also be used to aid treatments ranging from physiotherapy to gene therapy. specific applications include destroying kidney stones, improving drug uptake into cells, halting major bleeding and dissolving blood clots in stroke victims.
“Ultrasound can generate enough heat to burn cancer cells to death” the advantage of ultrasound is that it is non-invasive; it is a pressure wave so is able to travel directly through the human body. the procedures listed can be performed externally with minimal preparation, massively reducing the risk of infection for patients. Ultrasound’s curative power depends on its ability to influence tiny air bubbles inside human cells. When a sufficiently energetic wave hits a bubble, the bubble collapses, heating the surrounding fluid and generating high pressures. Ultrasound-induced bubble collapse can generate enough heat to burn cancer cells to death and accurately focussed waves can destroy tumour cells without damaging the surrounding healthy tissue. Ultrasound devices already have regulatory approval and are in clinical use www.bluesci.org
against cancer. One device, the Sonablate 500, has been designed to attack prostate cancer yet preserve the patient’s erectile function that can be lost during surgery. Other companies are scrambling to obtain licences for their own devices. However, further research is still required as ultrasound therapy faces two main challenges: imaging and breathing. Imaging the tumour accurately is essential to prevent damage to the surrounding healthy tissue and to assess the treatment’s success. However, the patient’s breathing can disrupt the process. Breathing causes the tumour to move back and forth, requiring real-time imaging to target the tumour accurately. Progress has been made in developing software for this purpose but it is still difficult to capture images quickly enough to accurately track the tumour’s motion. Professor ter Haar outlined the problems in 2001: “To achieve the utmost precision in cell killing, it will be necessary to develop better methods for targeting the beam’s focus and for monitoring the ultrasonically induced tissue destruction in real time.” Magnetic particles may be the solution to the breathing and imaging problems. Researchers at the University of Cambridge have developed a nanoscale magnetic particle that can be held stationary within the blood flow. These magnetic particles are less than a millionth of a millimetre in width and are made from oxides of iron called magnetite (Fe3O4).
“The advantage of ultrasound is that it is non-invasive” Cancers often contain many blood vessels, so tumours will readily accommodate these blood-borne particles. The motion of these tiny particles can be controlled using a magnetic field created outside the patient’s body. Once the magnetic particles have been injected into the bloodstream, they flow through the blood vessels until they reach the tumour. Using external magnets, Lent 2009
JAMIE MARLAND
FEATURES
The response of nano-magnetic particles to focused ultrasound can be studied in the lab
these particles can be held stationary, or even moved within the tumour by manipulating the magnetic field. The technology for producing strong magnets that can be finely adjusted is well established and already used in hospitals worldwide for imaging. The particles show up brightly on scans so facilitate tumour imaging. The magnetic particles would also help to destroy the cancer by dramatically increasing the heating effects of ultrasound. They provide a surface on which bubble formation and collapse occur more readily. More bubbles means hotter temperatures and if the ultrasound is just below the threshold pressure needed to collapse bubbles, it will not damage tissues unless the magnetic particles are also present. Combining ultrasound and magnets is still in its infancy, but shows enormous promise as all the components are already in clinical use and known to be safe. Dr Nicholas Darton of the Department of Chemical Engineering and Biotechnology said “The technology we are now developing can
be used to move drug-linked magnetic nanoparticles to tumours using magnetic fields. When this approach is combined with focussed ultrasound it will offer a promising new therapeutic strategy for accurately targeting and eliminating tumours without affecting healthy tissue.” Ultrasound is extremely attractive as a cancer treatment because it offers patients fast, accurate, scar-free and painless treatment. Combining ultrasound with magnetic particles can significantly improve tumour tracking and imaging, and thus the accuracy and efficacy of treatments. Ultrasound devices are already achieving great success in the clinical treatment of cancer. As our understanding of these combined techniques develops and the various regulatory hurdles are overcome, the dream of a fast and painless cure for cancer will come closer to being reality. Moira Smith is a PhD Student in the Department of Chemical Engineering and Biotechnology 15
SUPERHUMAN... Evolution is unaware of progress. there is no ladder, no pinnacle, no goal. As Richard Dawkins fervently put it: “the language of purpose can mislead…you will find that the purpose of life certainly has nothing to do with the survival of the species.” Evolution’s key processes – reproduction, variation, natural selection - are not conscious programs striving for perfection. novel characteristics or traits appear through essentially random mechanisms and are only as favourable as their ability to adequately allow organisms to deal with current challenges. the constant flux of our environment causes organisms to frequently face new challenges. Humans have mastered their landscape, mined the Earth for resources, farmed for food, mapped the globe – and in the process irreversibly changed our environment. Although still tied by the same evolutionary mechanisms, we have been graced with the ability to intervene. science and technology have given us the power to take back some control. Can we cheat the system? Engineer our destiny and beat the random process? this issue, FoCus looks into designing our future.
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FOCUS
...in pursuit of perfection
BILL BRANSON
Lent 2009
we breed, the crops we grow and our own genetic faults. Some hereditary diseases can potentially be eliminated through gene therapy, the technique of deleting and replacing defective genes. Gene therapy in humans has so far focused on rare immunodeficiency diseases but it can also be applied to acquired neurodegenerative diseases and
“Humans learnt to survive with more than what nature provided” cancer. Clinical trials for gene therapy are ongoing with the uK conducting 12% of all trials globally. Carriers of hereditary genetic diseases can already have their embryos screened. Pre-implantation diagnosis currently tests
LINDA BARTLETT
The journey from primordial soup to primatial sophistication took approximately 3.5 billion years. Through random mutations, organisms changed. useful traits boosted an organism’s chance of survival and through reproduction were passed onto the next generation. organisms grew increasingly complex and adapted to changing terrain and environments. Homo sapiens, the modern human we recognise today, developed about 150,00-100,000 years ago. humans learnt to shape their environment and survive with more than what nature provided. Culture, language, technology and science have marked us out as a species, far removed from our early ancestors and the other organisms inhabiting the planet. Whilst other animals struggle with the traits they were born with, humans have an almost limitless power in technology. For many, survival is almost guaranteed. The basic essentials of food, water and shelter are plentiful. Disease is understood and can be cured or eradicated. even faulty organs can be replaced. our understanding of the genes that shape us exploded in the last century to the extent that we now have the capacity to change them. We can alter the animals
GREG KNOBLOCH
BlueSci looks into designing our future
for over 200 genetic diseases covering many of the sex-linked disorders, single gene defects or chromosomal disorders. Defective embryos are discarded and parents can be safe in the knowledge that they will not pass on these disorders to their children. Such thoughts are comforting.We have gained some control over our genetic heritage. But if the genes for characteristics such as intelligence, strength and longevity can be identified, would we enhance our children? Give them an upper-hand? embryonic and pre-implantation diagnosis quickly turns to talk of sexselection and the prospect of designer babies. While ambitious parents may do anything to provide a head start in life for their children, the parental aversion to harming their child would probably rein in their aspirations. even if the tight regulations were lifted, the risks involved mean that it’s unlikely that people would start queuing in large numbers to have their child tinkered with by scientists. While we’re still hesitant to manipulate our food crops, it’s unlikely we’d want to do the same to our children. If we were to exhibit such genetic control could we be sure of the outcomes? Genetically enhancing 17
an embryo is severely limited by the rarity of known single genes that have a consistent beneficial effect. The hereditary link of heart disease, type-II diabetes and some cancers are similarly unlikely to be caused by single genes. Individual genes can also produce multiple effects, known as pleiotropy, which further compounds the problem. Many genes are established through compromise; while men grow bigger and stronger than women, they live shorter lives, a seemingly necessary trade-off. The situation, where a gene can produce both beneficial and deleterious
effects, is known as ‘antagonistic pleiotropy’. one of the regulatory proteins, named p53, limits extensive cell
“Would eradicating all unwanted genes benefit the human race?” replication that can produce tumours. however, the cancer reducing properties might inadvertently accelerate ageing by affecting the stem cells required for the maintenance of healthy organs.
If we were to eradicate all unwanted genes, would this necessarily benefit the human race? Genes considered undesirable now may be of some benefit in the future. Thalassemia and sickle cell anaemia, for example, are both genetic blood disorders caused by recessive genes. A host carrying a double copy of the mutant gene will, respectively, suffer from improper haemoglobin proteins that provide poor oxygen supply or abnormally shaped red blood cells that restrict blood flow. however, healthy carriers, with just a single copy of either mutation have an increased or total
DUKE UNIVERSITY
An Intelligent Design
AS I WrITe this and you read it, we are both achieving a remarkable feat. A feat so amazing we don’t even think about doing it. These skills we learn from childhood are incredible. And though many argue that some animals show sparks of intelligence, humans are the only species to have such a wealth of finely honed skills such as the use of tools, language, problem solving, consciousness and theory of mind. As Professor Barry Keverne points out, we “uniquely possess an internal representation” of our actions, a trait which gives us control over what we do and why we do it.
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The reason we’re so clever is not really such a surprise; it’s right in front of our noses – or just behind, to be more precise - our big brains. Whilst our brains are certainly big in relation to our body size, the important factor is the human cortex. our prefrontal cortex is thicker and denser than that of any other animal. We have high nerve conduction speeds and keep distances short which gives our brain an unrivalled information processing capacity. Intelligence is not determined by one discrete area in the brain. rather, it seems that there are lots of important regions throughout the brain; and the
more connections between them, the greater our cognitive potential. Since the time of our first walking ancestors, brain size has tripled. The most rapid expansion of the brain of the Homo genus happened 500-100 thousand years ago. Development of culture and larger social groups are responsible for this, requiring language and the use of tools, which both need a larger brain. These characteristics were beneficial to early humans, allowing them more flexibility and better strategies to cope with the environmental elements and group living. The advantages this gave us acted as a positive feedback to progressively produce larger brains, a fact confirmed by genetic evidence of the genes Microcephalin and ASPM. These genes may have been subject to positive selection over the time that humans have developed culture, possibly showing that bigger brains themselves have also been under positive selection. If big brains are so great, why aren’t ours the size of houses? The main downside of our brains is that, even
though they account for only 2% of our body weight, they use a quarter of our daily calories. This leaves less energy for other organs and is probably the reason that humans have reduced the size of their intestine. Another problem of a large brain and skull arises during childbirth. humans have resorted to giving birth early, before the brain and skull are fully grown (our brain keeps growing until we reach the age of seven). Mothers have to care for their children for longer periods complicating and possibly limiting the number of offspring they have during their lifetime. In our more recent history, brain size has remained fairly constant because of the physical constraints the brain places on the body. Whilst they are unlikely to grow much bigger, our brains could definitely get better and more efficient, further increasing intelligence. Drugs and artificial intelligence could further increase our abilities. We think our brains are amazing now, just wait for the future…. Rachel Swain
www.bluesci.org
BILL BRANSON
resistance to malaria, and a selective advantage over their peers. The advantage is only relevant in endemic malaria regions. elsewhere, prospective parents carrying the mutation may opt to screen their embryos and prevent this gene being passed on to their children so they don’t develop the disease. even without genetically altering our make-up, the human race is doing pretty well. In the last 200 years, life expectancy has doubled in the West as medical and surgical advancements have allowed us to live longer and healthier lives. on 3 March 1967, Louis Washkansky was the recipient of the first humanto-human heart transplant. he lived for 18 days after the operation before succumbing to pneumonia, a feat unimaginable at the turn of the last century. This operation is now fairly common and has high success rates. Thousands of babies are born every year with heart defects, often hereditary,
Vials of highly toxic chemotherapy drugs. Treatments using gene therapy could prevent their use.
drugs, such as Viagra and ritalin boost our stamina and concentration. Such things have become a part of life and we easily forget about the risks and the unwanted consequences of poorly understood drugs. The side effects of anabolic steroids have been well documented. The testosterone-based drugs boost performance, endurance and recovery levels but long-term use can cause physical changes such as breast tissue formation in men and increased body hair in women. When screening for steroids became possible, the drugs were banned, preventing professional athletes from using them. But as drugs are developed with minimal side effects, we must ask who is entitled to use these drugs. In December of last year, cognitiveenhancing drugs such as ritalin received mass media attention after a commentary in Nature suggested that healthy adults should take the drug, while a survey revealed that large numbers of students
“In the last 200 years, life expectancy has doubled in the West”
Lent 2009
BILL BRANSON
TIM TRUMBLE, ARIZONA STATE UNIVERSITY
but through heart transplants, surgery or medication, these problems are routinely treated. Similarly, those afflicted with type-I diabetes or kidney disease occurring in infancy would have died a hundred years ago but these children now live on into retirement and have families of their own. Science and technology have given the gift of life to many and have considerably improved our quality of life. Cosmetic surgery is already an option to make us look younger and correct our perceived imperfections. These
were already taking it. ritalin is used to treat attention deficit hyperactivity disorder in children but in adults, or those without this disorder, it boosts concentration, focus and memory with minimal side effects. Beta blockers are a class of drug most associated with treating high blood pressure. The drug works by blocking the transmission of the sympathetic nerve impulses. The effect is to stop your heart racing, prevent your palms and forehead from sweating and your face from going red. These are sought-after side effects for performers, politicians or anyone else who needs to hide their nerves or deception. But is it appropriate to take these drugs rather than develop the skills needed to overcome these effects? The rules of sport try to ensure a level playing field so that no competitor has an unfair advantage. As well as drugs, technology has begun to play a role. oscar Pistorius, the South African double leg amputee sprinter, was allowed to compete against able-bodied athletes last year despite claims that his carbon fibre artificial limbs gave him an advantage. Swimmers wearing Speedo’s new LZr racer swimsuit broke 62 world records when it was introduced last year, notably at the Beijing olympics. not wearing one was a considerable disadvantage. however, those with sponsorship deals with other companies had a difficult decision to make. 19
Performance enhancing drugs and technologies provide endless possibilities. Breaking a sporting record on drugs or through other enhancement
“Is there anything wrong with wanting to perform better? methods is certainly unfair if the same means aren’t universally available. But does this diminish the achievement? Maybe we should now consider a redefinition of achievement.
The more an athlete relies on drugs or genetic enhancement or surgical improvement, the less of the achievement is actually theirs. Without their doctor, their surgeon, their chemist, their goal would have been unachievable. The possibilities of physical, genetic and mental enhancement are very real but drastic changes are just beyond our grasp. The unknowns and the risks prevent everyone from embracing the new technologies. humans have indeed come a long way during our evolutionary history. But can we realistically improve upon what nature bestowed? or, in our attempts at perfection, will we upset the
delicate balance and introduce further inequalities into the world? humans can influence their evolutionary future, but, given the risks, most of us would probably prefer fate to decide and stick to the superficial changes that technology can provide. Katherine Thomas is a PhD student in the Department of Physics Lindsey Nield is a PhD student in the Department of Physics Djuke Veilduis is a postdoc in the Department of Biological Anthropology
The Science of the Superhuman
BABAK PARVIZ, UNIVERSITY OF WASHINGTON
TeChnoLoGy Borne out of necessity is starting to be abused for selfimprovement. For medical purposes, the development of artificial body components is essential, but for many the desire for better-looking, stronger and faster bodies is reason enough for surgery. For example, there’s a routine ulnar collateral ligament reconstruction operation that
some baseball players undergo, without being injured, in the belief that it increases their pitching speed. Surgery and cosmetic alterations aside, there has been a host of developments and potential applications to enhance the human body. Many are the subject of on-going research. Super-strength: In 1998 h. Lee Sweeney and colleagues at the university
of Pennsylvania injected mice with a recombinant virus directing over-expression of an insulin-like growth factor in muscle fibres. This led to an average of 15% increase in muscle mass and 14% increase in strength! This has practical implications for the treatment of genetic disorders or age-related loss of skeletal muscle. But the treatment could also be used to increase the strength of a normal individual. Maybe not as good as Popeye’s spinach, but certainly an improvement. Super-flexibility: In 1934 Karl Meyer discovered a strange substance in cow eyeballs called hyaluronan that helped cow eyeballs to keep their shape. The chemical can also act as a lubricant when injected into joints. Dr endre Balazs showed that it could be used in the treatment of arthritis. Today it is used to improve flexibility in athletes, to prevent post-surgery scarring and the appearance of facial wrinkles. Super-vision: Laser Contact lens developed by engineers at the University of Washington. surgery already corrects for The lens is flexible and biologically safe with an imprinted electronic the discrepancy from perfect circuit and lights. This technology could be used for mid-air virtual vision, but could we enhance display screen that only the wearer would be able to see. our vision? The fabrication
of biologically inspired eyes is in its infancy and treatments are mainly designed for those with existing vision problems. nevertheless, the development of artificial human vision requires only four main components: a camera, an image processor, a transmitter/receiver inside the body and a stimulator to produce electrical activity in the brain. New body parts: Face transplants, hand transplants, replacement kidneys and livers; some of these are routine operations but the shortage of donated organs has always been a problem. In 1937 russian scientists implanted the first totally artificial heart in the chest of a dog. The longest recorded survival with such a device is 620 days, with the major obstacles being bleeding, infection and blood clotting. It’s fascinating to imagine the possibilities that are open to us. But as possibilities grow, so do technology and the imagination. just where will it end? Djuke Veldhuis TITLE IMAGE: SONIA AGUERA
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www.srcf.ucam.org/cuer/
UNDERGRADUATE
Going Solar: Cambridge University takes on the solar car challenge In October, a team of Cambridge students will travel to Australia to compete in the World Solar Challenge. Their aim: to cross the country from north to south using the energy from the Sun. Cambridge University Eco-Racing (CUER) began in 2007 with the aim of designing a car to compete in the challenge. The core design work is done by fourth year undergraduates as a part of their final year research project. Last year’s team has already built ‘Affinity’, a prototype vehicle which was the first solar powered car to drive legally in the UK. Lucy Fielding is working on the aerodynamic design of the vehicle. She is trying to reduce the aerodynamic drag while still ensuring that it is safe to drive. One of the major problems that Lucy must consider the likelihood of a cross wind which could flip the car if it is poorly designed. During the summer she spent time gathering data from
Are Algae the Answer?
ANNA STEPHENSON
Algae is fast becoming the preferred source for biodiesel. Soaring food
An algae fermenter
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wind tunnel experiments on Affinity. She obtained flow visualisation images and took drag and lift measurements. She plans to verify these results using computational fluid dynamics to optimise the design. Apart from his role as team manager, Anthony Law is designing strategy software for his fourth year project. His role is to design software which will help the team to plan their tactics and strategy as the race proceeds. “It is a race of endurance,” says Anthony. “The aim is to optimise the speed of the car over the duration of the race by taking into
account the weather, traffic, route and real-time data from the car.” Once the car has been built, it is up to the strategy team during the race to maximise its potential and push it to the limits. So far, he has developed a simulator where users can take the car for a virtual drive to maximise the average speed over the duration of the race. Anthony and Lucy are excited and optimistic about the race. The Cambridge team is aiming high. “If all goes well, we hope to finish in the top ten next year, and to win the race the year after that,” says Anthony. TB
prices have questioned the use of food crops to produce biofuel, making algae an attractive alternative. The yield of biodiesel per hectare is far greater for algae compared to crops, with algae requiring around one thirtieth of the land to produce the same amount of fuel. Algae can be grown in infertile regions so does not compete with food crops for arable land as do other sources such as rapeseed. Furthermore, algae have a high growth rate, a naturally high oil content and make biodiesel that is non-toxic and biodegradable. The advantages are considerable. However, there are still technical hurdles which must be overcome. To obtain biodiesel from the algae, the cells must be broken down and the lipids extracted from these cells and processed. The oil extraction is expensive and most processes have only been achieved in the laboratory. The process is complex, consisting of
many stages and making it difficult to reproduce on an industrial scale. Two students from the Department of Chemical Engineering and Biotechnology at the University of Cambridge are currently undertaking research in this area. Matthew Gamage and Lewis Jones aim to reduce the cost of the process by investigating other reagents for the oil extraction. They hope to find a cheaper alternative to the currently used chloroform-methanol mixture, which will be able to achieve the extraction without a significant reduction in yield. “We are in the process of trying hexane, which is a promising option,” says Matthew, “since it is currently used for oil extraction from rapeseed and is relatively inexpensive.” They also aim to simplify the process in order to reduce the cost of mass production. If they succeed, in the near future, perhaps you and I may soon be filling our tanks with ‘Algaefuel’. TB 21
EQUINOX GRAPHICS
A Single Defective Gene Beth Ashbridge looks at the science and dehumanising effects of Huntington’s disease It takes a brave man to seek out his own fate, particularly when the outcome may be bleak. Charles Sabine is such a man. An Englishman who has built his career on the other side of the pond communicating some of the most horrendous acts of man seen over the past 25 years. He now faces his hardest challenge yet. Charles Sabine was a conflict journalist for the US-based National Broadcasting Corporation, reporting from Rwanda, Kosovo, Israel and Baghdad. His job was to bring the dark and hateful conditions of war to television screens. Despite seeing the results of war first hand, his most painful experiences to date have been the loss of his father and the deterioration of his brother – both as victims of the unyielding and incurable Huntington’s disease. Formally known as Huntington’s chorea, due to the jerky, uncontrollable movements typical of sufferers, a victim 22
of this degenerative neurological disease can expect a slow decline in cognitive and psychiatric abilities. Sufferers lose coordination, develop slurred speech or an inability to chew and swallow, and, as their brain function weakens further, they can become depressed, anxious and aggressive.
“No other experience instils more fear, dread and terror than this disease” Just over two years ago Charles made the difficult decision to get the genetic test that would tell him if he will develop the disease. “A simple test in a private London clinic and your entire world is turned upside down.” He had the faulty gene; a mutation on chromosome four containing too many CAG nucleotide repeat sequences. This
gene codes for the protein huntingtin, but the mutant version, generated as a consequence of having more than 27 of the CAG repeats, gains a novel function that disrupts the natural action of neurons in the brain. Unfortunately, while the defective gene is relatively rare, once it is acquired by one family member, this rogue gene can ripple through subsequent generations. As a witness to some of the cruellest and most shocking visions of war, Charles has tasted his fair share of danger. In 1996, he was captured in a region known as the Doboj pocket, in what was formerly Yugoslavia, by a platoon of renegade Mujahidin guerrillas. With an AK-47 held to his chest he was blindfolded and held in a room splattered with the blood of the previous, murdered hostages, while one of his captors pulled out the pin of a grenade and held it to his head: “But not that, nor any other [experience],” he www.bluesci.org
says, “instils more fear, dread and terror as this disease.” Huntington’s disease is rare, affecting around 5,000 people in the UK. Even Charles admits to never having heard of it until he was informed of his father’s diagnosis in 1994. Compared with dementia and Alzheimer’s that affect the lives of over 700,000 people, this disease receives little to no media coverage, despite the staggering cost to successive generations.
“It is one of the few diseases caused by a single dominant mutation”
EQUINOX GRAPHICS
Charles, who watched his father pass in such an undignified manner, knows that he and his brother are condemned to the same fate and is eager to publicise the disease. He describes it as a “dehumanisation” of its victim to the point where “any quality of life will drain away”. “The time-bomb is real, present and desperate with this gene” and he is conscious of it everyday. Will the next time he plays golf be his last? Will dropping that teacup mark the decline of his coordination? Will his friends, who promised to visit him “no matter what” still come when he can no longer talk? Most could not imagine having these questions plaguing every minute of every day, but Charles cannot escape them and neither can the 80,000 other sufferers across Europe.
The mutant gene disrupts the natural action of neurons in the brain
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Over the last few years, still presymptomatic, Charles has been travelling the world talking about his career and, uniquely, comparing the terrifying realities of war with his current reality – the inevitability of Huntington’s. Charles is the first to admit he is terrified every day of his life, particularly when he thinks about what his future holds. His aim is to raise the profile of the disease and eliminate the barriers of scientific communication so that research and knowledge are open and shared. He hopes that this can accelerate finding a cure. Dr Jenny MORTON and her research team in the University’s Department of Pharmacology have been studying the disease for nearly twenty years. The research takes two main approaches. First, they use transgenic mice carrying the mutation to try to unravel the relationship between the brain pathology and the symptoms. Then, they use the data from these pathological and behavioural studies to develop hypotheses about how to treat the symptoms of Huntington’s. “We showed recently that both HD [Huntington’s disease] mice and HD patients show abnormalities in sleepwake cycles,” she says. “When we treated the sleep abnormality in the mice with a drug called Alprazolam, we saw an improvement in cognitive function. We don’t know the mechanism underlying the improvement caused by the drug. However, since Alprazolam is already licensed for use in humans, the possibility exists that clinicians could now test this treatment as a way of improving cognitive function in HD patients.” Many have suggested that Huntington’s can act as a model for other neurological diseases. Dr Morton agrees with this wholeheartedly. “It is one of the few diseases caused by a single dominant mutation.…But we are discovering that even though it only affects one gene, the knock-on effects for other systems are very profound. Every year brings new and unexpected findings, many of which relate not only to this disease, but to other diseases as well. Importantly, Huntington’s
JENNY MORTON
FEATURES
Charles Sabine at his recent talk in Cambridge
turns out to be only one member of a whole new family of diseases caused by abnormally expanded CAG repeats.” Dr Morton started working on Huntington’s disease because of a chance meeting at a scientific conference twenty years ago. She sat next to a woman who told her how the disease had affected her husband’s family. Dr Morton recalls her story. “Neither she nor her husband knew anything about Huntington’s until his father developed the disease. Her husband then developed the disease. She now faced the prospect of spending the rest of her adult life nursing her children through the same fatal illness.” Moved by this story, Dr Morton looked up the disease when she returned to Cambridge and became intrigued by a very interesting scientific challenge that she has taken up ever since. To date, there is no cure for this devastating disease. There are drugs on the market that aim to control some of the more severe symptoms, such as the chorea or depression, but all treatments can only prolong life; they cannot halt the deterioration or provide a cure. This is why the development of therapies such as those from Dr Morton’s research is so valuable and provides hope for sufferers like Charles Sabine. Listen to the interview at www.bluesci. org/sabine Beth Ashbridge is a PhD student in the Department of Chemistry 23
A DAY IN THE LIFE OF...
From London to Stockholm Chloe Stockford meets Simon Frantz, senior editor for nobelprize.org SIMON FRANTZ
How do you divide your time between London and Stockholm? Right now I spend three weeks a month in London in our office in Camden and one week in Stockholm. During the week in Stockholm, where our head office is, I tend to meet up with other members on the team. We have about 25 people working for us.
Frantz began his career researching the genetics of cardiovascular diseases before making the jump into science journalism. His career has included working freelance, as well as working for a health website and several years at Nature. What is nobelprize.org? Well, nobelprize.org is the official website of the Nobel Foundation, established about ten years ago to act as a digital archive for the Nobel prizes that have been awarded since 1901. The website contains official information about the prizes and the Nobel laureates as well as videos of lectures and presentations, information, and educational games. The content is there to inform people of all ages about the prizes and the stories behind them. What do you do on a daily basis? Is every day different? If I could narrow it down, I would say that I have two typical days. One is around the announcement of the Nobel prizes and the Nobel week where the laureates come to Stockholm to get the prizes. During those two weeks we tend to act more as a news information service.The other typical day is outside of the Nobel week when I’m creating educational content. 24
Are you ever itching to get back into the lab? Definitely. There’s a huge element of wistfully thinking, “Oh what would have happened if I had stayed in the lab?” I think most people who leave the lab for journalism will have that in the back of their mind. With journalism and writing, you’re still close to the science; you’re still talking to people; you’re still excited by the things that excited you in the lab. But you don’t get a chance to actively answer those questions which is the most challenging and stimulating part of working in the lab. I do from time to time get pangs, but it’s not enough to make me want to go back! Who have you most enjoyed interviewing for nobelprize.org? It’s hard to narrow it down to just one person. The last person that really impressed me was one of the 2007 economics laureates Roger Myerson. He was receiving the top accolade in his field and he had clearly spent decades providing great findings and changing the world in terms of economic sciences. He was with a few laureates. Somebody was talking about surface chemistry and how you had to visualise the chemical reactions on the surface, and he saw a way of applying that to the way people were interacting socially in Iraq. I thought that was amazing how perceptive he was to realise this, and he was saying: “I was thinking of that for years and years and it wasn’t until this
person said that....” And I thought that was wonderful. You interview science as well as literature, peace and economics laureates. Is it harder to interview a non-scientist? I don’t necessarily find it harder. With scientists, I think you have to speak their language – their technical language. It is much easier to interview say the head of the literature prize committee about an author because you can say, you know, what inspired you about the books? Asking someone to explain spontaneous symmetry breaking, which was the subject of last year’s physics prize, is somewhat more difficult. Have you come across any scandals since working for nobelprize.org? Scandals? No. Stories? Yes. But none I can use here! Are you going to elaborate? I can’t persuade you? Part of the reason there are relatively few stories is that the whole nomination process is secretive and the committees take a great deal of pride in that being the case. To put it another way, nobody wants to be the first person that breaks from that. For reasons of preserving integrity and preserving the Nobel prize brand. It tends to be quite a closed shop. You hear about the Nobel prize winners before the rest of the world. Are you ever tempted to leak the information? No, never! I don’t think it’s worth my career. Making myself unhireable is not an ambition of mine.
Chloe Stockford is a PhD student in the Department of Chemistry www.bluesci.org
AWAY FROM THE BENCH
Stories from CERN
CERN PRESS & MEDIA
there we were, in a lift whose ponderous 100-metre descent enticed our imagination of what awaited us: ATLAS. The lift doors opened to reveal a spectacle befitting a celebrity. Dozens of people were taking photographs; others were fixing the final details of what looked like a Star Wars spacecraft. Such was my first encounter with ATLAS, the enormous particle detector positioned at one point on the 27 km Large Hadron Collider. I’d spent a summer in Geneva as an intern and this was enough to spur me to do a PhD on the ATLAS experiment located at CERN, the world’s leading particle physics laboratory. CERN is not only home to the biggest physics experiment of our time but also a sociological one too with an 8,000-people work force, representing 80 nationalities. In such an intricate human collaboration, how are all these people able to interact and produce useful research? Establishing connections and collaborations between scientists has proved an impetus for technological innovations that don’t involve particle
CERN developed the Grid to allow processing power to be shared between computer centres around the world.
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physics. At a time when researchers struggled to share information with scientists working in different locations, Tim Berners-Lee, a scientist at CERN, invented the World Wide Web, earning his lab the enviable motto: “Where the Web was born.” The next-generation Web, the Grid, has since been developed to increase computer power and data storage using optical fibre links and highspeed internet to connect PCs around the world. All this will be much needed when the LHC begins operations and produces masses of data that will need to be analysed using complex computer programs. The Grid not only runs analysis but allows researchers to monitor experiments in real-time and access data as it appears even away from CERN. The Grid technology has moved beyond CERN and is being used for financial and climate modelling and even finding a cure for malaria. Yet another way to connect people working at CERN is with the EVO (Enabling Virtual Organizations) system, which enables researchers to virtually attend conferences and give talks either through a phone or the web. Research meetings take place every day at the CERN site and with EVO collaborators throughout the globe get the latest updates and receive plenty of feedback. However, one can foresee a downside of working in collaborations this big: the issue of competition. The glory that great physicists receive is palpable at CERN where the streets bare the names of those who made fundamental contributions to particle physics: Rue Einstein, Rue Abdus Salam, Rue Curie. During lunchtime, the popular ‘Restaurant-1’ is almost a room of candidates for the unnamed streets. Despite the collaborative nature of the work, there is competition. Indeed, of the four major experiments at CERN,
CERN PRESS & MEDIA
Tanya Sandoval looks past the search for the Higgs boson
The ATLAS (A Toroidal LHC ApparatuS) experiment detector at CERN.
two of them, ATLAS and CMS, are hunting for the same new physics. Subtle rivalry and jostling for power among some of the members of the collaboration can be detected at CERN.
“One can foresee a downside of collaborations this big” There is a certain competition to have their name associated with a discovery. This contradicts the fundamental idea of ‘collaboration’, but when Nobel prizes are at a stake, that’s how it gets. CERN is not only about the physics you know but also surviving the politics, the people and the pressure to succeed. With so much going on at CERN it is inevitable that great things will come out of this innovative environment. Whether this will be what the particle physicists are looking for is anyone’s guess. With the amount of activity going on at present, even while we wait for the LHC to be fixed, science can only benefit from the work being done there.
Tanya Sandoval is a PhD student in the Department of Physics 25
ARTS AND REVIEWS
That’s So Random Natalie Vokes explores the statistical concepts underlying randomness Statistical concepts are now so familiar that we don’t even realise when we encounter them. Thanks to the US presidential election I am now so comfortable with polls that I’d trust them with my life, and I suspect that for some of us words like ‘hierarchy’, ‘average’ and ‘error’ are so un-scary that they conjure up warm memories of sports commentaries rather than maths classes. But I wonder if our increased familiarity has led us to forget how strange some statistical concepts are? So for this issue’s Arts and Reviews column I decided to delve into a truly bizarre statistical concept that we invoke all the time: randomness.
“The confusions embedded in randomness reveal our affinity for deterministic explanations”
KELLY NEAVES
At first glance, randomness seems pretty straightforward. I think most of us have an intuitive sense that a random event is one that is unpredictable – there is no underlying order determining the outcome – and the statistical definition seems to coincide with our intuition. Put generally, randomness describes
equally likely events. When we flip a coin, for example, we cannot predict which side it will land on because each outcome is equally likely. Thus the outcome of a coin toss is considered to be random. This definition, however, misses a key complication. Events can in fact be unpredictable without being random: imagine a deterministic universe. Mathematician and astronomer PierreSimon Laplace thought our universe to be driven entirely by the laws of classical physics; when Napoleon asked him where God fitted into his system, Laplace famously replied: “I have no need of that hypothesis.” The Laplacean model of the universe would definitely not be random, since every event that ever has and ever will occur is the result of laws. Despite this we, as humans with cognitive limitations, might still find Laplace’s deterministic universe unpredictable. It would very likely be impossible for us to build a model that included every piece of information necessary – say the position of every single atom in our solar system – to predict what will happen on Earth. The complexity of the world would make it unpredictable despite its underlying order. Randomness is thus not that easy to understand, at least as a freestanding concept. Instead, randomness might
be said to describe all occurrences that cannot be explained. To see this, consider the behaviour of a cell.
“Randomness describes those features we do not yet fully understand” Generally we think of a cell as an ordered system. It contains certain key structures, like mitochondria and DNA, and engages in regular behaviour, such as DNA replication or energy production. The more we study the cell, the more we can describe its behaviour in terms of regular, causal interactions and the more we feel we understand biology. Randomness only enters our explanations to describe those features we do not yet fully understand. We often, for example, describe genetic mutations as random events. In doing so, we indicate that we cannot explain why they occur or when and where they do. Should it be that DNA mutations suddenly became explicable, it is very likely that we will no longer consider them as random. In science, therefore, randomness adopts the role of that which cannot be explained. An engineer named B. R. Gaines nicely summarised this view, writing: “Randomness shares Is this tile pattern random? The tile placement is in fact ordered but the large repeating pattern can make it appear random at first glance. Randomness can act in the same way. Only as we look for greater complexity will a pattern emerge. Image based on Bradley Hall, the former Maths Building at Dartmouth College.
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www.bluesci.org
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ALVY & MICROSIERVOS
with such basic phenomena as space and time the property that the more one knows about it the less one’s knowledge of it becomes.” The conceptual difficulties of randomness become even more obvious when researchers study how well we actually understand it. Experiments repeatedly show that people of all ages are not that good at explaining events using randomness. Many people, for example, when given a sequence of ten coin tosses that all resulted in heads, will predict that the eleventh toss will be tails, forgetting that the outcome of that toss is no less random than the previous ten tosses. Other examples show that people are generally not very good at determining whether an event is random. Most people would be fooled by the web-like image shown on the right, thinking that it depicts a pattern; it actually displays winning lottery numbers, a paradigm random event. In life, the conclusion that there are patterns underlying everyday randomness can lead to superstitions or conspiracy theories. Part of our confusion comes from what we might call practical confusion: it is difficult to know, practically speaking, if an event is random or not. As randomness is a negatively defined concept, it is easier to prove that something is not random than prove that it is. But we have a deeper conceptual confusion about randomness concerning the shift from considering the individual to considering a group. Let’s return to the coin example. Whether the coin lands on heads or tails is entirely random. But we do know that over many throws – a group of throws – roughly 50% will result in heads, 50% in tails. Even though each individual event is random, in the aggregate we get a predictable order. Statistics make good use of such longterm patterns, but they also conflict with our intuitions. When statistical use of such patterns was first developed in the 19th century, people were very uncomfortable, particularly with statistics that displayed predictable patterns underlying human behaviour. Describing a famous American court case in which Benjamin Peirce and his son Charles
The graph was made using Spanish lottery results with a different colour for each number. The lines lie further away from the centre the more times the number came up.
used such statistical reasoning to prove a signature a forgery, Louis Menand writes, “What scandalised people about the Peirces’ testimony in the Howland will case was their apparent reduction of a human activity – signing one’s name – to a set of numbers.” In the present day we’ve become more accustomed to statistics, but if we took a closer look
“Patterns underlying everyday randomness can lead to superstitions or conspiracy theories” we’d notice the discrepancy between random events becoming predictable over time and our association of randomness with chaos and disorder. So what are we to make of all this, in the end? The confusions embedded in randomness reveal our affinity for deterministic explanations. Einstein refused to believe the conclusion that
randomness may be fundamental, concluding: “God does not play dice.” But our conceptual bias may not align with the world; it could very well be that randomness plays a much greater role in nature than we have thought. Some scientists are attempting to explore this possibility: a field named stochastics studies nature’s randomness and some systems biologists are finding that certain cellular processes may actually make use of fundamentally non-deterministic molecular behaviour. The results of such research, which would force us to view randomness as an important, freestanding concept, may do more to alter our view of nature than anything since Galileo. For our part, I think the example of randomness illustrates the complexity that underlies our concepts and our interaction with the world. At the very least, the next time we encounter a poll, we might want to think about what it is actually measuring. Natalie Vokes is a Part II student in the Faculty of Philosophy 27
HISTORY
The Evolution of Natural Selection Katie Taylor investigates whether Darwin deserves his title as the sole originator of the theory of natural selection This year marks the 200th anniversary of Charles Darwin’s birth. Events across the globe will celebrate this iconic naturalist as the father of the theory of evolution by natural selection. However, the same theory was simultaneously developed by Alfred Russell Wallace, independently of Darwin. We have come to regard Darwin as the sole originator of the theory but without Wallace’s contribution, Darwin might never have published his theory.
“Modern debates about the Wallace-Darwin affair have been largely inconclusive” In 1831, Darwin was invited aboard HMS Beagle by Captain Robert FitzRoy for a voyage that spanned the first half of the decade. Darwin made extensive geological and natural historical observations on the voyage, writing many letters back to England in which he detailed his findings. In July of the following year, Darwin began the first of his notebooks on the transmutation of species. It was almost twenty years later that Darwin first heard from Alfred Russell Wallace, a naturalist who made a living selling specimens commercially. Wallace’s letter has never been found but Darwin’s response of May 1857 shows that he had read Wallace’s paper in the Annals and Magazine of Natural History. This paper, along with their correspondence, made it clear to Darwin that Wallace’s views closely resembled his own, a realisation which prompted Darwin to 28
write to Asa Gray, professor of natural history at Harvard, in September of that year summarising his ideas. By doing this, Darwin ensured that the leading American botanist of the time could testify to Darwin’s line of thinking. Darwin was not alone in recognising the similarity between Wallace’s ideas and his own. Charles Lyell, a prominent geologist and naturalist, had also noted the similarity between the two men’s ideas when he first recommended Wallace’s Annals paper to Darwin. On 18 June 1858, Darwin forwarded a manuscript paper to Lyell on behalf of Wallace, writing in an accompanying letter that “if Wallace had my [manuscript] sketch written out in 1842 he could not have made a better short abstract!” Darwin also asked Lyell to return the manuscript as soon as possible so that he might send it to journals for publication if Wallace could be made to agree. Just one week later, however, Darwin wrote another letter to Lyell asking his advice about whether to publish Wallace’s manuscript. Darwin pleaded that “[t]here is nothing in Wallace’s sketch which is not written out much fuller in my sketch copied in 1844, and read by Hooker some dozen years ago.” Recognising the urgency of the situation, Darwin told Lyell that he would be prepared to publish immediately “a sketch of my general views in about a dozen pages or so.” This would establish Darwin’s priority in the matter but he was also seeking Lyell’s advice as to whether such a move would be honourable. To 19th century natural historians, gentility was often just as important as scientific merit. Darwin wanted to
have his twenty years of hard work acknowledged, yet simultaneously felt the pressure for civility that the community of naturalists imposed. “I would far rather burn my whole book than that he [Wallace] or any man should think that I had behaved in a paltry spirit”, he wrote to Lyell. Darwin asked that Lyell forward his response, along with Darwin’s own letter expressing his moral quandary, to Hooker so that he might “have the opinion of my two best and kindest friends.” These two friends also happened to be firmly established among the gentleman naturalists of London. Lyell and Hooker quickly settled the matter on 30 June when they sent a collection of papers to the Linnaean Society of London.The pack comprised of a 1839 manuscript by Darwin, copied for Hooker to read in 1844, an abstract of the letter that Darwin had written to Asa Gray in October 1857, to show that Darwin’s views had not changed since 1839, and Wallace’s manuscript of February 1858.
“We should remember Wallace as a different variety of naturalist” Wallace’s manuscript was presented with an account of Darwin’s keen support of the paper as well as his desire to have it published. Darwin’s second letter to Lyell, in which he debated whether he himself could publish honourably, is not mentioned. Instead, Lyell and Hooker wrote that they agreed with Darwin that Wallace’s manuscript should be made public but only on the www.bluesci.org
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insights on the transmutation of species. Most naturalists ventured abroad only for a brief period to collect enough specimens for personal use. Through being semi-permanently stationed in exotic climates, collecting numerous specimens of each species to sell to a number of buyers, Wallace was inevitably exposed to a far wider variety of specimens than many contemporary naturalists. Indeed, Darwin himself requested specimens from Wallace over the course of their correspondence. In this way, Darwin benefited from Wallace’s work; if not from his ideas then
certainly from the specimens that the exotic collector supplied for the stay-athome naturalist. On the 200th anniversary of Darwin’s birth we should also remember Wallace, not as a direct competitor with Darwin, but rather as a different variety of naturalist vital to the development of the discipline of natural history. To find out more see the Darwin Correspondence Project: www.darwinproject.ac.uk Katie Taylor is a PhD student in the Department of History and Philosophy of Science SONIA AGUERA
condition that Darwin’s thoughts, now established for many years, were also disclosed. In presenting this collection of papers to the Linnaean Society Lyell and Hooker explained that they were “not solely considering the relative claims to priority of himself [Darwin] and his friend [Wallace], but the interests of science generally”. Lyell and Hooker cast the presentation as a temporary measure to make some important findings public “while the scientific world is waiting for the appearance of Mr. Darwin’s complete work”. In recognising the similarity of Wallace’s ideas to Darwin’s, Lyell and Hooker gave Darwin the right to produce an extended work on the theory of evolution by means of natural selection. This was the work that we now know as On the Origin of Species. Modern debates about priority in the Wallace-Darwin affair have been extensive, but largely inconclusive. This is partly because of the missing first letter that Wallace sent to Darwin, yet also because the priority question is the wrong one to ask. Lyell and Hooker wrote that Darwin and Wallace, working independently, “may both fairly claim the merit of being original thinkers in this important line of inquiry”. It is therefore more interesting to ask why Darwin is remembered as the sole discoverer of the mechanism of natural selection. One part of the answer is simply that Darwin was familiar with established members of the community of gentleman naturalists, whilst Wallace was not. Regular contact with Lyell and Hooker for many years meant that Darwin had made his views known to those people who had the power to publish them. Wallace, collecting in the far corners of the world and using specimens as a way to make money, as well as for scientific interest, was not a part of this community. He was geographically isolated from London and, perhaps more importantly, used his scientific work to make a living. Among the self-supporting gentlemen of the London scientific scene, this put a firm dent in his status as a researcher. It is little recognised, though, that Wallace’s work as a commercial collector might have been significant in his
Top left: Alfred Russel Wallace (1823-1913). Top right: Charles Robert Darwin (1809-1882)
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THE PAVILION
Today, more than ever, people are taking to Chesterfield
because Chesterfield concentrates on the important things in smoking. You smoke Chesterfields and find them cool and pleasant. You light one after another, and they really taste better. You buy pack after pack, and find them definitely milder.
For complete smoking satisfaction you can’t buy a better cigarette TEXT: 1940 Chesterfield cigarette advertisement
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ARTWORK: HEART STOPPING. No.3. 2008. Ink-jet print on paper. Digital mixed media montage. 840 mm x 1060 mm. PAULINE AITKEN
www.bluesci.org
INITIATIVES
From the Experts to Everyone Where would we be without science? The latest medical advances, the newest technology – we take it all for granted. But in 1830 there was real concern that science was in decline, prompting Charles Babbage, a professor at the University, to publish his book Reflections on the Decline of Science in England. This worry led to the birth of The British Association for the Advancement of Science, or the BA. The founding principles of the BA, proposed by William Vernon Harcourt, were “to give a stronger impulse and more systematic direction to scientific inquiry; to obtain a greater degree of national attention to the objects of science, and a removal of those disadvantages which impede its progress; to promote the intercourse of the cultivators of science with one another, and with foreign philosophers.” The first meeting was held in 1831 and the association has met annually since, interrupted only by the war years.
“The BA’s annual meetings have evolved into the Festival of Science” Originally, the meetings were used to announce major scientific advances and, in 1860, staged one of the most famous debates in history when T. H. Huxley and Samuel Wilberforce argued Darwin’s evolutionary theories published in On The Origin of Species the previous year. The BA was instrumental in the development of communication through scientific literature and produced its own reports on the state of science. The BA Lent 2009
BRITISH ASSOCIATION
Lindsey Nield explores the public understanding of science with the British Association
insists that science should not be just for an elite few. “The role of the BA is to break down those barriers and make science accessible and interesting for everyone”, says Joanna Rooke, Manager of Regional Programmes. The BA’s annual meetings continue, but have now evolved into the Festival of Science. This week-long event takes place at a different university each year, with hundreds of the best scientists and science communicators informing the public about the latest developments in research. In 2008, the festival was held in Liverpool and offered a host of hands-on activities such as setting off rockets and digging for fossils, as well as more serious talks aimed at families, the public and professionals. National Science and Engineering week is another of the BA’s annual events. Nationwide, a range of organisations and individuals, including schools, hospitals and museums, arrange events aimed at taking science to the public. Last year, an estimated 3500 events took place, with over 1.4 million participants. The BA currently has 34 regional branches that arrange activities for their local communities. Each branch has a committee working independently to arrange events that are of interest to themselves and the public. The traditional lecture is an old favourite, but some ideas are more innovative. In Bristol, the
university medical students share their experiences with the public at Meet-aMedic, and in Merseyside, science buskers take demonstrations out onto the streets. The map of branches in the UK currently has a gap in East Anglia, so the BA is extending their network to include Cambridge. A new branch will offer a wide range of roles for volunteers: events need to be organised and publicised, funds need to be raised. People join the branches for the opportunity to learn new skills, make new friends, or simply for the love of explaining science. Natalie Broadhurst, who will oversee the fledgling branch in Cambridge, says that the BA will encourage creativity. The branches are what volunteers make of them and original ideas are vital to get the public enthused about science. Science and its applications are essential in our modern world and public support is crucial. The BA is helping to keep public interest alive by providing more avenues for people from all backgrounds to get involved with science. The Cambridge branch is looking for volunteers. Email Natalie.Broadhurst@ the-ba.net or attend the first meeting on 21 January in the Council Room of the Old Schools, Trinity Lane at 6pm.
Lindsey Nield is a PhD student in the Department of Physics 31
LETTERS
Dr Hypothesis Dear Dr Hypothesis, I have trouble in the afternoons keeping alert and getting my work done. How can I best improve my performance during those long afternoons? Sleepy Sue
DR HYPOTHESIS SAYS: You’re not in any more imminent danger than you have been before! Even if terrorists have gathered enough uranium, the level of enrichment will still be very low. Uranium comes in two main isotopes, the low-abundance fissile U-235 and the abundant lowfissile U-238. For commercial reactors, Low Enriched Uranium (LEU) is used, which contains less than 20% of the unstable 235 isotope. This is relatively easy to make, whereas weapons-grade uranium requires at least 85% U-235 and is considerably more energy and time consuming. This said, so-called weapons-usable grade is anything above 20%, although this requires specialised knowledge in implosion techniques to make a workable bomb.
ADAM MOUGHTON
DR HYPOTHESIS SAYS: Dr Sara Mednick from the University of California certainly thinks she has the answer. In a recent study undertaken there, they pitted the performance of three groups against each other: one on a caffeine pill, one on a two-hour nap and one on a placebo. Those who took naps performed better than the caffeine group in all areas, with the placebo group outperforming the caffeine group in the motor tasks. Perhaps another thing to take away from this is that the nap takes two hours, the pill requires 20 seconds to take, and the placebo takes no time at all.You may underperform in the placebo or even in the caffeine case, but you have an extra two hours to do it in!
Dear Dr Hypothesis, I heard recently that terrorists have gathered enough uranium together to make a nuclear weapon. Is the world in imminent danger? Worried Wilma
Stay Alert
Dear Dr Hypothesis, I’m a film fan and the other day I was watching one of my favourites, Memento. The main character has a memory disorder where he cannot remember anything from more than five minutes ago. Do these conditions actually exist? Movie Mike DR HYPOTHESIS SAYS: The first similar case was of a patient known as ‘HM’. After a severe head injury resulted in a seizure disorder, aged 27 he underwent an operation to remove slivers of his brain. The seizures stopped, but during the operation an area near his hippocampus was damaged preventing him forming new memories. He retained his short-term memory – the events of the last 20 seconds – leaving him oblivious to his life post-operation. However, that said, learning tests showed that he was able to create new motor skills, whilst having no conscious recall of having done the task before - the first ever evidence of implicit versus explicit knowledge. HM, or Henry Molaison, lived a full life, enjoying crossword puzzles, bingo and watching TV but sadly died last month from natural causes at the ripe old age of 82.
Email Dr H with all your scientific conundrums drhypothesis@bluesci.org
Corrections and Clarifications In our article “Carved by the flow” (Issue 13, Michaelmas 2008) we wrongly stated that Julien Vermot was a member of the MRC Laboratory of Molecular Biology (LMB). He is actually based at the California Institute of Technology. The LMB is also
32
not part of the University of Cambridge although its graduate students are registered at the University. We also wrongly identified Ciara Metcalfe as a third year medical student. She is in fact a PhD student at the LMB, studying molecular and cell biology.
We are very sorry for the embarrassment and inconvenience caused. Finally, the cover image for Issue 12 went uncredited. We are very grateful to Marwah Hassan for the use of her sunflower picture entitled “The Heliotrope”.
www.bluesci.org
squash Interested in journalism? Come to the Varsity Squash and find out how to get involved with Cambridge’s oldest student newspaper. Meet the editors and their team for drinks and to find out the opportunities available.
See the newspaper for more information and venue location, or visit www.varsity.co.uk/ All years welcome. Volunteer ad:Layout 1
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Careful observation | Revolutionary thinking | Global influence
Call for Volunteers! The Darwin Festival Team is looking for enthusiastic, reliable and committed volunteers to assist during the Festival week (5-10 July 2009) and also in the weeks prior. Benefits include access to sessions, complementary tickets to evening events and opportunities to meet the worlds leading Darwin experts. Please register your interest at www.darwin2009.cam.ac.uk/
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