BlueSci Issue 17 - Lent 2010

The Cambridge University science magazine from

www.bluesci.co.uk

9 771748 692000

ISSN 1748-6920

17 >

Cambridge University science magazine

Lent 2010 Issue 17

FOCUS Can we prevent growing old and what would it mean if we could?

Science Meets Dance . Personal Pills Richard Feynman . Animal Research . Superconductivity

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Hangover Hell

The morning after the night before

Einstein

100 years of E=mc2

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Risk & Rationality

Looking Beyond

Astrobiology

When to trust your instincts

Crossing the great divide: the art of astronomy

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Issue 7 Michaelmas 2006

The Energy Crisis What are our options?

Mars or Glory A giant leap or a distant view?

New Parts For Old

The future of organ transplants

Our Origins

Stem Cells

What’s all the fuss about?

The genes that make us human

Face Recognition

Mind-reading computers and brain biology

Mobile Dangers

AIDS: 25 Years On The Sound of Science New perspectives on music

• The Science of Pain • World of the Nanoputians • • For He’s a Jolly Old (Cambridge) Fellow • Designer Babies •

• Robots: the Next Generation? • Mobile Medicine • • Climate Change • Forensic Science •

• Artificial Intelligence • Obesity • • Women In Science • Genetic Counselling •

• Hollywood • Science & Subtext • • Synaesthesia • Mobiles • Proteomics •

The Future of Science

Are phones really a healh risk?

Past, present and future

Opinion

Chocolate

Foreseeing breakthroughs in research

Views from Cambridge

Why do we love it?

• Drugs in the Sewage • Quantum Cryptography • • Time Truck • Gaia • Pharmacogenomics •

• Grapefruit • Dr Hypothesis • • Probiotics • Quantum Computers •

• String Theory • Schizophrenia • Antarctica • • Science and Film • Teleportation • Systems Biology •

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Deadline for next issue is 12th February 2010 Contact editor@bluesci.co.uk to get involved with editing, graphics or production cover_LN

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The Future of Neuropsychiatry Unraveling the biological basis of mental health

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The Large Hadron Collider

Biometrics Big Brother is fingerprinting you

Europe’s £5 billion experiment

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Synthetic Biology

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No Peppered Myth

An unexpected fuel source

Darwinian Evolution in Action

Brain Barometer

Darwinian Chemistry Biological Warfare

Does biodefence research make us safer?

A Natural Collector The story of a Victorian zoologist • Fair Trade with a Difference • Science and Comic Books • • Proteins that Kill • Human Evolution • Enterprise in Cambridge •

Sea Monsters In the wake of the giant squid

Ruby Hunting • Science Blogging • Extremes of Pain The Mullard Observatory • The Government’s Chief Scientific Advisor

First Predicted in 1895

Trickery

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Physics of Human Behaviour

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Saliva’s Secrets . Aubrey de Grey Appetite Control . Biofuels . Science and the Web

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Crowd Control African Rock Art . Intelligent Plants . Physics of Rainbows Sci-fi . Human Nutrition Research . Fish Ecology

Global Warming Mis red Action att it C rib ute ru d s nc cie h nti fic dis co ve G Influential Science Reporting rie Puls reen s

Saccades and Disease

Selection of the fittest molecules

• Poincaré Conjecture • Science Documentaries • Pharmaceuticals • • Human Uniqueness • The Whipple Museum • RNAi • • Stock Markets • Parliamentary Office of Science and Technology •

2009

Iridesc

The Future of Fuel

All For Shrimp

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Colour

Hydrogen Economy

Conservation of marine environments

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The Challenges of Engineering Life

Mining the Moon

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Contents

Features

Regulars

6

Getting the Girl

3 4 5

On The Cover News Pavilion

8

The Perfect Conductor

22

Behind the Science

24

Perspective

25

Away From the Bench

26

Arts and Reviews

28

History

30

Technology

31 32

Book Reviews Dr Derisive

10

Natalie Lawrence illustrates the bizarre mating habits of the animal kingdom Jack Gillett discusses the current uses and potential of superconductivity

Mind Over Matter

Amy Miller considers why science and maths can be so hard to learn Have We Got a Pill For You? Warren Hochfeld explores the inadequacies of prescription drugs

Anja Komatar examines the process of combining machine systems and human-like language

12 14

16

Teaching Computers to Speak

FOCUS

The End of Ageing?

BlueSci looks at the biology of ageing, how research is helping us to understand and overcome it and the impact on society if we could live longer

Jake Harris looks at the life of Richard Feynman behind the science Ian Fyfe gives his perspective on why rejecting religion is bad for science Kathelijne Koops roams the African rainforest to study chimpanzee culture Cat Davies talks to Nicola Clayton about her collaboration with the Rambert Dance Company Lindsey Nield traces the contributions and controversies in the history of animal research Fernando Ramos looks to the future of web technology

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Contents

1

Ian Fyfe

Issue 17: Lent 2010

Editor

Editor: Ian Fyfe Managing Editor: Cat Davies Business Manager: Michael Derringer

into the new millennium, it is becoming more important than ever for scientists to think about the context of their work within society. In this issue of BlueSci, FOCUS explores our knowledge of ageing and how we might use this to increase our life span. The science may be impressive, but what would the impact be on our society and our species?

You’ll also find two new regular in this issue. Perspective aims to present one view on a debatable topic and provoke your own thoughts – the rejection of religion by science is the topic for this issue. Behind The Science ten years

Sub-Editors: Shauna-Lee Chai, Wing Ying Chow, Alex Hyatt, Anja Komatar Second Editors: Chris Adriaanse, Antje Beyer, Harriet Dickinson, Jesse Dunietz, Bárbara Farreira, Jake Harris, Heather Hillenbrand, Anja Komatar, Natalie Lawrence, Jessica Robinson, Raliza Stoyanova, Gemma Thornton News Editors: Swetha Suresh, Katherine Thomas News Team: Taylor Burns, Wendy Mak, Laura Soul Book Reviews: Jessica Robinson, Swetha Suresh, Djuke Veldhuis Focus Editors: Taylor Burns, Chris Adriaanse Focus Team: Anders Aufderhorst, James Birrell, Alex Jenkin Dr Derisive: Mike Kenning Pictures Editor: Rosie Powell-Tuck Production Team: Chris Adriaanse, Shauna-Lee Chai, Alex Hyatt Cartoonist: Alex Hahn Cover Image: Rohan Pethiyagoda Jr Distribution Manager: Katherine Thomas Publicity: Matt Child

ISSN 1748-6920

Varsity Publications Ltd Old Examination Hall Free School Lane Cambridge, CB2 3RF Tel: 01223 337575 www.varsity.co.uk business@varsity.co.uk BlueSci is published by Varsity Publications Ltd and printed by The Burlington Press. All copyright is the exclusive property of Varsity Publications Ltd. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, without the prior permission of the publisher.

takes a new angle on the profiling of scientists and reveals the private lives that have been eclipsed by academic achievement; we start with Richard Feynman.

We also explore the interaction between science and dance, how and why animal research has changed, the implications of cloud computing and more.

You can also read about mating behaviour, superconduction, personalised medication and computer language, and if you have trouble understanding any of that, you can even find out why in Mind Over Matter.

There’s plenty to get you thinking, so take a few minutes to have a read. if

Cat Davies Managing Editor

recently remarked that what teachers call ‘copying’, she sees as ‘working in teams’. Smart lass. Future spindoctoring aside, her fondness for teamwork reminded me of the all-round brilliance of sharing skills and ideas. Here at BlueSci we’ve had a great start to the year with lots of new writers and editors on board, as well as new contributors in graphics and production.

The breadth of themes in this issue reflects the range of specialisms we have amongst BlueSci members. Over the last few weeks they have given me crash courses in pharmacogenetics, ethology and low-temperature physics, and have managed to

my teenage niece

get a cognitive scientist such as myself excited about these topics; a testimony to their skills of engagement, flair and patience. Our new feature on the private life of scientists has also got me thinking about how we spend our time away from the bench or the library. In these dark gloomy months when money and sunshine are tight, working on BlueSci restores my faith that people are willing to spend a bit of time and energy sharing their knowledge and enthusiasm for science communication. If you’d like to get involved, visit www.bluesci.co.uk or email me at managing-editor@ bluesci.co.uk. cd

About us: Established in 2004 to provide a forum for science communication, each term BlueSci publishes the best science writing from across the University. As Cambridge’s longest running science magazine we combine high quality writing with stunning images for a truly unique magazine.

Guaranteed to get you thinking.

President: Ian Fyfe Secretary: Alex Hyatt Treasurer: Jessica Robinson Publicity Officer: Shauna-Lee Chai

2 Editorial

Lent 2010

Habitat Hopping The Cambridge University science magazine from

Lent 2010 Issue 17

Cambridge University science magazine

9 771748 692000

FOCUS Can we prevent growing old and what would it mean if we could?

Science Meets Dance . Personal Pills Richard Feynman . Animal Research . Superconductivity

Endangered frogs in Sri Lankan forests have been able to settle in regenerated tea plantations

frog species known to inhabit the native forest nearby, thirteen of them (ten of which are endangered) have now settled in the site’s exotic vegetation.

Conservation of amphibians is important for the world’s ecosystems. They provide food for prey, such as birds and lizards, and are in turn predators of insects, including pest species. They serve as valuable ‘indicator species’ for environmental quality, and tadpoles control algae in streams and ponds. From a human perspective, the skin secretions of some amphibians have antimicrobial, antifungal and analgesic properties from which novel pharmaceuticals have been developed.

Rohan’s study suggests that some amphibians categorised as endangered may be tolerant of disturbed or altogether novel habitats. This substantially lowers their risk of extinction and allows conservation action to be focused on habitat-specialised species that may be more sensitive to environmental degradation and therefore need more urgent attention.

Katherine Thomas is a PhD student in the Department of Physics

ROHAN PETHIYAGODA JR

ISSN 1748-6920

17 >

www.bluesci.co.uk

this issue’s cover image shows the endangered saddled tree frog Polypedates eques, which lives in the cloud forests of Sri Lanka. It was photographed by Rohan Pethiyagoda Jr, a third-year natural sciences student, while on a recent field trip to conduct a frog census.

The world’s frogs are disappearing. According to the latest assessment by the International Union for Conservation of Nature, nearly one third of amphibian species world-wide are threatened with extinction and 35 species are now extinct. Of those species confirmed to be extinct, 21 were endemic to Sri Lanka.

Habitat degradation is thought to be the main driver for the demise of amphibians in Sri Lanka, where 51 species are threatened with extinction. Less than two per cent of the island’s original rainforests remain. During British colonial rule, large swathes of forest were cleared for rubber, coffee and tea plantations. This, along with subsequent demand for agricultural land by the island’s growing population, has put a huge strain on Sri Lanka’s biodiversity, in particular its unique amphibians.

Rohan worked on a 50 acre site that used to be a tea plantation. In 1999, as part of a restoration initiative, the tea was removed and the forest was allowed to regenerate. Now, less than a decade later, the site is covered with dense vegetation. However, rather than indigenous tropical forest plants, it is populated mainly by two foreign species; an Australian tree (Acacia) and a tropical American shrub (Austroeupatorium). These were introduced to the island in the 1900s as exotic garden plants. These two species now occupy more than 70 per cent of the study site. While this has important implications for restoring Sri Lanka’s mountainous rainforests, it is not only the plants that make this study site so special.

Ten endemic, endangered frogs have made the former tea plantation their home. Frogs are known to be very selective of habitat, and hardly any are found in the tea plantations surrounding the study site. Of the fifteen

ROHAN PETHIYAGODA JR

Katherine Thomas examines how frogs are responding to conservation efforts

Lent 2010

On The Cover 3

News

The latest Cambridge news and research.

Check out www. bluesci.co.uk for weekly science news updates during term

scientists and archaeologists have found that the ancient Nazca civilisation, who lived in the valleys of south Peru 1,500 years ago, caused their own downfall by tampering with the ecosystem that supported them.

The team, led by Dr David Beresford-Jones of the McDonald Institute for Archaeological Research at Cambridge, used plant remains and pollen samples to show that the Nazca gradually cleared away the nearby huarango forests to make way for their own crops.

The huarango tree was a vital part of the ecosystem, enhancing soil fertility, fixing nitrogen and helping to hold the Nazca’s irrigation channels in place. Together with providing fuel and shelter, this allowed settlers to survive in the otherwise harsh desert environment.

“In time, gradual woodland clearance crossed an ecological threshold,” explains Dr Beresford-Jones.

This left the landscape vulnerable to an unusually large El-Niño flood one year, which destroyed all the crops and irrigation channels. Further agriculture was almost impossible and future generations suffered.

Had the forest clearance not reached the critical point, the flood would have been far less devastating.

Even now people continue to illegally destroy huarango forests for charcoal. The story of the ancient settlers highlights the importance of ensuring that equally fragile ecosystems are protected. ls

Breakthrough in leukaemia research

iSTOCK

iSTOCK

The fall of the Nazcas

from the Wellcome Trust and Cancer Research UK Gurdon Institute have discovered that leukaemia has a previously unknown genetic switch. A gene called JAK2 has a nuclear function in the cell, and when it is faulty, as in most leukaemia cases, it can cause cancer.

Leukaemia is a cancer of the blood and bone marrow that occurs when blood cells, usually the immune system’s white blood cells, do not develop properly and divide uncontrollably. It is known to disrupt the body’s immune system, the central nervous system and the production of red blood cells.

Researchers at the Gurdon Institute discovered that faulty JAK2 alters the cell’s messaging system and creates new pathways through which leukaemia can develop. The enzyme encoded by the mutated gene affects histones (proteins that order and regulate DNA) in a way that inappropriately changes which genes are switched on and off.

This discovery is particularly timely since JAK2 inhibitors are currently in clinical trials for the treatment of myeloid leukaemias. As surgery is often not an option with leukaemia, any opportunities for developing intracellular treatments are immensely valuable, making the Cambridge researchers’ discovery highly significant. tb

researchers

Pesky pests no more!

MOHD IZAL ISMAIL

jan-henning dirks,

4 News

Christofer Clemente and Walter Federle from the Department of Zoology have found a new eco-friendly method of repelling insects using a surface coating made of polyimide resin that causes insects to ‘slip’.

Insects are normally able to walk across slippery surfaces with ease by secretion of a fluid (a mixture of oil and water) from tiny pads on their feet. This fluid acts as a ‘glue’ to hold them in place. The new repellent surface turns this secretion into a lubricant.

The coating absorbs water from the ‘glue’, leaving behind just the lubricating oily layer.

In lab tests, glass rods were coated with a variety of materials, including non-stick Teflon and the new

resin. As cockroaches climbed these rods, researchers measured the frictional force between the surface and the insects’ feet. The new material reduced the friction by about 60 per cent compared with Teflon, causing the cockroaches significant difficulty in climbing the rods.

The new coating could be used to control any insect that relies on the same mechanism for surface adhesion. As the material is both durable and non-toxic, it could have wide-ranging applications, including food containers, clothing and furniture. The next step is commercialisation to allow further development and marketing of this technology. wm Lent 2010

In chemistry, highly complex behaviour can follow from a number of simple rules.

Drawings can be made by looking at the ways of developing complex, and profound, patterns from simple structures and techniques.

Encoding, Decoding and Interpetation Ink on paper Rika Newcombe

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Getting the Girl

Natalie Lawrence illustrates the bizarre mating habits of the animal kingdom

VERONIKA KANTOROVITCH

Some male lions share females rather than fight to be head of the pride (right)

JOHANNA

when it comes to mating, following the crowd’s way of doing things just won’t pay off if you’re at the back of the queue. For this reason, male mating behaviour is the most ferocious example of evolutionary jostling. Rather than lose out by trying to compete in one specialised way, males have developed an array of strategies that sidestep the competition. As a result, otherwise less attractive males manage to do rather well for themselves.

Many male birds and mammals can sire offspring on the sly, even if they fail to court females, by engaging in cuckoldry. Dunnocks, or hedge sparrows, (Prunella modularis) are a well-studied example. If a male does not find a female to nest with, he may discreetly court an attached female when her mate is not looking. Females are willing to engage in such extra-marital relations because two males will contribute to parenting duties, both thinking that they have fathered the nestlings. However, the females’ official mates are not generally so sanguine about these unorthodox arrangements; the male guards the female closely and periodically pecks at her cloaca, the opening

6 Getting the Girl

of the reproductive tract, to make her eject other males’ sperm. That said, attached male dunnocks will also try to father a few extra-marital sprogs if at all possible.

Alternatively, males may be more open in their sharing of females. Rather than risk solitary battle to be the head of a pride, some male lions form small gangs, usually with relatives. This greatly increases their chance of taking over a pride and makes it much less likely that they will be ousted by incoming males. A single male’s tenure in a pride is often only about two years, but groups can remain in place for much longer. Length of tenure is important for reproductive success, since new males habitually kill the cubs already present in a pride so that females are quickly ready to mate again. Even if a male is not the group alpha, it may be well worth sharing the females if he stands a far better chance of getting to mate at all than he would alone.

Other males may not engage in run-of-the-mill courtship at all, but instead ride on the efforts of others. Male field crickets (Gryllus species) broadcast a mating call to attract nearby lady crickets. Unfortunately, this also causes nearby parasitoid wasps to make a beeline for the male in question, with dire consequences. About 14 per cent of cricket males do the sensible thing and keep quiet. However, to ensure that they do not lose out in the mating stakes, they situate themselves close to singing males, who are risking attack by the parasitoids. For the lurking males, this lowers the chance of being attacked, but means that they are on hand to entertain any females who like what they hear.

In carpenter frogs (Rana virgatipes), some males use this trick to appear more attractive. Males call to display their general machismo – the pitch Lent 2010

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and volume of their call reflects their size. Smaller males, rather than singing in vain amongst more well-endowed competitors, locate themselves close to large-sounding males, ready to pounce on any enticed females.

Environmental circumstances force some males to try an alternative tack. Male Orthophagous dung beetles usually have large horns with which they fight other males and diligently guard nest burrows while females see to domestic tasks like laying eggs. If, however, a male does not manage to attain sufficient body size during growth, due to environmental factors, these horns do not form.

He becomes a ‘sneaker male’, unable to fight other males but instead able to burrow behind guarding males and secretly mate with their females. Sneaker males also have bigger testes, so may be very fertile.

It seems that they are cutting their losses – there is little to gain from being a small-horned male, so they might as well direct their resources to more fruitful endeavours.

In other cases, a strategic re-think can be rather more drastic. Most species of coral-reef fish, such as spectacled parrotfish (Scaridae species), change sex through the course of their lives. This change in both behaviour and physiology can happen surprisingly rapidly over a matter of days. As a male becomes older and larger, the best way to maximise his reproductive success may be to become a female, since larger females are more fecund and produce more eggs. This could be especially effective if there is a high proportion of males around.

Often, several mating strategies may be equally successful. In many species, this results in the persistence of several genetically distinct types of male. Populations of male pygmy sword-tailed fish (Xipophorus species) contain several different versions of a particular gene that affects growth rates. Different males therefore have different growth patterns. Some mature early but have diminutive frames, others grow slowly but mature into the females’ idea of hot stuff. To make up for slight stature, the small males aggressively chase Lent 2010

females rather than courting them. Large males needn’t try too hard because they are inherently more attractive. However, larger males also have higher mortality, so have shorter breeding lives.

This means that both male types have similar reproductive success, so both sets of genes are maintained in the population.

In species with genetically distinct male morphs, the smaller morph often mimics a female. This is frequently found in species of fish in which males brood the eggs after fertilisation. In round gobies (Neogobius melanostrobius), normal males are up to ten inches long and attract females with steroid signals and visual displays. After a female has deposited her eggs in the male’s shallow nest, he fertilises and guards them until they hatch. Smallmorph males are the size and appearance of females and use their feminine charms to beguile larger males into allowing them around their nests when a female is laying. Once she is finished, the small male nips in, fertilises the brooding male’s hard-won eggs and scarpers.

The persistence of more than two male types can also occur through cycles in sexual selection. Sideblotched lizards (Uta stansburiana) have three male morphs. Amongst females, the flavour of the month is generally the least common male. One year, ‘ultra dominant’ orange males may be all the rage. The next year, when orange males are the most common as a result of the previous year’s breeding success, yellow-throated sneaker males manage to get the most matings. The sneakers are in turn defeated by blue-throated males who have modest mating ambitions and carefully guard a few females. However, blue males are inevitably superseded by aggressive orange males with large territories, and so the cycle continues.

This variety of mating strategies demonstrates that sexual selection is one of the most potent forces behind evolutionary change. Otherwise unsuccessful males must metaphorically think outside the box if they are to get a bigger slice of the reproductive pie. Evolution has produced strategies that allow the underdogs to avoid competing on the same terms as the alphas.

These range from alternative behaviours and developmental pathways to genetically distinct male morphs. Such variation in tactics gives each individual a chance to win the most desirable of all prizes – the chance to fertilise some eggs.

Side-blotched lizards have three male morphs (left) and genetically distinct pygmy sword-tailed fish have different growth patterns (below)

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Natalie Lawrence is a second year Natural Sciences Tripos student Getting the Girl 7

UCK ELL-T POW ROSI E

The Perfect Conductor

Jack Gillett discusses the current uses and potential of superconductivity

EQUINOX GRAPHICS

JOHANNA

In superconduction, electrons form pairs that do not scatter and no energy is wasted (below)

in 1911 the leading lights of theoretical physics clashed over their predictions of how conductive materials would behave at very low temperatures.

Some believed that electrons would stand still in sufficiently cold conductors. Others thought they would move faster. The battle ended when Heike Kamerlingh Onnes, at the University of Leiden in Holland, discovered superconductivity.

Usually, passing electricity through a conductor produces heat. Electrons collide with ions in the conducting material and with other electrons, and are scattered. The energy from these collisions is converted into heat and wasted. The higher the electrical resistance of the material, the more heat is produced.

In a superconductor, vibrations in the material cause the electrons to form pairs that are able to flow through the material without scattering. Below the critical temperature of a superconductor, which varies between materials, thermal motion cannot break up these pairs; the conductivity is perfect and no energy is wasted.

The critical temperatures of superconductors are close to ‘absolute zero’, the lowest possible temperature equivalent to -273 degrees centigrade. For example, niobium has the highest critical temperature of the elemental superconductors and still requires the temperature to be below -263.8 degrees centigrade.

8 The Perfect Conductor

Superconductivity remained something of a curiosity for most of the 20th century due to the low temperatures required. It was not until 1957 that a Nobel prize-winning theory of superconductivity was proposed that suitably explained all of the effects observed at the time. This theory predicted a maximum critical temperature of -243 degrees centigrade. Such temperatures are incredibly low compared with those encountered in everyday life – the coldest place on earth is only -80 degrees centigrade. Nevertheless, the properties of superconductors are so unique that they are used despite the low temperatures required.

Superconductors are used to create large magnetic fields. According to Ampere’s law, when a current flows it generates a magnetic field. With the ability to carry a high current density, superconducting materials therefore produce a very large magnetic field. The most notable use of this is in MRI scanners, in which a strong magnetic field is used to map the locations of water molecules in the brain and provide an accurate three-dimensional brain scan.

Without superconductors, the space required to attain the necessary magnetic field would be prohibitive.

Superconducting magnets are also used in the Large Hadron Collider, the particle accelerator used to study the smallest particles in the universe.

Alongside perfect conductivity, superconductors have another remarkable property. When placed in a magnetic field, they become magnetised themselves so as to exactly cancel the external field. The superconductor attains a north pole aligned with the north pole of the applied field, so they repel one another like two bar magnets aligned the wrong way.

A superconductor placed above a large magnet will therefore levitate.

In Japan, lovers can be married on a floating magnetic plate, but the most commercial application of the levitation effect is the magnetic Lent 2010

Lent 2010

Iron arsenide based superconductor that superconducts at -235 degrees centigrade when some of the barium is replaced with potassium (left).

MAGLEV trains use superconductors to levitate above the track (below)

Jack Gillett is a PhD student in the Department of Physics

KRZYSZTOF ZIEBINSKI

CHRIS ADRIAANSE

levitation (MAGLEV) train. These trains float above the track, and this greatly reduces the drag force. A MAGLEV connects Shanghai airport to the city and reaches four hundred kilometres per hour during the eight minute journey.

Although superconductors have already found applications, the hope of zero-resistance electrical cables at room temperature is the motivation behind much research into superconductivity. Currently, ten per cent of all electricity is wasted in transmission.

This particularly affects renewable energy sources, because windy or sunny areas tend to be far from large populations. Superconducting cables would reduce this wastage.

Superconductors at room temperature could also create more efficient batteries. Since there is no resistance, a current flowing around a loop of superconductors will continue almost indefinitely (over 100,000 years according to calculations). Currently, we have to keep enough power plants running to maintain the peak load at all times, regardless of demand. Effective storage in batteries could allow significant reductions in the amount of power generated and would also help to balance generation from intermittent sources, such as solar power.

Although such room temperature superconductors are not yet available, a revolutionary series of new compounds were discovered in the late 1980s that display much higher critical temperatures. These materials, called cuprates, are based on a series of ceramic chemical compounds made up of copper oxide layers. Some of these materials superconduct at above -196 degrees centigrade, which is the boiling point of liquid nitrogen.

This discovery opened up new avenues for applications of superconductors, since nitrogen is much cheaper than lower temperature coolants like helium.

In addition, the high critical temperature shows that the cause of superconductivity must be radically different to that proposed in the 1957 theory. High-temperature superconductivity is still not fully understood, but if the maximum critical temperature turns out to be much higher than previously thought, superconductors may be easier and cheaper to use in future.

Despite the promise of the cuprate ‘hightemperature’ superconductors, development has been slow. Among other problems, there are serious

challenges in turning ceramic compounds into wires for transmission lines – imagine trying to make a tea cup into a cable. Consequently, the scientific community is constantly looking for new materials that display superconductivity.

Among other systems, carbon-60 Buckminster fullerene and graphite can be turned into carbonbased superconductors with the right addition of certain metals. Magnesium bromide was found to be a good superconductor only in 1999, despite having been well-known for over 100 years. A family of materials including certain uranium and plutonium compounds, called the ‘heavy-fermion’ superconductors, display a raft of interesting phenomena in which the electrons inside them appear to acquire an incredibly large mass when moving through the material.

Research at the Cavendish Laboratory in Cambridge involves another family of superconductors, the iron arsenides. Discovered to be superconducting in early 2008, these materials have the second highest critical temperatures to the cuprates, promising new clues about the nature of superconductivity at high temperatures. Just like the cuprates, these materials are made into superconductors by ‘doping’ – the intentional introduction of impurities into a compound to change its structure and electrical properties. An alternative method, discovered at the Cavendish Laboratory, involves applying very large pressures, which makes these new materials superconduct at quite high temperatures. Ongoing research involves trying to prise apart the effect of pressure and doping on the electrical and structural properties in these materials in order to inform further theoretical discussion.

Superconductivity is perhaps the most spectacular scientific discovery yet to find a significant foothold in the real economy. But the increasing use of superconductivity in niche areas together with an active research community and a growing superconductor industry may provide a warmer future for this revolutionary phenomenon.

The Perfect Conductor 9

ROSIE POWELL-TUCK

Mind Over Matter Amy Miller considers why science and maths can be so hard to learn within sixty seconds of meeting someone, we process a host of social cues that are amalgamated to form an overall impression of them. To do this, the brain must be capable of processing complex data with extremely high speed and accuracy. But compare this ‘social cognition’ with the common difficulties of ‘thinking scientifically’. Why can’t we exploit all this processing power and make maths, physics and chemistry as simple as sizing up a stranger? Are the difficulties we have in learning science down to a lack of brain power or due to science being intrinsically ‘hard’ to learn?

One of the challenges of science is that it requires our brains to work beyond their evolved capacity.

For example, to appreciate the large numbers that we encounter in the modern world, we often need to break them down into concrete ratios or multiples, like ‘lengths of a football field’ or ‘number of doubledecker buses’. It is impossible for us to appreciate large quantities or long spans of time because our brains evolved in an environment where they only needed to deal with about 200 people in a social group or 100 years of time. In evolutionary terms, we have never needed to count higher than this or to reason about abstract concepts. As a consequence

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The human brain is wired to evaluate situations and people, not to handle abstract concepts (right)

10 Mind Over Matter

our brains developed as ‘cognitive misers’, disinclined to waste valuable power on these tasks when what we need for survival is to be able to quickly and accurately evaluate situations and people.

Furthermore, ‘scientific thinking’ is not just a question of cognitive capacity, it also requires a certain set of cognitive skills. It involves the development of a hypothesis or question, accurate data collection and analysis as well as refinement of the hypothesis in light of the results. This requires abstract reasoning and logical thinking. Before sophisticated systems like the human body or complex theories like quantum mechanics can be understood, these cognitive skills must be developed.

The time this takes may account for more of the difficulty we have in learning science, even once we are capable of scientific thinking.

In the first half of the 20th century, the learning theorist Jean Piaget noticed that young children find it hard to think in the logical way required by the sciences. He suggested that, as children progress through several developmental stages, they slowly develop the necessary cognitive skills. More recent experimental work has found that the ability to handle abstract concepts, a key skill for science and maths, increases with the accumulation of knowledge and experience.

However, before these cognitive skills develop, we are already learning about the world. From an early age, babies and children are what psychologists call ‘naïve scientists’ – they develop and test theories about the movement and behaviour of objects and people. For instance, young babies show surprise if an object starts to move without another moving object touching it. As we grow up, our knowledge of the world is based on all the information we have collected and the theories that we have built up through experience.

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Science is partly hard to learn, therefore, because it involves ‘un-learning’ these theories that we’ve built up from observation over time. Through science, our knowledge of the physical world moves far beyond what we can perceive with our senses, and often turns out to be incompatible with experience. When a bus stops suddenly, we continue to move forward rapidly, according to Newton’s First Law, but what we experience is the sudden application of a sharp force from behind.

Similarly, it is difficult for both children and adults to believe that motion continues perpetually in the absence of an opposing force because our experience has invariably been that an object will stop moving unless it is continuously propelled. Such experience is so ingrained that it is hard to reverse.

As science and technology become more complex, ‘science literacy’ in society is becoming increasingly important. The public and our MPs need the skills and understanding to evaluate new medical and technological advances and make decisions about them. The 2003 ‘Frankenfood’ controversy over genetically modified crops is one of the most

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high-profile examples of how a lack of scientific understanding can have a real effect on the future of society. Education must produce a future generation of more scientifically literate adults, yet according to the Relevance of Science Education project, coordinated by the University of Oslo, a majority of 15-year-olds report being ‘turned off’ by science. This is reflected by the reduced numbers choosing sciences and mathematics at GCSE and A-Level. For example, the number taking physics at A-Level has halved in the last ten years. It is further demonstrated by the closures of 80 university science departments between 2001 and 2007. New ways to teach science could be the answer, and knowledge of why we find it so difficult to learn may help.

So if we accept that thinking and learning about science is never going to be naturally ‘easy’, what do we do about it? In the last 20 years, the issue has been considered critical for the future of society and gained a huge amount of attention. Research into how children develop cognitive skills has helped to identify the steps involved in acquiring the sophisticated thinking required for science. It also seems likely that we must play to our brains’ strengths as well as fighting our weaknesses. Research shows that if we’re motivated to achieve a task, we’re much more able to overcome our ‘cognitive miser’ tendencies and make more reasoned and accurate judgements. Science education needs to tap into children’s motivation and help them to break down challenging, abstract concepts and knowledge into the concrete and relevant. It may seem like ‘dumbing down’, but it could be exactly what’s needed to help us smarten up.

Young children are unable to think scientifically, but learn about the world through experience(left)

Amy Miller is an MPhil student in the Faculty of Education

Mind Over Matter 11

ROSIE POWELL-TUCK

Have We Got a Pill For You?

Warren Hochfeld explores the inadequacies of prescription drugs

The ‘one size fits all’ approach is often no better for drugs than for clothes (right)

It was Allen Roses, vice-president of genetics at the pharmaceutical giant GlaxoSmithKline, who admitted in 2003 the “open secret within the drugs industry”. Fewer than half of patients derive any benefit from some of the most expensive drugs.

To combat this, doctors and drug developers have recently been working together towards genetically tailored prescriptions that could revolutionise the pharmaceutical industry.

The aim of drug therapy is to administer the appropriate drug in the correct dose to produce the desired effect with minimum toxicity. The administration of a drug at an ordinary dose is usually followed by a gradual rise in drug concentration in the blood to a peak or steady state. If the concentration is within the therapeutic range, the characteristic response is expected.

However, an effective medicine for one patient may not work for another, even if they suffer from the same condition. This is because drugs are developed and approved on the basis of their general performance in large clinical trials.

Although the trials are essential to demonstrate the general efficacy of new drugs, they rarely, if ever, tell us which treatments are best for which patients.

Some drugs that are approved show an efficacy of less than 30 per cent in clinical trials. Together with the fact that about 90 per cent of today’s drugs work for only 30-50 per cent of patients, this makes prescribing them tricky. In fact, there remain few situations in which an individual’s response to drug therapy is reliably predictable.

It is therefore not surprising that the United States lists adverse drug reactions as the fourth leading cause of death behind heart disease, cancer and stroke. The annual toll is 108,000 deaths, more than 2 million hospitalisations and a $136 billion bill for illness induced by prescribed, FDA-approved medicine.

The burgeoning field of pharmacogenetics may be about to change this. Its ultimate goal is to provide

12 Have We Got a Pill For You?

a stronger scientific basis for selecting the optimal drug therapy for individual patients and to take the guesswork out of prescriptions. We all know someone who slurs after a small glass of champagne and someone else who can discuss celestial mechanics with intellectual clarity after several pints. This is happy-hour pharmacogenetics in action – genetic differences contributing to different tolerance of alcohol. Clinical pharmacogenetics works on the same principle.

Genetic differences often underlie differences in drug responses. Genetic information is encoded by the order of building blocks (nucleotides) along a strand of DNA. The sequence of nucleotides determines the genes that encode for hundreds of thousands of proteins, which are responsible for cellular function. As drugs travel through the body, they interact with many of these proteins. Even though 99.9 per cent of genes are shared by all humans, there are still millions of variations between people. These differences in genes can produce proteins that work differently; differences in proteins

HEATHER HILLENBRAND

“our drugs do not work on most patients.”

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Differences in DNA sequence can cause different responses to drugs (left)

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can result in different interactions with drugs and therefore different responses.

The prospect of examining a person’s entire genome, or at least a large portion of it, in order to make individual risk predictions and treatment decisions is within reach. The Human Genome Project has provided a wealth of genetic information to fuel the understanding of our genetic differences and their functional consequences. Dozens of companies have recently sprung up, quantifying and cataloguing human genetic variation and using algorithms to tease out correlations between genes and drug responses.

Outstanding in this technical revolution are DNA microarrays. These are glass microscope slides supporting thousands of microscopic spots arranged in a grid. Each spot consists of a DNA-based probe designed to detect the activity of a different gene.

Each spot has a known unique DNA sequence and will bind only to its complementary DNA strand. In this way, each spot acts as a probe to determine the expression levels of a specific gene in a collection of cells. In pharmocogenetic research, this can be used to quickly examine gene expression in a subject and compare it to drug response. In a handful of examples to date, doctors have used this information, in conjunction with a full and accurate description of clinical symptoms, to prescribe the

right drug for the right person at the right dose at the right time.

Although a straightforward glide into perfect, personalised medicine is unrealistic, pharmacogenetics in its infancy represents a structural model for efficient healthcare that is preventative, coordinated and evidence-based.

For more than 20 years, the industry has been dominated by ‘one size fits all’ blockbuster drugs, so pharmaceutical companies may remain sceptical.

The stakes are high and the future uncertain, but the real winners of genetically tailored drug therapy will be the patients.

Warren Hochfeld is a PhD Student in the Department of Medical Genetics

Poster and Image Competition Communicating your research to the public

How do Insec ts Both Attac h to Detach from Smooth Surfa and ces?

James Bullock and Walter Federle

The green dock beetle Gastrophysa viridula

Tarsus showing

Department of Zoology University of Cambridge

adhesive pads

The adhesive

hairs

Hairy

The Graduate School of Life Sciences challenges you to design a poster or image that explains your research to a non-specialist audience: • • •

Prizes up to £250 Categories for different research disciplines and stages Deadline for entries: Sunday 28 February

Recorded values

Progression

for friction force,

showing the

actual contact

contact area

and shear stress

of hair tips of

the dock beetle

produced by

a beetle’s foot

during a push

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pulls and pushes

The fine, fluid covered hairs of the foot pads close surface contact - meaning allow smooth substrate that even on a of over 100 times a single foot can generate forces the beetle’s body mass.

When pushing the foot, hairs peel individually the surface, reducing from attachment 5 fold. of the foot Pulling

distal

Attaching - Using

Pushing

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Push

specialised ‘hairy ’ and ‘smooth’ Detaching - Using adhesive pads the direction-de pendence of The Indian stick insect Carausius morosus the pads Tarsus showing adhesive pads The Peeling hairs during due to the angled a push - contact area and force hair design and flexible spatula decrease like tips

smooth arolium

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The soft fluid filled arolium again allows surface contact, intimate friction forces. generating strong adhesion As with the hairy and mediated by system these capillary bridges are secreted fluid. formed from

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The leg buckles when pus hed away from the body, detaching the pad - which is also able to rapidly peel from the surface.

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Pulling and pushing

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the leg of a stick

for friction force,

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contact area

attachment of

and shear stress

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the pad (pull),

produced by

and buckling

a stick insect’s

of the leg (push)

foot pads during

pulls and pushes

Part of the Cambridge Science Festival (8-21 March 2010) For details visit: tinyurl.com/gslsposterandimage2010 Participants must be MPhil, PhD or postdoc in the Graduate School of Life Sciences.

The winning image will be featured in the next issue of BlueSci magazine.

Sponsored by the Graduate School of Life Sciences, Qiagen and GE

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Have We Got a Pill For You? 13

SIE RO

Teaching Computers to Speak

CK -TU

LL WE PO

Anja Komatar examines the process of combining machine systems and human-like language

SONIA AGUERA

Programming a computer to use a vocabulary and grammar is not enough for it to produce meaningful language (below)

making computers that can understand and use human-like language is one of the most difficult problems to solve in computer science.

Uniting biologists, mathematicians, psychologists, anthropologists and computer scientists, the goal of teaching computers to speak is arguably part of the central problem in creating artificial intelligence.

Solving it could lead to a new generation of computers that are as intelligent as people.

For computers to be able to produce human language, they first need a vocabulary, for example; Peter, young, saw, a, an, apple, rhino, ate, big, see, the, giraffes, sees, notorious. But this is not enough. With a vocabulary alone, a computer cannot distinguish between meaningful sentences, such as “Peter saw an apple”, and strings of words like “Big saw the a ate rhino”; it has no means of combining the words into sentences that are meaningful to humans.

To construct meaningful sentences from a vocabulary, a computer, like humans, needs grammar – a set of rules for combining the words. The brute force approach would be to simply list all the possible grammatically correct combinations. This might work on small vocabularies, but with the hundreds of thousands of words in any human language, that would be far too time-consuming.

As a shortcut, words can be categorised into subsets based on their grammatical function. To capture this mathematically, we can introduce an equivalence

14 Teaching Computers to Speak

relation. If words can be used in the same place in a sentence, they are categorically equivalent to one another and therefore belong to the same subset.

So the vocabulary above would be split into nouns (Peter, apple, rhino, giraffes), verbs (saw, ate, sees, see), articles (a, an, the) and adjectives (young, big, notorious). This allows grammatically correct structures to be defined by combinations of the subsets. For example, defining adjective-nounverb-article-noun as a sentence gives us a variety of options, from “Young Peter sees an apple” to “Notorious apple ate a rhino”. However, this method still allows grammatically incorrect sentences such as “Apple see an big giraffes.”

The problem is that words from distinct subsets are not independent. For example, the correct verb form (see, sees, saw) depends on the subject and tense. To solve this, more restrictions are needed. Perhaps a set of verb stems (play, help etc.) could be combined with a set of suffixes (–ed, –ing etc.), and complemented with a set of auxiliary verbs that denote the tense (will, had, was etc.). Rules would be needed to define the correct combinations, and irregular verbs would have to be considered separately.

It soon becomes clear that even an apparently simple approach to teaching a computer to produce a simple sentence quickly becomes difficult. More complex sentences would require many more rules and restrictions. Even a complete vocabulary and a set of grammatical rules will still not allow a computer to actually understand humans and respond to them appropriately.

A different approach is to limit the topics of conversation we expect a computer to engage in. One example of this is ELIZA the computer psychiatrist, a program written in 1965 by Joseph Weizenbaum. ELIZA mimics a stereotypical psychotherapist. It focuses attention on the patient Lent 2010

JAMIE MARLAND

ROSIE POWELL-TUCK

and hence avoids answering questions. By using simple pattern matching techniques, ELIZA can determine a grammatically correct response to the patient and, in combination with a few standard phrases, this can seem convincing.

But ELIZA depends on the phrase structure of the input sentences and borrows most of the vocabulary from the patient. If “Peter saw an apple” is a grammatically correct sentence, then ELIZA works out that so are “Did Peter see an apple?” and “He saw it”. Fixed phrases, such as “Do you believe it is normal to...” can also be combined with input language. For example, ELIZA could use the structure of the sentence “Peter saw an apple” to convert it to a question and ask “Do you believe it is normal to see an apple?” So ELIZA merely rearranges patients’ words and encourages them to continue the conversation, it does not truly interact with them.

In contrast, SHRDLU was a system developed by Terry Winograd from 1968-1970 that could interact with an English speaker. Like ELIZA, its ability to converse was limited; it was confined to a tiny room containing geometric objects and could only talk about these objects. But it was an improvement in that there was a direct interaction with humans. It responded to commands such as “Move the blue box” and could also answer questions such as “Is there a bigger box than the one you are holding right now?” or “Where is the red sphere?” in a grammatically correct way. The key to the success of SHRDLU was that anything in its world could be described using only about 50 words, so the number of possible combinations was small enough to allow computation. But while its interaction with humans was direct and meaningful, it was still limited to just one subject that had little productive use.

However successful they may be in their own universes, ELIZA and SHRDLU are mostly useless in more complex situations. The simple rules of combining and transforming phrases sooner or later combine to form more complex rules and eventually generate grammatically incorrect sentences. They are

unable to capture the properties of human language in a way that makes them useful.

Nowadays, unimaginable amounts of data are stored on the internet, so statistical analysis of natural language is possible. Google Translate uses huge numbers of documents that are written in pairs of languages to develop and maintain a usable statistical automatic translation system. It simply counts how many times certain words occur close to each other and determines the most likely translation.

Google Translate is therefore capable of producing translations without having been programmed to recognise all possible combinations of words. It does not always produce grammatically correct sentences, but it usually captures the general meaning of the text. Despite this, it is still far from being able to replace human translators. This is especially true for less common languages, in which there are few texts with translations available.

Furthermore, this system is unable to produce language or interact directly with humans.

Teaching computers to use human language would transform their application. At the moment, non-specialists rely on computer scientists to write programs that enable them to use computers. Once computers learn to ‘speak’ and ‘understand’, every person could use their natural language to program them. Computers could also act as direct translators and allow easy communication between people who do not speak the same language.

The limited success of natural language processing systems demonstrates the difficulties involved.

However, the perseverance and large amounts of funding in this field show the importance of overcoming them. The potential benefits mean that scientists around the world, from many disciplines, continue to strive for a mathematical model of language that would enable conversation between people and computers.

ELIZA uses input and set phrases to produce language (above)

Anja Komatar is a first year Mathematics Tripos student Lent 2010

Teaching Computers to Speak 15

The End of Age

BlueSci looks at the biology of ageing, how resea and overcome it and the impact o 22 Katpitza

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TOM POWELL-TUCK

geing?

w research is helping us to understand pact on society if we could live longer Lent 2010

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the quest to prevent ageing is beginning to move slowly from science fiction to science fact.

Perhaps the most profound consequence of this revolution in longevity is the notion, now widely agreed upon within the biological gerontology community, that ageing is unnatural, unnecessary and certainly not inevitable.

In this regard, Tom Kirkwood, Cambridge alumnus and the director of the Newcastle Institute for Ageing and Health, can be considered a pioneer. Kirkwood has been at the forefront of educating the public about our current understanding of ageing, promoting his ideas during his 2001 Reith Lectures and in the House of Lords Science and Technology Select Committee report on scientific aspects of ageing. Kirkwood is trying to counter the view that most people hold of ageing, that it is an inevitable process and it is somehow programmed into our genes.

“We’re used to thinking in terms of a program of development for everything,” says Kirkwood.

“Naturally we accept a program of ageing. Rather, the body is programmed for survival and the reason we age is that, due to the intense biological competition for resources, there was never a need to invest in good cellular programs to ensure longevity. At the end of the day, how ageing actually plays out tends to be governed, to a very large extent, by chance.”

Kirkwood sees two principal lines of evidence against ageing being programmed – the first, evolutionary: “It’s almost impossible to find a plausible way for a program for ageing to evolve,” says Kirkwood. “The idea that there is a program in hypothetically old creatures just does not make sense.” We can find no biological evidence

Focus 17

If the mechanisms of the biological clock are elucidated, we may be able to slow or stop ageing

for it either. “You would expect there to be an organisational self-destruct program. What we in fact see is that in the last moments of someone’s life their vital organs are doing their utmost to keep them alive.”

This radical change in how we perceive ageing has been made clear by the recent recipients of the Nobel Prize for medicine and their research into the role of telomeres in ageing, as well as the burgeoning development of age-research institutes in the last decade, such as the Cambridge Interdisciplinary Research Centre on Ageing, the Oxford Institute of Ageing, and the Newcastle Institute for Ageing and Health. All investigate fundamental questions on how ageing can be defined scientifically and how it can be prevented. In addition, fringe groups like Aubrey de Grey’s Methuselah foundation have predicted that the first person to live to 1,000 may already be in our midst.

“In theory,” says Kirkwood, “it is possible to imagine that we can enhance the functioning of maintenance and repair processes [to prevent ageing]. Where I would part company with someone like Aubrey de Grey is the ease with which we can modify that to extend human life capacity. What we are seeing in our own research is exciting data to show how complex these mechanisms actually are. The idea that we can modulate these complex mechanisms is running way beyond current science capabilities – it is moving from science to almost a fantasy.” if ageing is not genetically determined,

then why do we age? Correlations between body mass, metabolic rate and life span observed in the early 20th century led to the ‘rate of living’ theory of ageing, which proposes that a faster metabolism

18 Focus

speeds up ageing. The mechanism behind this is suggested to be the cellular damage caused by free radicals, a by-product of metabolism.

Free radicals are molecules that contain unpaired electrons. Many are highly unstable and can easily rip electrons from other molecules. Free radicals produced in a cell will bump into biologically important molecules like DNA, proteins and lipids, modify their structures and alter their properties.

This damage can be repaired, but if there is more damage than the repair pathways can cope with, it accumulates over time. Such accumulation corresponds to what is seen in ageing; little change for most of an organism’s life, but fairly rapid decline towards the end.

In our bodies, free radicals are primarily formed as a by-product of respiration. Unwanted transfer of electrons to oxygen forms members of the reactive oxygen species (superoxide, hydroxyl and peroxide), some of the most aggressive reactive species that can form. All these species can cause significant damage in the mitochondria where they are produced but only hydrogen peroxide can cross the mitochondrial inner membrane and cause damage throughout the cell.

Antioxidants have been championed as miracle cures for ageing. They are the first line of defence against these reactive oxygen species and act by neutralising the free radicals to prevent damage.

Whilst their benefits may be exaggerated in adverts for anti-ageing cosmetics, there is some evidence that a diet containing more antioxidants can increase life expectancy. Consumption of foods that are high in antioxidants has so far produced mixed results in increasing longevity.

Another way to increase life expectancy is by restricting calorie intake. Studies in nematode worms, mice, fruit flies and primates have shown Lent 2010

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that caloric restriction reduces the likelihood of diabetes, cancer and cardiovascular disease and extends life. To date, this is the only lifestyle regimen that has been shown to delay the symptoms of ageing in a wide range of species.

Early studies suggest that similar benefits may be seen in humans. The ongoing CALERIE (Comprehensive Assessment of Long-term Effects of Reduced Intake of Energy) study in America has been running since 2007 and is constantly recruiting patients to participate in a long-term diet restriction experiment. A six month preliminary study indicated that a 25 per cent reduction in calorie intake has similar benefits to those seen in other animals.

The obvious way that caloric restriction may help is by altering rates of metabolism and free radical production. However, it appears that the mechanism may not be so passive. Caloric restriction causes huge changes in gene expression, increased levels of several proteins – including antioxidant enzymes and proteins involved in metabolism – and increased mitochondrial biogenesis. The net result is a reduction in free radical cellular damage.

By its very nature, free radical damage is random.

But as our understanding of specific ageing mechanisms increases, we will be able to exhibit some control. One of the most exciting mechanisms to have recently emerged is the role of telomeres. the nobel prize in physiology or medicine was shared last year between Elizabeth Blackburn, Carol Greider and Jack Szotak, the founders of telomere research. Telomeres are long repeated sequences of noncoding DNA at the ends of linear chromosomes that prevent loss of the coding DNA during replication.

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During DNA replication the telomeres are shortened. Telomere lengths are reduced with each cell division, leading to the eventual loss of genetic information that causes cell dysfunction and death.

If we can enhance the protective power of telomeres we may be able to extend lifespan.

The body already has an enzyme that does just that. Telomerase rebuilds telomeres to prevent the cell from dying and make them ‘immortal’.

However, it is only expressed highly in stem cells and cells that divide frequently, such as in the immune system; expression in most somatic cells is low. It is also expressed highly in cancer cells. This suggests that telomere shortening is a protective mechanism against cancer, stopping damaged DNA from replicating, but the side effect is that cells die and we age.

Telomeres are prone to damage from free radicals, resulting in double strand breaks or simply removal of large sections. The reactive oxygen species cause rapid telomere shortening and therefore premature ageing. Repairing telomeres and preventing free radical damage could allow cells to divide indefinitely, ultimately increasing our longevity.

Increasing telomerase activity has indeed been achieved at the cellular level. This has been shown to induce a 50 per cent increase in the lifespan of cancer-resistant mice. This not only provides hope for anti-ageing therapy, but could be important in new treatments for cancer. High levels of telomerase in tumour cells allow them to divide indefinitely.

If telomerase activity could be reduced in these cells specifically, tumour growth could be slowed or stopped altogether.

Telomere length is just one of the many contributing factors to ageing. Damage to mitochondrial DNA has also been implicated.

Mitochondria are the main sites of free radical production and damage to mitochondrial DNA may be important in ageing

Focus 19

How would our attitudes towards death change if it became even less common?

Mitochondria contain their own DNA, which codes for several of the core respiratory chain enzyme subunits. Since mitochondrial DNA is in close proximity to the major sites of free radical production, it mutates up to ten times faster than nuclear DNA. The mitochondrial mutator mouse is unable to replicate mitochondrial DNA correctly and mutations accumulate with each replication.

These mice show the signs of premature ageing.

There are still many unknowns, but what is clear is that the ageing process is a highly complex interconnected network of mechanisms that probably all contribute to cell death and the functional decline of an organism. does not come without major consequences for society as well as some difficult questions that need answers. The impact on society has as many unknowns and complexities as the scientific research. Some are straightforward: Will the average lifespan continue to rise as it has done for the past century? Is there an upper limit to the current trend? Answering these will depend on finding cures to the big killers – cancers, neurodegenerative disorders, heart disease – and the challenges are immense.

Perhaps a more potent question is not how long we will live, but how high our quality of life will be. Currently, ‘dying of old age’ is preceded by approximately ten years of ill health. What’s more, 30 per cent of deaths in the UK are preceded by dementia, and that number has been predicted by Cambridge researchers to increase to 50 per cent by 2050.

Our increased life expectancy has largely been brought about by medical advances that have

extended life expectancy

20 Focus

removed many acute causes of death. Morbidity and prolonged ill health have become more common with this increased life extension, threatening to create a disparity between long life and good life.

In medical terms, this transition from short, young life to long, degenerative death is referred to as the epidemiological transition.

This is, to a certain extent, why groups like the Methuselah Foundation, which aims to extend healthy human lifespan, have such a strong appeal.

However, the science tells us that this kind of research is still in its infancy. From the study of telomeres we have a better idea of what ageing actually entails on a fundamental level, yet there’s little to say how this can be applied to developing treatments. Those treatments that have been suggested remain speculative and have yet to be demonstrated in practice. Despite this, just as we have to consider what an ageing population means for society today, the question begs to be asked: what if populations ceased to age?

The most obvious effect of a significantly longer lifespan is the population increase and the subsequent strain on our natural resources. Ethical issues also emerge. Advances in ageing technology could cause further disparity between the developed and developing worlds, divided between those for whom mortality is a fact of life and those for whom death is a rare event. Would our perception of death change? It was Robert Winston who said that humanity’s last taboo is in fact death rather than sex.

Would a society in which death is even less common see death as a greater tragedy?

What kind of family relationships could we expect to see were it feasible for siblings to be born generations apart? And if the age range of female fertility is not extended to the same extent Lent 2010

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as lifespan, what effect would this have on people’s choice between career and family? With a longer lifespan it would seem reasonable and feasible for some to seek professional success after having raised a family.

Concerns about life extension and its effects on the workplace were raised in a 2003 paper from the US President’s Council of Bioethics, whose chair at the time, Leon Kass wrote: “The succession of generations would be obstructed by a glut of the able. The old would think less of preparing their replacements, and the young would see before them only layers of their elders blocking the path.”

There is also the question of how elderly people would be treated. In a work environment where older and younger people have the same physical and mental capabilities, would ageism disappear?

And when people were to retire, would they suddenly be subject to ageism? A 2008 review in the journal Age and Ageing indicated that more than six per cent of the older general population reported receiving significant abuse. Given our current poor record of benevolence towards those over 70, could we be trusted with vulnerable members of society whose age can be measured in centuries rather than decades?

As science evolves, the question is clearly becoming less about tackling the causes of death and more about preventing the causes of ageing. As much as we would prefer things to be otherwise, there is still a long way to go and the likely outcome is that the steady increase in average lifespan may reach a plateau, at least in the short term. Biogerontologists like Kirkwood are optimistic, but the foreseeable future presents undeniable challenges.

“I’m very positive about the scope for Lent 2010

understanding the mechanisms,” says Kirkwood, “and I think the ageing program is malleable, but this is really hard science.”

“To take an analogy, if one were to apply the same simplistic thinking to cancer – we know absolutely what happens in cancer, cells divide when they shouldn’t. With that kind of logic it’s really very simple to say how we should cure cancer, but we just need to find ways to activate these mechanisms. That’s what 50 years of cancer research has been about. We’ve made progress, but we haven’t cracked it.”

“My knowledge of the science of ageing urges caution. Ageing is going to be here with us in basically its present form for some years to come.”

The consequences of any major advances in life extension and their effect on society may seem profound. However, it is clear that most scientists do not expect these kinds of advances any time soon. All things considered, perhaps this isn’t a bad thing.

How would a longer healthy lifespan affect the relationship between the generations?

Anders Aufderhorst is a PhD student in the Department of Physics James Birrell is a PhD student at the MRC Mitochondrial Biology Unit Taylor Burns is a Natural Sciences Tripos Part IIA student in Experimental Psychology Alex Jenkin is a Natural Sciences Tripos Part II student in Plant Sciences

Focus 21

Joker, Womaniser... Physicist?

Jake Harris looks at the life behind the science of Richard Feynman little more about scientists than their name and the value of the constant they defined: Boltzmann, Avogadro, Planck. We are forced to generate our own ideas about scientists’ personalities with little basis. People are drawn to a stereotype of successful scientists that alienates them and places them in a different sphere, removed entirely from ‘the real world’. We imagine a man in his own intellectual bubble; wild hair, lab coat and jam-jar-bottomed glasses askew. He’s happy to spend his time alone, scrawling chalk over blackboard walls. Because that’s how you get science done, right? Wrong.

On May 11, 1918, in a small suburb of New York named Far Rockingham, Richard Phillips Feynman was born. He showed academic flair from a young age, begging his teachers to explain concepts that were far too advanced for his peers. He set up a lab in his bedroom, and became renowned in his neighbourhood for fixing radio circuitry. During his teenage years, he devised his own notations to replace the standard for inverse trigonometric functions, which the young Feynman thought were “crazy”.

Clearly, this was no ordinary childhood.

But it is a unique approach to life that makes a great scientist. Feynman was clearly gifted in his ability to analyse and interpret the physical world, but what truly set him apart was a desire to know;

we often learn

ROSIE POWELL-TUCK

Richard Feynman was more than just a scientist

22 Behind the Science

he sought The Pleasure of Finding Things Out (later the title of his book about the Manhattan Project).

This almost childish curiosity remained with Feynman for the rest of his life. Combining this with blistering intelligence and an eye for adventure, Richard Feynman’s life was set to be one of the most incredible of the 20th century.

During his career, Feynman worked on the atomic bomb, was instrumental in the investigation into the Challenger shuttle disaster and ultimately won the Nobel Prize for his contributions to the rapidly developing field of quantum mechanics. Even though these academic achievements were what led to his eminence, they were merely one facet of Feynman’s multidimensional world.

Excitement and adventure pursued Feynman throughout his life, though he did not actively seek them. His enquiring mind and deep thirst for knowledge (and a keen interest in the opposite sex) often led him down strange and incredible paths that were far from academic. When he and his friend were asked back to a hotel by two mysterious women, his friend cried, “What do they want us to go there for?” Feynman replied, “Hell, I don’t know.

But I don’t have to know. It’s just fun, seeing what’s going to happen; it’s an adventure.” Feynman went with them, alone, and found himself at the party of a society for the deaf. Feynman was fascinated by the way the deaf communicated and, like many of his escapades, this led the young scientist to learn a new skill: sign language.

Feynman amassed a formidable range of skills in his lifetime – from life drawing to juggling to bongo drumming. He acted in student plays, performed in Brazilian street festivals and even turned his hand to deciphering Mayan hieroglyphics, making considerable advances in the field. In whatever direction Feynman turned his razor-sharp intelligence, he succeeded. And every skill was accompanied by an incredible story about its acquisition.

However, there was one area where things weren’t so immediately easy. As an undergraduate at MIT, Feynman explained what he described as “the hard stuff” to less academic students in return for advice on how to deal with girls. He felt awkward around them, but this just presented a new puzzle that, unsurprisingly, he overcame. Soon it became just another of his talents; “The only thing in Las Vegas that was fun was meeting showgirls.” Later, he used Lent 2010

Feynman turned his hand to the deciphering of Mayan hieroglyphics (left) and life drawing (below)

a strip club as an office, scrawling his equations on beer mats. One evening, when Feynman was chatting to the Master of Ceremonies at the club, the man told him never to buy a girl a drink until he had made sure, by asking, that she would sleep with him first. Feynman tested this once – successfully – but concluded it was more fun to adopt a more traditional approach.

In later life, Feynman became a renowned teacher.

The series of undergraduate lectures he gave at The California Institute of Technology (CalTech) between 1961 and 1963 have become legendary in the physics community. His exuberant style provided more than education; it was entertainment.

As a result, CalTech physics undergraduates found their lectures crowded with students of other subjects, who had come to see a master at work. The lecture series became a set of books that are still an essential part of a physics student’s library.

Feynman’s unique personality was perhaps best exemplified while he was working on the atomic bomb at Los Alamos during the 1940s. Extremely sensitive military secrets, such as blueprints and information about radioactivity, were held in safes; “These new filing cabinets were an immediate challenge, naturally. I love puzzles.” Feynman worked hard at understanding the locks, going so far as to take apart his own, and spent hours practising the safe-cracking techniques he had developed himself.

He realised that the big safes, where the really important secrets were kept, had the same mechanism as the little ones in the offices, even though they looked more impressive. He opened some with no difficulty, nonchalantly picking the lock on mankind’s biggest secrets. Unfazed, and showing his passion for mischief, he left anonymous notes inside. He hung around to watch the warden go pale when he returned and found the messages. After leaving the warden to stew for a while, Feynman told him what had happened, with fear that he would be angry.

Instead, he took Feynman in a delighted embrace because he was so relieved that the military secrets hadn’t been leaked.

In the semi-autobiographical book Surely You’re Joking, Mr Feynman!, Feynman’s astounding array of stories are recounted verbatim from recorded conversations he had with friend and film producer Lent 2010

Ralph Leighton whilst they played bongos together.

Feynman’s writing style is endearing; his childlike approach to life can seem naïve, but when one takes into account his incredible achievements, it seems difficult to argue with. What is most striking, both in his writing and in the accounts of his friends and family, is that Feynman never displayed a hint of arrogance. Instead, there is a constant air of bemusement at the high esteem in which others held him. It seems clear through his narrative that Feynman’s genius was so intrinsic to his being that he missed it completely.

All scientists can learn something from Feynman: to always approach science with passion, drive and vigour. Never be afraid to pursue a line of enquiry, even if it is for no more reason than interest, and never get down-hearted if you fail to understand something. Constantly seek to look at the same things in different ways, and maintain a clear mind at all times. For most of us, these things don’t come as easily, but at least we know what we’re aiming for.

Feynman died of cancer in 1988 – “I’d hate to die twice, it’s so boring” – but had left his mark on physics, and the world, forever. While his enthusiasm for life was universal, Feynman’s first love was always science, to which his work was an everlasting gift. His genius was summarised by fellow Nobel laureate Hans Bethe; “There are two types of genius. Ordinary geniuses do great things, but they leave you room to believe that you could do the same if only you worked hard enough. Then there are magicians, and you can have no idea how they do it. Feynman was a magician.”

Jake Harris is a first year Natural Sciences Tripos student Nude Sleeping.

Richard Feynamn, 1975

Behind the Science 23

Faith in Science Ian Fyfe gives his perspective on why rejecting religion is bad for science as a scientist, darwinist and atheist,

I may be expected to join with Dawkins and his disciples to worship science and spurn religion. But religion is an integral part of humans as a species and cannot simply be removed. For me, those that preach science while belittling faith neglect the positive influence of religion and are in danger of losing the respect of the public.

Religion is deeply rooted in human history as both a consequence and an element of our evolution.

An overgrown brain provided our hunter-gatherer ancestors with cognitive abilities that allowed our enormous success as a species: ingenuity and imagination were central to survival strategies. Yet the side effect of conscious thought allowed our ancestors to contemplate the world and their own existence within it. The resulting need for explanations – the same need that we possess today – most likely formed the basis for religious belief.

It is easy to imagine how supernatural beliefs emerged in a hunter-gatherer civilisation. Many factors drastically affecting survival were beyond human control: weather, disease, availability of food. Appeals to envisaged rulers of nature may have helped our ancestors feel that they had some influence over their own survival.

Evidence of these practises has been seen at archaeological sites. Cave paintings depict the performance of rituals to communicate with the spiritual world and ensure successful hunting, most notably a 15,000 year-old picture in the Trois-Frères Cave in France. Head dresses found at other sites also suggest that such rituals took place. The first written

HERBERT KRAFT

Cave painting at the Trois-Frères Cave in France, widely interpreted as representing a shaman performing a ritual to communicate with the spiritual world (right)

24 Perspective

accounts of theistic entities, over 4,000 years old, refer to gods of the weather, animals and planets, further evidence that such beliefs originated earlier with hunter-gatherers and became ingrained over hundreds of generations.

For such prominent behaviour to have persisted from so early and for so long, religion must have had a strong benefit for the survival of the species; had it not, natural selection would have ensured that it was not so universal or eradicated it entirely. Ironically, those who worship Darwin and his theory should be more aware of this than anyone. To write off religion as unimportant is surely to dismiss a crucial element of human evolution.

Our predisposition to religious notions means they will not simply vanish. In a 2006 poll conducted in the US by Time magazine, 81 per cent of those asked said that recent scientific advances had not changed their religious views at all. What’s more, 64 per cent said they would not discard a particular religious belief even if science directly disproved it.

So if discrediting religion scientifically will not change religious beliefs, the currently fashionable mixture of logical reasoning and ridicule will not do any better. Whilst the logic may bolster the case against religion, the ridicule will surely undermine the argument. After all, what is ridicule but a demonstration of arrogance, a display that implies the stupidity of others for having an alternative view? The implication of this attitude is that science holds all the answers and that it is where we should look to for all human improvement. But for most, science is of little use when it comes to the emotional, real-world experience of human life.

By all means tell people about science, present them with the logic. But meandering into the territory of openly judging people because of what they believe, and telling people how they should and should not think, gives rise to the accusation that scientists are preaching a religion of their own. Is this an impression that the scientific community wants to convey? Will it encourage public minds to be open when contentious scientific questions are presented to society? Perhaps when reaching out to the public, scientists should concentrate less on pointing out the flaws in religion and more on conveying the richness of life that science can uncover.

Ian Fyfe is a PhD student in the Department of Pharmacology Lent 2010

An Ancestor’s Tool Kathelijne Koops roams the African rainforest to study chimpanzee culture

on African soil as an undergraduate ready for a life-changing experience as I headed into the tropical rainforests of western Africa to study the elusive chimpanzees of the Nimba Mountains in southwest Guinea. Little did I know that six years later, I would have spent the equivalent of two and a half years roaming the Nimba forests and have chosen to focus my PhD on the elementary technology used by chimpanzees.

Elementary technology refers to the use of tools, for example in foraging. Chimpanzees across Africa vary greatly in the types of tools they use to obtain food.

Some groups use stones to crack open nuts, whereas others use twigs to fish for termites. Chimpanzees, like humans, have distinct local cultures that use different types of technology. My research partly tackles the question of how these cultures evolve.

Chimpanzees also use technology for ends other than foraging. All wild chimpanzees build their nests (or beds) in the trees every night by breaking and weaving branches into a sleeping platform. But what is the function of nest building? And why do chimpanzees in Nimba also build nests on the ground? I’m addressing these questions by measuring the environmental factors that influence a chimpanzee’s choice of sleeping location, including climatic conditions, insect densities and nest tree properties.

Studying chimpanzee technology can be challenging because your subjects tend to run away as soon as they spot you. It takes years of persistence and hard work before wild chimpanzees will accept the presence of humans. Each month, I spend 20 days with a team of dedicated local trackers in a small camp at the heart of the forest, hours from the nearest village. My average work day entails ten hours of trudging through mud and negotiating rocky slopes

i first set foot

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while searching for chimpanzees. The days can feel long and hard, especially at the peak of the rainy season when there are daily torrential downpours.

However, wet clothes and tired muscles are instantly forgotten when we encounter the chimpanzees. The first time a young male tolerated our presence and came down from a tree to investigate us was unforgettable. Initially, he was torn between fear and curiosity, approaching but screaming at the same time. Curiosity won over. After the initial excitement, he calmed down and took a nap only ten metres away.

Even if a direct sighting is not possible, information can be gleaned by other methods.

Chimpanzees move around in search of food, leaving behind their tools and nests. These provide a wealth of information. In addition, ecological factors, such as the availability of food (including fruits and insects) can be systematically measured and analysed. It is even possible to obtain information about nest-builders without ever seeing a chimpanzee, for example by collecting hairs from nests and analysing the DNA. Chimpanzees are our closest living relatives and can provide invaluable insights into our own evolutionary history. By unravelling the factors that drive the use of technology by chimpanzees, we may shed light on how and why Homo sapiens became so dependent on tools. However, chimpanzees are critically endangered and have disappeared from numerous countries across Africa. Only urgent efforts will ensure that they don’t disappear before we learn more about them.

Kathelijne Koops is a PhD student in the Department of Biological Anthropology

Kathelijne Koops

Kathelijne Koops

The Nimba research team at the summit of Mount Nimba (right) and an adolescent male chimp named Poni, the first to accept the team’s presence (below)

Away From the Bench 25

A Significant Interaction Cat Davies talks to Nicola Clayton, Professor of Comparative Cognition and Fellow at Clare College, about her collaboration with the Rambert Dance Company

Philip MYNOTT

Professor Nicky Clayton (right)

we are by definition specialists. With sharp skills, wise decision-making and right-placeright-time luck, we find a position within our chosen niche. And so our specialism becomes even more defined, like an ID tag on our careers.

But what happens if we have two specialisms?

The typical route would be to concentrate on one whilst the other nestles in the wings. Nicky Clayton, professor of comparative cognition at the Department of Experimental Psychology and an accomplished dancer, has managed to blend her two passions in her current role as scientific advisor to the Rambert Dance Company.

Nicky’s day job focuses on social and physical cognition in corvids (rooks, jackdaws, and jays), as well as on the memory and executive skills of other bird families and apes. By night she dances, teaching tango and salsa, and still takes the occasional class in ballet and a weekly jazz workout. Her work with Rambert weaves together her previously separate lives into a tailor-made position.

Nicky’s dual roles are evident in her office, where richly coloured dance photographs bookend heavy psychology volumes. As she explains aspects of avian behaviour, she rises to illustrate her points. Within minutes, you can see the scientist as choreographer and the choreographer as scientist. Through talking to Nicky, you see how working at the frontiers of

as academics

y

26 Arts and Reviews

both science and the arts can create something useful, something beautiful, and can highlight parallels that smash the traditional arts versus science dichotomy.

Rambert is not the only dance company to seek the expertise of academics. The British company Random Dance works with Philip Barnard, of the Cognition and Brain Sciences Unit here in Cambridge, on synergies between choreographic processes and knowledge of cognitive neuroscience.

So why should dance companies need scientific advisors? Dance productions draw inspiration from here and there – folk tales and mythology, historical events, great works of literature. Nature is a common theme, and there lies the need for an advisor who can explain precisely how a swan glides around a lake or (with some creative input) how a mouse king does battle.

Rambert’s latest project is The Comedy of Change, inspired by Darwin’s theories of natural and sexual selection. Through a hawk-eyed sensitivity for opportunity and an instant connection with Mark Baldwin, artistic director of the company and choreographer of Comedy, Nicky has become deeply involved with the production. As she talks about the development of the show, she explains how the artistic collaboration differs from the way teamwork unfolds in her scientific life.

“There are a lot more people involved,” she says, indicating the many facets in transforming a creative concept into a full stage production.

Coupled with a more fluid structure than most university research teams, this means that Nicky’s roles are many and varied. From educational outreach, to working with the dancers and animateurs, liaising with financial backers and giving talks at the production, “the work feels a lot more diverse and a lot more outward-facing than typical scientific collaborations.”

Alongside the expected contrasts, there are many shared aspects between the artistic and scientific processes. Nicky points out that both animal cognition and dance share the challenge of conveying beautiful ideas and thoughts in the absence of language. Both Nicky, as professor of comparative cognition, and Baldwin, as world class choreographer, tease this out by capitalising on movement; “The main difference is that my Lent 2010

HUGO GLENDINNING

subjects have feathers and no hands,” Nicky adds.

Where the choreographer deliberates over which movements are appropriate, the professor debates which tests are best for the job in hand. There are also parallels in the relationship between the subjects and the audience; “Choreographers create something for the audience’s pleasure, but it couldn’t possibly work if the dancers weren’t comfortable with the moves. As a scientist, I have to convince the readership that my experiments are well designed and my claims are realistic, but none of that would happen without the cooperation of the birds.”

One of the principal dancers in The Comedy of Change illustrates the overlap with stunning directness; his head and neck movements mimic the courtship dance of one of the six-plumed birds of paradise. In the forests of New Guinea, and now in British theatres, the male clears his dance space of all the leaves, rises up on his toes, and shimmies across the stage. The male with the best dance and the funkiest head movements not only gets the girl, but also the solo.

So how can dry old science ever compete with the arts for space in the public psyche? As a quick measure, a Google search for scientists Colin Blakemore or Jocelyn Bell Burnell throws up about 30,000 websites.

Do the same for Michael Jackson and we get 4,000 times that amount. As much as Blakemore and Bell Burnell are big news in science, they don’t touch the everyday collective consciousness.

What Nicky is really championing is the idea that the arts really can fling open the doors to science.

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This year in Cambridge, we have had Darwinian music, painting, comedy, and even cookery. The Comedy of Change is the latest example of the arts popularising science. I ask Nicky whether audiences come to be educated as well as entertained. Her answer underlines the subtlety with which the production conveys the science; “Only if they want to be. First and foremost, Mark’s beautiful choreography is for the audience’s pleasure, but hopefully there might be a few ideas that might inspire.” Nicky goes on, characteristically drawing biological analogies; “Our aim is not to educate the public about Darwin’s ideas, it’s about sowing a few seeds. If the public wish to let those ideas germinate, then that will inspire them about Darwin.” Clearly, the project is not a scientific mission, but a means of exposing the public to ideas about life on earth.

Eminent professor, self-confessed bird-nerd and committed dancer, Nicky attributes her enviable energy levels to good maternal genes and a supportive husband; “I recharge by dancing. I’m doing something different. My brain isn’t thinking about science, it’s busy concentrating on something else so it gets a good rest and a break from the science.”

As a schoolgirl, Nicky’s reports warned that she “could do very well as long as she doesn’t burn herself out”. It seems unlikely. From blazing trails in academia to burning up dance floors, the researcher and dancer goes on creating. Like nature’s most harmonious symbioses, such ventures between the disciplines strengthen and nourish the other to ensure continued growth and survival.

Dancers in The Comedy of Change (left) and a male Western Parotia Bird of Paradise performing a courtship dance (below)

The Comedy of Change continues its tour of the UK until 30 April 2010 Cat Davies is a PhD student in the Research Centre for English and Applied Linguistics.

Photo courtesy of Tim Laman For more Birds of Paradise photos, go to www.timlaman.com

Arts and Reviews 27

The Nature of the Beast Lindsey Nield traces the contributions and controversies in the history of animal research immense benefit from research involving animals. According to the Royal Society, virtually every medical achievement in the past century has relied on the use of animals in some way.

Today, animal experimentation is used for scientific and medical research only under stringent controls; this has not always been the case.

The first documented use of animals in research can be traced back to Aristotle in ancient Greece. His observations of physiology led him to classify animals into the two groups that we now call vertebrates and invertebrates. In the 2nd century, the Roman physician Galen studied the function of the kidneys and spinal cord. Dissection of human corpses was illegal, so he relied on the vivisection (dissection of a living body) of pigs and monkeys. As scientific research became more commonplace, so did the use of animal experiments, which became mainstream during the 18th and 19th centuries.

In the late 19th century, immunisation was in its infancy. Louis Pasteur was studying diseases, including chicken cholera, when a batch of bacteria spoiled and failed to induce the disease in chickens that were infected with it. Further attempts to infect the same chickens failed because the weakened bacteria had given them immunity, whilst causing only mild symptoms. He tested this as an immunisation

society has gained

wellcome library, london

A physiological demonstration with vivisection of a dog, painted

by Emile-Edouard Mouchy, 1832 (below)

28 History

technique against anthrax in cattle, stimulating wider interest in tackling disease in this way.

Similarly, life-saving organ transplants could not have been developed without animal research.

Dogs and pigs were vital in the development of the techniques, which started with French surgeon Alexis Carrel’s study of rejoining severed nerves. By the 1950s, transplants were routine, but the organs, such as kidneys, hearts and livers, were frequently rejected by the recipient’s body. Immunosuppressive drugs, which are now used after all transplant surgeries, were developed in the 1970s to prevent rejection. Once again, animal tests were vital in this. Kidney transplants alone now save about 2,000 patients a year in the UK. From drugs such as insulin and antibiotics, to surgery and treatments for cancer and HIV, almost every conventional medical treatment that we rely on rests in part on the study of animals. In fact, it is a legal requirement to ensure that new medicines will benefit and not harm human recipients. The importance of appropriate tests is highlighted by the case of the drug thalidomide, which caused defects in limb development in the children of women who took it during pregnancy. Although thalidomide was tested on animals, effects on foetal development were not directly investigated. Rigorous tests must now be carried out before drugs can be sold.

It was once believed that animals felt no pain, so their suffering was not a consideration. However, we now understand not only that they do feel pain, but also that causing test subjects undue stress affects experimental results. With this knowledge, attitudes towards animal testing have changed considerably.

People began to advocate regulation in the early 1800s, leading to The Cruel Treatment of Cattle Act in Britain in 1822. Although not specific to animal testing, it acknowledged poor treatment and was a first step to regulation. Animal testing is directly addressed in both the 1911 Protection of Animals Act and the 1986 Animals (Scientific Procedures) Act. Ethical questions in animal testing have always provoked strong debate and many organisations have arisen to protect animals and question their use for study. The philosophies and tactics of such groups vary, ranging from peaceful demonstrations to physical, sometimes violent action.

The National Anti-Vivisection Society, one of the first such groups, was at the forefront of British news between 1903 and 1910. The Society condemned the vivisection of a brown terrier during a physiology Lent 2010

tagishsimon

lecture at University College London as cruel and unlawful, and caused controversy by building a memorial statue of the dog. The statue was frequently vandalised and clashes known as the ‘Brown Dog Riots’ followed. Tired of the dispute, the council removed the statue and destroyed it. A new one was commissioned in 1985 and resides in Battersea Park.

Anti-vivisection organisations have also targeted individuals. Colin Blakemore, former chief executive of the Medical Research Council, was targeted by animal rights activists whilst working at Oxford University. They reacted violently to his research into child blindness during the 1980s. This involved sewing kittens’ eyelids shut from birth to study the development of their visual cortex, an approach which, according to Blakemore, directly helped to tackle the condition in humans. However, he and his family endured over a decade of abuse, including razor blade-filled letters, bombs sent to his home and physical assault.

Not all protests involve such violence. During the 1990s, a poster campaign showing cruelty in cosmetic testing on rabbits provoked public outrage and led to the ban of such testing in Britain in 1998. The European Union (EU) has since agreed to phase in a total ban of animal testing for cosmetics throughout the EU from 2009 onwards, and a near-total ban on the sale of such products. Such legislation has forced companies to find alternative testing methods, including the use of donated retinas and lab-grown skin cells to test for eye and skin irritation. It is these kinds of alternatives that opponents of animal research want to see used in all experiments.

In another example, Huntingdon Life Sciences, a contract animal testing company, was brought to the brink of collapse by the campaign group Stop Huntingdon Animal Cruelty (SHAC) through largely non-violent means. At the peak of the campaign in 2000, shareholders were named in newspapers and the company’s bank closed its account to distance itself Lent 2010

from the controversy. The company moved its financial centre to America, where greater protection was given to shareholders’ anonymity, and has since recovered financially. This episode directly led to the government taking a firmer line against animal rights extremism.

The police conducted a number of raids against SHAC and seven leading members were found guilty of blackmail.

Such protests have to be taken into consideration when planning for new testing facilities and research institutions. The planned Cambridge Primate Centre was abandoned in 2004 due to such concerns. The additional cost of supplying security against large scale protests and worries over public safety meant planning applications were rejected. However, in 2006, demonstrations against another new facility in Oxford led to the formation of Pro-Test, an organisation in support of animal experimentation.

The group supported the construction by countering the arguments of anti-vivisectionists and attempting to raise public awareness of the benefits of animal research to mankind.

Under current legislation, scientists are required to search for realistic alternatives before they can be licensed for animal tests. They must consider the ‘three Rs’ first defined in 1959; refinement, reduction and replacement. Refinement of the procedures used so that suffering is minimised; reduction in the number of animals to the lowest required for meaningful results; and replacement of experiments on live animals by non-animal alternatives wherever possible.

When confronted with the ethical issues that animal testing presents, it can be easy to overlook the significance it has played in our lives. Modern medicine would not exist without it. Medical research in particular depends on understanding not only the processes of the living body, but also how they interact. Currently, only animal tests are able to capture this complexity. However, in the past 20 years, the number of animals used for testing has been halved, and with the search for alternatives such as lab-grown cells and computer models now a high priority, the number of animal experiments needed will continue to decrease.

The new Brown Dog memorial erected in Battersea Park in 1985 (left)

Lindsey Nield is a PhD student in the Department of Physics

george shuklin

History 29

Computing in the Cloud Fernando Ramos looks to the future of web technology technology promise a style of computing in which flexible and accessible resources are provided as a universal service over the internet. This may revolutionise the way we use computers.

The basic premise of a cloud application is that data is stored online on a remote server instead of on your personal computer. Data is stored ‘in the cloud’ – you may have no idea where it is, but it can be accessed wherever you are in the world, on any device, be that a laptop or a mobile phone.

Many of us have been using cloud applications unknowingly for years; web-based tools such as Hotmail are established examples.

Cloud computing is increasingly being used to deliver services over the internet as well as providing a convenient place to store files.

Companies such as Amazon, Google and Microsoft maintain vast warehouses that hold hundreds of servers that we connect to each time we use these services. They can provide all computing resources that, up to now, we have had to buy and maintain ourselves; servers, storage, software, operating systems, security and anti-virus programs. Instead of having to buy this wide range of essential kit, cloud computing allows us to rent them from big companies. This is changing computing into a

advances in cloud computing

metin seven www.sevensheaven.nl

Many established web resources already rely on cloud technology to provide universal access to users

30 Technology

utility like electricity or water, which allows us to pay only for what we use.

Small companies no longer need large capital for expensive computing facilities since resources that they need may simply be rented from a cloud provider. This has instant appeal to startups, removing the risk of excessive or inadequate provision of computing resources since these can now be provided on demand. A new company can start small, renting few resources in the beginning, and increase its use of the cloud with rising user demand. If the company grows so that more resources are needed, an instant upgrade is available from the cloud provider. This minimises disruption to existing users while maximising growth of the company.

But why would companies such as Google or Amazon want to let other companies use their resources? The answer is that sharing these resources among many users is economically more efficient. Not only must these online giants buy and install the facilities, they must also maintain them. Individual server usage is often as low as 15 per cent, so renting out their unused resources gives cloud providers an important new source of revenue to offset maintenance costs.

Despite the benefits for businesses and society, some see dark clouds on the horizon as concerns loom over security, privacy and control. There is the potential for unauthorised access to proprietary information and for loss of control over sensitive data. Movement of data from one country to another may raise legal issues, while server failures could have serious consequences. Amazon’s S3 cloud service was down for eight hours in July 2008; such a significant outage represented an incredible loss for hundreds of cloud client companies around the world. These issues must be addressed if cloud computing is to succeed.

Nevertheless, the vision of computing as a utility is becoming a reality. Soon we may all be accessing applications in the cloud and using it to rent resources. The internet will once again provide new possibilities for our use of computers, revolutionising the way we use them both at work and at home.

Fernando Ramos is a PhD student in the Department of Engineering Lent 2010

Books Why We Disagree About Climate Change

CUP, 2009, £15.99

GOING BEYOND the typical scope of the debate, Mike Hulme, founding director of the Tyndall Centre for Climate Change Research, presents climate change as a philosophical idea and more than just a physical phenomenon. He begins with a brief history of the debate, focusing on six researchers who built the field. He then systematically presents evidence to demonstrate the factors that influence our view of climate change; debates on economic frameworks, moral duty, risk, and government policies. Hulme tries to underscore the uselessness of dramatising the effects of global warming, all the while posing hefty humanitarian questions about how we will manage global problems.

Overall, the concepts are easy to understand, even as a non-specialist. However, one tenuous link between disagreements over religious beliefs and their effect on the discussion of global warming comes across as a little far-fetched in an otherwise convincing argument.

Why We Disagree About Climate Change provides real insight into how science and society interact. There is a provocative section dealing with the expectations put on science, and what happens when scientific debate occurs openly in society. Likewise, there is an interesting chapter on the problems of communicating controversial issues. These themes make the book applicable to many, if not all, areas of scientific research. JR

Disturbances of the Mind

CUP, 2009, £16.99

DISTURBANCES OF THE MIND is akin to a novel that is hard to put down. The book provides fascinating information on several neurological disorders, both those that are well-known (Parkinson’s, Alzheimer’s, Tourette’s) and others that are less familiar (Bonnet’s, Clerembault’s). Each chapter deals with one syndrome and is self-contained.

But the book doesn’t focus on the symptoms or the biological mechanisms of the disorders.

Instead it tells us the story of how these disorders got their names; the people that were first to notice them, those who actually named them and whether it is justified for these people to have taken the credit. It also discusses the current state of research in each field.

As with any issue relating to the mind, both science and philosophy are involved. To my pleasant surprise, the philosophy is discussed in a clear and succinct way that fits with the narrative of the book. The language is simple, with a target audience of both scientists and the general public. Overall, this book is a must read for anyone with an interest in the history of mind research. SS

Exposed: Ouija, Firewalking, and Other Gibberish “ALL CITIZENS should be aware of the principles of the scientific method […]observation of nature;

Johns Hopkins University Press, 2009, £13.00

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reflection; and experiment”. Thus, using clear-cut examples and basic scientific principles, mixed with wit and sarcasm, Broch provides scientific explanations for the supernatural and exposes the charlatanism behind such practices as dowsing, clairvoyance and telepathy. Although his position is clear on these “heaps of utter nonsense”, he also explains why, from a psychological point of view, people are tempted to believe in the paranormal.

Broch emphasises the importance of using consistent methods throughout studies and illustrates this with a striking example. The US Federal Aviation Administration fired chickens at airplane windshields to assess the hazards of in-flight collisions with birds. In contrast to the original experiment, British engineers found that the chickens crashed through the windshield and smashed the dashboard. Advice from their American colleagues was to defrost the chicken prior to firing.

Little details make a big difference, and it is these subtleties that induce a smirk as Broch deconstructs common mystical phenomena. But he doesn’t just expose the errors of reason behind the metaphysical; he and his colleagues allow mediums and parapsychologists to perform their feats under mutually agreed conditions. Those of a firm scientific orientation are unlikely to find Broch’s conclusions surprising, but his book still offers some great material for conversation! DV

Book Reviews 31

Letters Your questions answered by Dr I M Derisive

ALEX HAHN www.alexhahnillustrator.com

Email your scientific queries to drderisive@bluesci. co.uk

A study has come to my attention which shows that alcohol can protect the male heart from disease. Can I use this as my defence in court?

Boozy Bill Bill, The study was done in Spain. Clearly, therefore, this defence will only stand up if you are also in Spain, or at least have a small amount of Spain in a jar about your person when in court. It is best to claim that protection is maximised by an undefined amount of varying kinds of alcohol – I’d recommend beer, snakebite, tequila and sambuca as your opening gambit. What should also be understood, however, is that anecdotal evidence shows that this same magic cocktail also appears to make you invincible, invisible, and grant you the powers of flight, telepathy and vocal virtuosity. What is clear is that alcohol levels must be maintained, otherwise you risk side effects: depression, headaches, loss of motivation, and despondence at the refusal of your friends to join you on the dance floor...

Dr I.M. Derisive

reflection of inferior genes. Should you seek some comfort, however, you can take solace in the follow-up web study carried out by another organisation, which found only slight correlations. Even if the connection is real, perhaps you shouldn’t give up just yet – with enough effort you may be able to buck the trend as much as your teeth! I’d advise you to prepare for abject failure though, just in case.

Dr I.M. Derisive Is there a scientific explanation behind the success of Jedward? Because there surely isn’t a musical one!

Xena, the X-factor Warrior Xena, You’re absolutely right – the key is in subliminal messaging that was present in the programme itself!

If you look closely, the letter ‘X’ bears a marked resemblance to the tone deaf pair when they are positioned back to back. Notice also that they often wear red, the very colour of the ‘X’! What’s more, if you play the show’s theme tune backwards through a filter, you can clearly hear the voice of Simon Cowell commanding “Vote for the twins – make me some more money”.

Those who possess the gene xfac1 hear this message and feel compelled to vote. Only those who lack the xfac1 gene are immune to these subliminal messages. There is currently no known survival benefit of this gene, although it appears to be surprisingly common.

Dr I.M. Derisive

ALEX HAHN www.alexhahnillustrator.com

I am on the college tennis team and hope one day to make the professional tennis circuit. I have one worry though – I’m not a very attractive guy, everyone says so. Do you think I could still make it?

Shovelface Simon Simon, Recent work by a team in Bristol suggests that if you were attacked by the ugly dog as a child, you have less chance of being an athletic winner – this study established that physical repulsiveness is an ugly 32 Dr Derisive

Lent 2010

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Do you have what it takes to succeed in research?

EPSRC and STFC studentships for PhD study in 2010 The Cavendish is fortunate in having a significant number of EPSRC and a small number of STFC funded studentships available to potential PhD students.

These studentships, which provide full maintenance and fees support, can be awarded to UK students or EU students who have been in the UK for three years. Fees-only awards can be awarded to other EU students. Applicants should have, or be expecting, a first or a good upper second UK four-year undergraduate degree or equivalent.

Please note that these studentships are not available to overseas students.

A wide range of potential projects is available in the broad area of Condensed Matter. Details of projects can be found at www.phy.cam.ac.uk/admissions/graduate/cm_master_project_list.php Details of other opportunities to study at the Cavendish can be found at www.admin.cam.ac.uk/univ/gsprospectus/courses/pcph/cour/ Further details of Graduate Study and of the application process can be found at www.phy.cam.ac.uk/admissions/graduate/ Enquiries should be sent to admissions@phy.cam.ac.uk