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WHAT’S ON THIS MONTH?

Mon 3rd 1:05 B37 Biological Sciences (BS) Research Seminar: Dr Ben Evans (McMaster University, Canada), ‘Duplicate gene evolution and expression regulation in polyploid clawed frogs (Xenopus)’ Tue 4th 1:00 2D24 Psychology Department (PD) Talk: Kerry Schofield, ‘Some touch of madness: differentiating between healthy and at-risk schizotypy’ Lunchtime (BS) BioSoc, Film: check email for details Evening (Java) BE Ball hosted by BioSoc and Tubes Wed 5th 4:00 2D2 (PD) External Talks: Professor Marius Usher (Birkbeck - University of London), ‘Neural synchrony, visual grouping and selective attention’ Thurs 6th 5:00 Staff Common Room (BS) Round Table Talks: Amy Chen TBA, Krystina Golabeck, ‘Shouting at the neighbours: cooperative territory defence or selfish advertisement in the group-living pied babbler,’ Dr Steve Soffe TBA Mon 10th 1:05 B37 (BS) Research Seminar: Dr Kerry Franklin (Royal Society University Research Fellow, University of Leicester), ‘Making light of the cold: Light and temperature signal crosstalk in plant environmental adaptation’

Thurs 13th 5:00 Staff Common Room (BS) Round Table Talks: Ruben Heleno, ‘Seed predation and seed dispersal by birds - a new use for food webs,’ Ellie Whittaker (TBA), Prof Keith Edwards, ‘A personal view on how to get money from the BBSRC’

Mon 17th 1:05 B37 (BS) Research Seminar: Dr Mary Cameron (London School of Hygiene & Tropical Medicine), ‘Future measures for house dust mite control’ Tue 18th 1:00 2D24 (PD) Talk: Nick Scott-Samuel ‘Motion matters’ 5:15 Staff Common Room (BS) Workshop in Ecology and Animal Behaviour: Natalie Hempel de Ibarra , (University of Exeter), ‘Colour vision and behaviour in bees’

Tue 11th 1:00 2D24 (PD) Talk: Chris Kent, ‘The relationship between perceptual processes and retrieval processes’ Lunchtime (BS) BioSoc film: check email for details Wed 12th 4:00 2D2 (PD) External Talks: Professor Neil Burgess (University College London), ‘Spatial memory: from neurons to learning and behaviour’

Wed 19th 4:00 2D2 (PD) External Talks: Professor Dave Perrett (St.Andrews), TBA

Missing Link Editorial Team Head of Production: Anna Leon Editor: Ariane Whitehead Assistant Editor: Agata Staniewicz Design Editor: Emma Clark Art Editor: Nadège Laici Secretary and Treasurer: Sophie Morgan Proofreaders: Anita Singh, Sarah Haigh, Angharad Rolfe Johnson, Katy Blatch. Supervisors: Laura Saez, Nick Easton Head of Marketing: Carsten Reinhard Web Designer: Katherine Dallal


The Missing Link Dear Life Scientists, humans can’t help but place on these creatures’ abilities. Some topical debates ensue – such as the examination of whether it is not only economically, but ethically viable to produce bio-fuels. In a time when the importance of developing ways to feed the world and feed our insatiable appetite for energy is paramount, the little known topic of mass wastage is broached. For those naturalists out there, a critical review of Sir David Attenborough’s latest and last BBC series, ‘Life in Cold Blood’ reminds us why we will miss Attenborough so much when he leaves our screens.

Welcome to The Missing Link, March 2008. This issue is packed full of exciting themes from a discussion of green politics to the thermodynamics of lava lamps (this month’s cover feature), and the psychology behind false memories; including, of course, all of our fabulous regulars. This month we also have a guest extended feature of ‘Cockatiels and Cocktails’, where a gripping story of hyena feeding time in Harar, Ethiopia is so eloquently told. And, another new feature appears this month: The Weird and Wonderful – an account outlining the discovery of a new mammal in Tanzania’s Eastern Arc Mountains. I’m also very pleased to have Dr. Arthur Goldsmith of the School of Biological Sciences’ Behavioural Biology doing a new regular in our ‘Comment’ section. His début as a Missing Link columnist is, I hope you will agree, touché. A fantastic piece describes some of the animals to have become famous in the world of animal behaviour, and highlights the anthropomorphic twist of the Theory of Mind, that we as

Of course, there is plenty more to whet your appetites so I won’t keep you any longer from what I promise will be an educational, controversial and, above all, fantastic read. Ariane Editor

Contents

March 2008

Features

Abaracadabra-Abacus Organic Farming vs. bio fuel The tricky question of Tuberculosis and the BCG Where have all the Quaggas gone? Suggestibility Effect Impulsive Minds

Neurological disorders Ever wondered how a lava lamp works? 8 Ker-ching! Money for maths 10 Evolutionary Epistimology 12 It’s all in the past, man: A Teleological 14 account of the content of mental representation.

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2 3 5 11 13 24 26

28 29 30 31 32 33

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15 16 19 20

Regulars News Events BS Research News Living Geen PD Research News Cockatiels and Cocktails Comment: Green Fever

Comment: The Cult of the Individual Weird and Wonderful Reviews TV and Radio Highlights Games In Focus


News and events

News

Kate Weatherall tells us what’s new to science this month Mummy, Mum & Dad? Doug Turnbull and his team in Newcastle have developed a human embryo with three parents in an attempt to prevent women passing on hereditary diseases through their mitochondria. Over one in 5,000 people suffers from such untreatable conditions including fatal liver failure, strokelike episodes, blindness, muscular dystrophy, diabetes and deafness [doi:10.1016/j.bbabio.2004.09.005]. Turnbull successfully transplanted a donor egg with its nucleus removed and the nucleus of a newly fertilised egg inserted, making an embryo with the mitochondrial DNA of the donor egg. Mitochondria contain only 0.0005% of the genetic information in humans, encoding just 37 genes for reproduction of its own proteins. The human embryos developed normally but, due to restrictions on ethical grounds, were killed after 6 days. Similar work on mice however produced healthy adults. This technique, involving the genetic modification of humans, has huge ethical implications, as Josephine Quintavalle of the pro-life group ‘Comment on Reproductive Ethics’ points out – “It is human beings they are experimenting with…we should not be messing with the building blocks of life.” For campaigners who are seeking a cure for these untreatable diseases it may be a glimmer of hope but a long ethical battle is sure to ensue before the procedure reaches the clinics.

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Men get more reward from computer games than women It seems an obvious claim to make but research now officially proves that men get more out of their XBox360 than women. A recent article in the ‘Journal of Psychiatric Research’ shows that the mesocorticolimbic system, the area of the brain responsible for emotions related to reward and addiction, is significantly more active in males than females when playing computer games [doi:10.1016/j.jpsychires.2007.11.010]. Functional magnetic resonance imaging recordings were made from eleven young men and eleven young women as they played a computer game. The male participants showed much more activity as they succeeded, with the three structures within the reward circuit – the nucleus accumbens, amygdala and orbitofrontal cortex – having more influence on each other. So next time you tell your male flatmates they are addicted to computer games, you actually have proof!

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Nadège Laici

Ice shelf collapse not due to climate change alone

When a 500 bn tonne, 656 ft thick, 1,255 sq mile ice shelf in Antarctica broke apart in March 2002, it was seen as a dramatic sign of the effects of global warming. In 1998 the British Antarctic Survey predicted that the ice shelves were in danger but the speed an d severity of the loss of the shelf, known as Larsen B, was shocking. New studies claim that climate change was not the only cause: “A number of other atmospheric, oceanic and glaciological factors are involved” says Professor Neil Glasser of Aberystwyth University. The large amount of meltwater on the shelf before its collapse led many to believe that an increase in atmospheric temperature was to blame; however, other factors such as the location and spacing of fractures on the ice shelf indicate that it had probably been in distress for decades before its final demise.


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News and events

Events

What’s on in and around Bristol this month, by Ariane Whitehead. Fairtrade Fortnight 15th Feb – March 9th There will be a variety of events across Bristol to raise awareness and celebrate Fairtrade Fortnight and there will also be a Fairtrade marketplace in the foyer of the Colston Hall. http://www.fairtrade.org.uk/ Bristol Zoo Gardens 23rd March – 11th May: Night, by the Royal West of England Academy of Arts An exhibition themed around night, with photography, film, drawing, painting and live performance. http://www.rwa.org.uk/index.htm

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Avon Wildlife Trust Thursday 27th March: Behind the scenes at the BBC Natural History Unit Talk by Peter Brownlee, editor of wildlife films. Millennium Hall, Chew Magna, 7.45pm. http://www.avonwildlifetrust.org.uk/ Avon Gorge & Downs Wildlife Project Sunday 9th March: Tree gazing along the Avenue Join Tony Titchen for a Sunday stroll along the tree-lined Avenue, on the Downs and learn how to identify the trees you meet along the way. 2.00pm – 4.00pm, £3.00. http://www.bristolzoo.org.uk/ The Bristol Astronomical Society Observing at Failand on Saturday Nights. Sessions are held every clear Saturday night at their observatory just south of Bristol. http://www.bristolastrosoc.org.uk

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Biology

Abracadabra-Abacus The molecular abacus is an exciting new tool available to molecular scientists. Mehdi Houshmand explores how this instrument will enhance our ability to manipulate tiny particles, and the wider implications of this research. Then and now In terms of the social and physical evolution of man, our ability to create tools is one of the key differences between humans and our animal counterparts. First there was fire, then the wheel – both were and are fundamental to improving quality of life – and then there was the abacus. Thought to be invented as long as 3000 years ago, the abacus is still being used in many parts of the world and has proven the test of time, as one of the key inventions of man. Nevertheless, science, since its birth, has drastically improved, and yet the abacus has returned to the forefront of modern science… though not as we know it. Pioneering research by both the Japanese and IBM’s Department of Research in Switzerland, has seen the development of a new application of Scanning Tunnelling Microscopy (STM), otherwise known as the molecular abacus. STM is a non-optical scanning tool that scans the surface of a sample using a sharp tip, with an electric current flowing between the tip and the sample surface. So when the tip “feels” a current, this means that there’s an electron cloud, and therefore an atom, and by scanning the surface you can create an image down to atomic resolution. However, STM can also be used for

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molecular manipulation and utilised to transport molecules across the surface of a substrate (the material the molecules are on). The molecules used are called bucky balls (C60, carbon atoms arranged into a ball, you may remember from GCSE Chemistry as Buckminsterfullerene), and can be displaced on the surface of a copper (Cu) substrate to create a nanoscale abacus.

“The abacus has returned to the forefront of modern science… though not as we know it.” Tiny molecular balls The bucky balls are evaporated onto the atom clean copper surface in an ultrahigh vacuum (UHV) at room temperature, and then a scan is taken of the appropriate surface area. To keep the bucky ball from moving in a random direction when the STM tip attempts to manipulate it, a step or groove in the copper surface is used. This step is the thickness of an atom (monatomic) and works in

two ways. Firstly, because the bucky ball is weakly bonded to the copper substrate, it means the step acts as a rail for the bucky ball to slide across, constricting its movement to one dimension (1D) – much like a small ball on the rail of an abacus. Secondly, once the bucky ball has been displaced, it is prone to diffusion (the spontaneous and random motion of all atoms and molecules) and the kinks in the step help fix the molecule in place. When the bucky ball is relocated using the STM tip, it can create kinks in the step, and these help keep the molecule stay at the fixed position. This 1D translation of molecules, shows that controlled molecular manipulation is not only possible but with the right tools, quite easily performed. So, with several steps, relating to each rail of an abacus, the molecular abacus can be created and used for simple addition and subtraction. A bright future Obviously, this isn’t the only application of this tool; the possibilities of single molecular manipulation on this scale can be used in anything from data storage to nanomachines. An especially important feature of this work is that the experiment was conducted at room temperature, making it not only far more adaptable as a tool, but also cheaper to operate. However, because of the nature


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Biology

of molecular interactions, technology allows only one ball to be moved with any accuracy at a time; previous attempts to move more than one ball have resulted in the separation between the rows being distorted. The technique is still in its infancy, and has a long way to go before it can be considered as a commercial application. However, a similar experiment using cyclodextrin on a polyrotaxane substrate has shown that this can be conducted without the UHV environment and still at room temperature. The molecular abacus: each of the peaks represents a bucky ball.

UoB Departmental Research News Biological Sciences Ariane Whitehead

Money for new microscope will enhance genetics research

How is this technology going to actually help us? How could this seemingly abstract experiment actually do anything apart from play the muse of a physicist? Well, the answers to both questions aren’t simple, and are really only something time will tell. Nanotechnology is still in its infancy and has a long way to go before it will become commercially available. Nevertheless, with computer chips continuing to obey Moore’s law and becoming ever smaller, technology continues to push the limits of science. The question really becomes: as technology improves allowing us to manipulate the smallest particles… are we able to control things even smaller than this?

Researchers in the School of Biological Sciences have been awarded a quarter of a million pounds for a new microscope through a grant from the Biotechnology and Biological Science Research Council (BBSRC). The confocal laser scanning microscope facility will be used by many laboratories in the department. including the groups of Keith Edwards, Claire Grierson, Alistair Hetherington, Simon Hiscock, and Daniel Robert. Others include the Bailey, Foster, Roberts and Viney labs. In fact, any project in the department that can benefit from high quality images and movies of the smallest visible objects could benefit from the new microscope. When asked about the uses of this microscope Claire Grierson said that “with confocal microscopes we can use light to see inside cells at the highest possible magnifications. By using fluorescent probes like jellyfish fluorescent proteins or dyes that fluoresce, we can capture images and movies of molecules in live cells as they produce and react to signals, change shape, flex, and grow.” The microscope will be able to be used to look at samples that have been prepared in specialist conditions, for example, the development of plant root hairs can be observed without disturbing them. The implications of the new arrival mean that the researchers can “expect the results to tell us many exciting things about how molecular machines assemble, and collect and respond to environmental signals, such as light, sound, and carbon dioxide levels” says Claire Grierson.

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Biology

Organic farming vs. bio-fuel In January 2007 a scandal hit Europe that was largely ignored due to other, more pressing concerns at the time: The return of food mountains. More specifically, it became public knowledge that overproduction by continental farmers had produced stores of 265 million bottles of wine and more than 13 million tonnes of cereal, rice, sugar and milk products. Robert Taylor Williams discusses how we might overcome the issue of enormous wastage and the problem of the land required in order to cultivate bio-fuels. Mass production Food Mountains, the result of the EU Common Agricultural Policy (CAP), have been in decline or completely removed since the 1990s, when the CAP was altered to reduce food production and improve the quality of the food produced. Previously, farmers were paid by the tonne regardless of demand or whether their food was bought, stored or simply left to rot. Organic food, as an enterprise, was introduced as a way for farmers to make a more substantial income without the subsidies they had been receiving from the EU for decades. Producing all that they could would no longer be able to provide more money. They required other means rather than mass production to make an income and, as such, the luxury market for organic farming was born. Standard farmers who generate non-

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organic produce still have great difficulty earning enough to live. Recent TV campaigns over chicken production have highlighted the tiny profits that farmers often make – 2 pence per chicken was a statistic quoted in Hugh Fearnly Whittingstall’s ‘Chicken Run’ program. These farmers are in the firm grip of the supermarket chains and are largely underpaid for their work, without a solution to the modern lower volume demand that organic farming represents. Organic is no better Scientists are highly sceptical of the benefits of organic food. Whilst researching this topic there was not a single study showing that people who eat organically are any healthier, or indeed that organic food was more flavoursome than food of a similar quality rating grown using modern farming methods. Farmers producing normal grain and animal products


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are finding it extremely difficult to make a profit due to the monopoly the supermarkets have as purchasers. All the while, campaigners against bio-fuels are constantly pushing that we cannot produce enough grain to support increased use of bio-petroleum and bio-diesel on a national scale, let alone global, without destroying vast tracts of wilderness to build new farms. One country already has a viable, working bio-fuel industry, and that is Brazil. In response to the oil crisis of the 1970s it began producing bio-ethanol on a massive scale using its vast sugar cane plantations as the source. It is now expanding into producing bio-diesel from soya bean crops. All state buses run on bio-ethanol and most fuel stations have bio-fuel available at a variety of concentrations. The technology is already present to have mixed bio-fuel and traditional fossil fuels. Growing Bio-fuels in the UK All of this presents a solution to me â&#x20AC;&#x201C; we in Europe and England in particular are blessed with beautifully arable land, much of which lies fallow (some of it even subsidised to lie fallow). The old problem of food mountains need not be the waste that it once was. The expansion of the bio-fuel industry could be the break in the monopoly that farmers have needed for years, and the rise in production could lead to a drop in food prices for the consumer without the farmers suffering. In the past England has produced huge quantities of grain, rape seed, sugar-beets and other crops perfect for the production of bio-fuels. Let us use the land to its fullest potential and by doing that save the planet and ourselves. In Europe at least, bio-fuel could be a workable alternative but only if we use everything available to us.

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Biology

The tricky question of Tuberculosis and the In today’s fragile climate, where bacteria easily become resistant to antibiotics, TB rates are on the increase. Sophie Morgan highlights the urgent need for the BCG vaccination to be reinstated in the UK, and the detrimental links found between TB and HIV infection. Scarred Touch the top of your left arm. The chances are that you have a small, flat, circular scar. An incredible guess? No. If you were born before 1990, this will be where the Bacille Calmette Guérin (BCG) vaccination was administered, probably in school. While many people see this as just another routine injection, it is a visual sign that you should be immune to tuberculosis infection. Tuberculosis, or TB, was responsible for around a quarter of all deaths in Europe in the 19th century and many notable figures such as George Orwell, Charlotte Bronte and even Tom Jones have all suffered from it. In the 20th century the number of cases was reduced as living standards improved and antibiotics became available. However, the disease is still widely spread throughout the world and the World Health Organization has currently estimated that one third of the world’s population is infected with the TB bacterium. It is responsible for almost 3% of deaths globally - more than malaria. Due to the fact that the disease can have very few symptoms for months or even years, an infected person can spread the bacteria whenever they cough or sneeze in a public place, without even knowing they are a

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carrier. The symptoms of an active infection can be vague, for example, a cough, feeling tired and a loss of appetite, until serious damage has occurred in the lungs.

“Tuberculosis is a growing problem in countries with high HIV infection rates and TB is in fact the most likely cause of death for HIV positive individuals.” High risk Tuberculosis is a growing problem in countries with high HIV infection rates and TB is in fact the most likely cause of death for HIV positive individuals. HIV has been shown to mask the symptoms of tuberculosis in the early stages – around a third of HIV positive patients have a negative chest X-ray for TB. It also makes it more difficult to treat, as some antiTB drugs can interfere with medication for HIV/AIDS. Compared to someone who does not have the virus, an HIV positive individual is 800 times more likely to have the full blown infectious form of TB.

Antibiotics are the first line of treatment for a TB infection. Someone with infectious tuberculosis requires around eights months to a year of continuous treatment with antibiotics before they are cured of the disease. Nonetheless, antibiotics quickly reduce the ability of the bacterium to spread to other people, meaning that after a few weeks an infected person is no longer at risk of easily transmitting the disease to others. The BCG vaccine has been in use for many decades now, and is no longer considered to be as effective as it once was at providing “herd immunity” (where more than 80% of a population is immune) which can act to protect unvaccinated people by reducing the number of people the organism can infect. The BCG vaccine seems to provide around 60% immunity across the UK. The vaccine, that used to be administered at around the age of fourteen, is no longer routinely given in schools. This is at a time when the number of cases of tuberculosis in the UK is increasing with overcrowding in cities, stressful lifestyles and many people migrating from areas with high TB infection rates. In fact, in the last decade, the number of reported cases has increased by 80% in London alone.


The Missing Link

Biology

BCG – is there an effective alternative?

Control There are certain measures that could ensure a viable alternative to the now redundant BCG vaccine, through careful control of tuberculosis within a population. The need to ensure that people actually complete a course of antibiotics so that resistant strains don’t develop is paramount. Screening migrants from areas with high TB rates before they enter the country and making certain that doctors refer HIV positive people with a chronic cough and fatigue for immediate tuberculosis testing are also ways of helping to reduce the prevalence of this disease. Of course these instances are not always possible in practice, especially when many of those infected don’t experience any symptoms.

teins from the tuberculosis-causing mycobacterium, mean that a good alternative to the BCG vaccine will probably be available in the next decade. Research is currently ongoing in Pohang University, South Korea, led by Drs Youn and Sung, in order to develop a new vaccine to combat Tuberculosis.

Recent advances in vaccination research, such as using certain pro-

The work involves the vaccination of mice with DNA taken from

“The BCG vaccine has been in use for many decades now, and is no longer considered to be as effective as it once was at providing “herd immunity””.

Tuberculosis-causing bacteria [doi:10.1038/sj.gt.3302465]. So far, this has shown promising results in mice, with an effective immune response produced and the results don’t seem to vary with climate, as with the BCG vaccination. However, until a new immunisation program is started this means a huge section of the population will go unvaccinated, as the compulsory BCG vaccine is unlikely to be reinstated before then. This leaves almost an entire generation unvaccinated in this country and while the BCG may not be the best vaccine possible at the moment, it is the only realistic prevention of TB outbreaks that we have. Tuberculosis is a significant problem in Britain and just because it is not as prevalent as in the developing world, does not mean that we can simply ignore it – action to protect our future must be taken.

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Biology Where have all the Quaggas gone?

With extinction levels currently over 100 times greater than they should be, according to trends in fossil records, human impact on our planet’s biodiversity is distressing. Whilst habitat loss and degradation is the key cause of extinction today, Kate Weatherall looks back to how we first started interfering with our ecosystem at ‘Nature Collected’, in Bristol’s City Museum & Art Gallery. In the 18th and 19th Centuries collection of natural artefacts was common, be it to show off to social peers, educate others or through belief that they were of religious significance. ‘Nature Collected’ brings together stories of the collections and the collectors, and the darker consequences of their actions. Male Ruffs were widely collected in the late 1800’s for their beautiful plumage. Genetic variations of this species generate a wide variety of colours and patterns of this plumage, which led collectors to bring the birds to the brink of extinction in attempts to get all the colour variations they could find. Today these waders are found only in the east of England and have recently begun to migrate to the south of the country again in the winter. It was not only collectors at home which endangered species. Museums placed requests with hunters for particular new and mysterious specimens for their collections to increase visitors. The Quagga is a species of zebra which was hunted to extinction for meat and museum displays.

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Native to Cape Province and the Orange Free State in South Africa, the Quagga used to be found in great numbers. The last wild animal was likely to have been shot in the 1870s, with the final Quagga in captivity dying in Artis Magistra Zoo, Amsterdam, in 1883. Unlike Plains Zebras, the characteristic stripes were only found on the front half of their bodies. Modern causes of species extinction are dominated by climate change effects on vulnerable habitats such as mangroves, coral reefs and coastal wetlands. Industrial trawling of fish has also led to endangerment of many fish species. Clearance of forests leads to an obvious reduction in biodiversity, whilst transport of creatures along trade routes more subtly widens distribution of species across the globe. In an attempt to curb this rapid decline in biodiversity, the World Summit on Sustainable Development 2002 set the target to “significantly reduce the rate of loss of biological diversity by 2010”. This is a target that seems unlikely and conflicts with targets to cut world hunger and poverty, which force unsustainable use of

land that drives loss of biodiversity. So what of the Quagga? On discovering that the Quagga was a subspecies of the Plains Zebra and not a separate species, Reinhold Rau began ‘The Quagga Project’ in 1987 to try to bring the Quagga back from extinction by a careful breeding program which hopes to retrieve the genes responsible for their colouration. The most Quagga-like foal to date, “Henry”, was born on the 20th January 2005. Keep up to date with the group’s progress at: www.quagaproject.org. Whilst ‘Nature Collected’ is a small and not too visually striking exhibition, it illustrates some important ethical issues with a personal touch (and there’s a Quagga foot too!). ‘Nature Collected’: A Touring Exhibition will be showing at Bristol Museum and Art Gallery, Queens Road until 31st March 2008.

Recommended Reading Ariane Whitehead If you’d like to experience a first hand account of what it was like to be a zoo collector back in the day, the ‘The Overloaded Ark’ is a charming read. It is written by Gerald Durrell and recounts the times he and his colleague John Yellard spent in the Cameroons in Africa collecting weird and wonderful specimens to take back to the UK. It’s a wonderful and detailed account, with beautiful illustrations of a vast array of intriguing creatures. It certainly transports the reader back to a bygone era and in doing so provides a fascinating insight into the methods and attitudes of the time.


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Biology

Anita Singh reports on a brighter future

make. Each light bulb will save you approximately £60 over its lifetime by using only 20% as much energy as a traditional bulb, which more than makes up for the extra pound or so you might spend on buying them in the first place! Putting that in context, Greenpeace have worked out that if the UK switched to compact fluorescent (CFL) bulbs, we would save 5.1 million tonnes of carbon dioxide in one year – the equivalent of the amount produced by 26 of the lowest-emitting countries combined. The difference in energy usage is all in the way they work: old school bulbs pass a current through a wire, which heats up and produces light. Unsurprisingly it also produces a huge amount of heat, which is why they’re so inefficient. CFLs, on the other hand, pass electricity through a tube of gas, which emits ultra-violet light, which in turn excites a white phosphor coating on the inside of the tube to produce the visible light. We wouldn’t consider using 150-year old technology for anything else so why do we still rely on incandescent bulbs?

One small bulb for you, one huge energy reduction for our planet. Energy saving light bulbs aren’t the newest technology, nor the final solution, but it’s impressive what a difference they

Australia, Cuba, Venezuela and just recently Ireland, Japan and the Philippines have all pledged to ban incandescent bulbs in the near future, and local UK retailers are also showing their support by removing these

Living Green

Marcus Perry

energy-guzzling products from their shelves. Sadly our government is not so committed to the cause. They have, however, proposed a voluntary phase-out of old fashioned bulbs by 2011, but they will still be available to buy after this date, which isn’t exactly ideal. Some myths about energy-saving bulbs: • They are dimmer: This is certainly false – when they say “15 watts” on them instead of “40 watts” they are simply referring to the energy they use, not the brightness. • They take ages to ‘warm up’: While they do have a ‘warming up’ phase, in modern bulbs this is around 3 seconds; this reputation comes from the older models, which today might as well be dinosaurs! • They are ugly and don’t fit most lights: In the past this was very true, but today the bulbs can be found in a myriad of shapes and fittings to fill any hole you can find. So nip down to your local supermarket, electrical shop or hardware haven, save yourself a couple of hundred quid (and the environment a few tonnes of CO2) by kitting our your flat with few eco-friendly bulbs. And next time you’re at a loose end for ten minutes, why not write to you local MP asking for a light bulb ban?

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Psychology

Suggestibility Effect Memory is a complicated and inconsistent process; some people’s memories are better than others, some people remember cars better than faces, and most people begin to lose their memory at some point during their lives. Anita Singh explains why we often seem to remember things that didn’t actually happen to us. Memory is easily corrupted: not only do we forget things, but often we remember things in the wrong order or context, and even things that didn’t happen at all. In some cases this is trivial – childhood memories that someone swears they remember even though they happened when that person was only a year old, or conversations you’re sure you had, but turned out to have been in your head. In other situations misremembering is serious. Standing in the witness stand and remembering something that didn’t happen could have huge consequences, and previous studies have shown that it doesn’t take Jedi mind tricks to change someone’s mind: for example, something as simple as replacing “a broken headlight” with “the broken head

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light” during questioning can make all the difference in how an event is remembered. Children, it has been discovered, are particularly susceptible to this type of suggestion. Theories There are two possible explanations for this suggestibility effect in the literature. The first idea come from trace-strength models, such as the delightfully named ‘Fuzzy Trace Theory’ [doi:10.1006/jecp.1998.2464], where a person distinguishes between the memory of the content of an event, i.e. what actually happened, who was there etc., and memory of the source of the event. The latter type of memory is supposedly forgotten much faster than the former. We end up remembering

Oscar Branson

what happened and to whom, but often forget whether we are remembering what really happened or what someone told us happened. This makes us more susceptible to suggestion and false memories. If this is the case, then the more time between the event and having to remember, the more likely we are to make memory mistakes. The Source-Monitoring Framework, discovered by Johnson, Hashtroudi and Lindsay in 1993, dismisses the claim that memories come all packed up with a handy little tag telling us where and when they were stored. In fact we infer further information from details of the memory. So, for example, you may remember a phone conversation you had with your mum last week and infer from the fact that it was dark and your flat mate was leaving for her evening tap dancing class that it was about 7 o’clock on Tuesday. But if you regularly talk to your mum at around that time on a Tuesday then you may very well confuse the content of the conversation with the one from two weeks ago. According to this theory it is the distinctiveness of the memory that is important, both in time and in situation, so the closer together in time we are given information on the same event, the more likely we are to include misinformation in our recall of the event.


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Psychology False memories Dr. Alexandra Bright-Paul and Dr. Chris Jarrold of the University of Bristol’s Experimental Psychology department have looked into which of these explanations is more plausible. Their research tested the suggestibility effect in 5-year-olds, looking for the first time at the ratio of the intervals between the event and being given misinformation, and this misinformation and a test (being asked to remember). They found that this ratio was actually more important that the absolute time intervals for suggestibility: if the ratio was constant, despite the actual delay being different, suggestibility was the same. This means that being asked to remember a few days after the event or a few weeks after the event shouldn’t affect how much false information is incorporated into memory. What would affect this is if the misinformation is given soon after the event, relative to the time between the misinformation and the remembering. This is similar to the explanation given by the SourceMonitoring Framework which emphasizes discrimination between sources instead of loss of source information over time. This has huge implications in the context of children as witnesses in courts of justice – it was previously thought that a long time delay between event and trial (i.e. time of remembering) would mean there was more of a chance of misremembering. But it appears that it is the time between the event and the first questioning (when suggestions may be made and misinformation given in leading questions) that is important, and that this interval should be longer rather than shorter in comparison to time between first questioning and trial, or statement. It could also mean that if the same >>

<<person questioning the child in the first instance was also questioning them in a court, for example, the likelihood that information fed to the child during questioning would be remembered as genuine memories increases. Research like this is often dismissed as inconsequential and even pernickety but the real life repercussions are potentially critical.

Nadège Laici

Note: the paper in which this research is explained has not yet been published, keep an eye out for it in the next few months for more information.

UoB Departmental Research News Experimental Psychology Sarah Haigh

Children use environmental cues to navigate the world around them Dr Alistair Smith from the Department of Experimental Psychology and colleagues from the Department of Computer Science found that children as young as three years old can navigate their immediate environment when disorientated if they are given environmental cues like landmarks. The experiment consisted of children having to find a specific bucket which contained an object, after they had been spun around with a blindfold (to disorientate the participant). The majority of participants were able to accurately find the object if they had environmental cues to help. Reward awarded for autism work Well done to Dr Liz Pellicano for winning the 2007 Michael Young Prize which is awarded to young researchers for their outstanding research. Her research focused on the development of autism, providing a useful insight for parents and carers who look after children with the condition. Eyewitness testimony Dr Chris Jarrold and Alexandra Bright-Paul investigated children’s memory in reference to eye-witness testimonies, as children are often vulnerable to confusing their memories. The research looked into the causes of the confusion, which is particularly relevant now that children can be used as witnesses in a court of law. Anita Singh reports on this research in more detail on page 12.

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Pharmacology

Impulsive Minds Kate Weatherall explains why it’s sometimes so difficult to just sit still! Impulsive behaviour is a key symptom in a number of psychiatric disorders, including attention deficit hyperactivity disorder (ADHD), schizophrenia and drug addiction. Dysfunction of the 5-hydroxytryptamine (5-HT), or serotinergic, system in the brain has been shown previously to be involved in the formation of impulsivity. Dr. Emma Robinson, from Bristol’s Department of Physiology and Pharmacology, with a group at Cambridge University, has investigated these findings further. ADHD affects 5% of the world’s population, and is characterised by a persistent pattern of inattention, hyperactivity, forgetfulness, poor impulse control and distractibility. The disorder typically presents itself during childhood, however more recently it is beginning to be diagnosed in adults as well. Deficits in impulse control and attention are also key features of schizophrenia and drug abuse. 5-HT is a neurotransmitter found in the wall of the intestine, the blood and the nervous system. It is synthesised by the body itself from the amino acid tryptophan, which is obtained from our diet. There are 7 sub-families of receptor which are activated by the binding of this molecule, 5-HT1 through to 5-HT7. These

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are further classified by a lettering system for example, 5-HT1A. The 5-HT receptors are mainly G-protein coupled receptors, transmembrane proteins containing a “G-protein”, which dissociates on receptor activation to mediate the receptor’s effects. 5-HT2A and 5-HT2C, the receptors studied by Emma Robinson’s group, act to increase the concentration of calcium ions within the cell to activate the cell, thus causing an action potential. Dr Robinson’s team used the 5-Choice Serial Reaction Time Task-test (5CSRTT) [doi:10.1007/ s00213-002-1154-7] to determine the impulsivity of their experimental rats [doi:10.1016/j.neubiorev.2004.09.006]. This test assesses all aspects of impulse control as well as attentional performance, speed of response, and motivation. The rats must scan a horizontal array of 5 holes, each of which contains a light and a sensor that detects if the rat has poked its nose into the hole. When a light is turned on, the rat must poke its nose into the corresponding hole to gain a food reward. If the rat is too impatient, and puts its nose in too fast, no reward is given. This study was carried out to investigate the loci of the effects mediated by the 5-HT2A and 5-HT2C receptors on attention and inhibitory response

control. Micro-infusions of 5-HT2A and 5-HT2C specific blockers were applied to the regions believed to be involved, the nucleus accumbens, the prelimbic cortex and the infralimbic cortex, prior to the 5CSRTT and the impulsivity was then recorded.

Dr Robinson found that the nucleus accumbens was the only brain structure where these pharmacological agents had any effect, with the 5-HT2A antagonist decreasing the impulsive responding and the 5-HT2C antagonist having the opposing effect. These findings indicate that the action of 5-HT within the nucleus accumbens is dependent on the relative level of activation of the 5-HT2A versus the 5-HT2C receptors, and that a change in the relative expression of these two receptors on the cell surface could alter the impulsivity of a subject, potentially causing ADHD.


The Missing Link

Psychology

Neurological disorders: easing the confusion Anyone who studies anything to do with the brain – or more importantly, the brain when it has gone wrong – will surely have had to untangle all the ‘a’ something disorders. In neurobiology, when a patient suffers from a lesion in a specific part of the brain that leads to the inability to do something, for example comprehend language, then it usually has a name. The problem is, they all sound similar and it is difficult to distinguish between them all. Here, I will try and ease your suffering to help them stick a little easier, and for those who are simply interested, I will attempt to enlighten you. Though there are many ‘a’ disorders, the focus here is on aphasia and agnosia. The a-something disorders Aphasia is associated with language – it may be helpful to remember it as ‘a-phrase-ia’. Most language deficits are due to lesions in the left hemisphere. The two best known types are: Broca’s aphasia and Wernicke’s aphasia. Broca’s aphasia occurs when there is a lesion to the inferior frontal lobe and results in the patient loosing the ability to produce language. Wernicke’s aphasia patients loose the ability to comprehend language, which is due to a lesion in the temporal lobe. Aphasia is common in stroke victims and unfortunately many of them become socially isolated as a result of being unable to effectively communicate, but due to successful research in 2008 by Rose and Douglas [doi: 10.1080/02687030600742020], there are various support schemes in place to help patients communicate

via alternative methods.* Alexia is loosing the ability to read words (‘lexia’ from lexicon – the vocabulary of a language) and is commonly associated with Broca’s aphasia, although it has been found on its own when there is a lesion in the left occipital splenium of the corpus callosum (the bit that lies in between the two hemispheres allowing the left and the right hemisphere to ‘talk’). Agraphia can also accompany alexia, which is loosing the ability to write even when other motor skills are intact. Both of these are associated with aphasia and can render it very difficult for the patient to function normally without their regular use of language. What is becoming apparent is that, in a patient suffering from this disorder, words turn into unrecognisable patterns that would normally have meaning and thus the patient is no longer able to copy them. However, it is interesting that these abilities are controlled by different areas of the brain, areas that are usually next to the associated

“It is difficult to understand these disorders from the perspective of a ‘normally functioning’ brain unless you know someone with the disorder.”

Sarah Haigh sensory or motor systems; this means that it is extremely unlikely that a patient will loose all forms of language due to brain trauma.

Sarah Haigh

!

Generally, agnosia is loosing the ability to recognise objects, people, places etc., and is well described in Oliver Sacks’ book ‘Man Who Mistook His Wife for a Hat’, published in 1985. Again there are many types of agnosia (a ‘nose’ is an object so this can be remembered as ‘agnose-ia’), although the majority are due to lesions in the right parietal lobe. Agnosia can be specific to one particular sense e.g. visual agnosia is due to lesions in the occipital and parietal lobes and these patients cannot specifically recognise objects by sight, but can usually identify them via another sense. Certain forms of auditory agnosia prevent the patient from being able to distinguish between non-semantic sounds (those relating to a particular meaning – such as meaning in language), and >>

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Psychology << auditory-verbal and visual-verbal agnosia affect comprehension of language. Perception and recognition Sufferers of visual agnosia usually suffer from prospoagnosia (inability to recognise faces) due to damage in the fusiform gyrus in the temporal lobe. Prospoagnosia (‘prospon’ being Greek for ‘face’) has sparked a lot of research into how we interpret faces as this disorder can vary in its strength and has been seen very mildly in infants. It is now predicted that 2% of the population suffer from mild prospoagnosia without any associated brain trauma. It is also interesting as it adds to the debate of whether our face perception is special compared to our ability to recognise other objects. The last form of agnosia which is particularly interesting is apraxia (‘praxis’ being Greek for ‘act’), which is the inability to complete meaningful actions. There are several types of apraxia, from ocular apraxia (unable to move eyes horizontally) to ideomotor apraxia (unable to orientate hands correctly). Again, agnosia is an interesting disorder because it tells us so much about how the brain has specific areas to deal with certain parts of our environment. It is one of the greatest ironies that science can learn more when things go wrong. It is important to note that patients with these conditions did previously have fully functioning brains and so these disorders are not due to lack of intelligence. It is difficult to understand these disorders from the perspective of a ‘normally functioning’ brain unless you know someone with the disorder – this is especially true of something like propoagnosia, which we take for granted. However, as research deepens into the anatomy of the brain and its behavioural implications, we are slowly learning

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how to help patients get back to living normal lives. *There are local schemes in place to help stroke victims. The North Bristol Speech and Language Therapy team run schemes helping stroke pa

tients with aphasia. If you’re interested in finding out more visit http://www. speech-therapy.org.uk or http://www. stroke.org.uk/document.rm?id=870, which has more detailed information about the centre itself.

Cover Feature

Ever wondered how lava lamps work? Katie Barr explores the role of thermodynamics in the biological world.

It’s the sort of thing you can look at for hours. Brightly lit, undulating bubbles rising and falling in a predictable yet chaotic fashion. As they fall from their peak you can see small, perfectly spherical, bubbles breaking off and cascading down the lamp. The movement is smooth, right down to the base, where bubbles coalesce and continue their cycle slowly, but surely. However rhythmic this evolution is, you can never quite predict the next phase. You can have a good idea about what is going to happen and when, but this is all that you can get. The art of lava Before you stands a simple lava lamp, a concept known to many. However, behind, underneath, inside, this lamp is the interplay between thermodynamics and chaos. The humble lava lamp thus becomes a demonstration of some of the most complex, but im-

portant, areas of physics. I wish to tell you the story of the lava lamp, not the historical one, as that is not what is of interest here, but the physical one. This is an important story. Instead of characters guiding us through the action, we will have the laws of nature. Once we get to know these strange characters we will recognise them everywhere and in some of the most crucial biological processes. I am sure we all know the outline of this story. The light bulb, hidden at the base of the lamp, heats the tube above it. This tube contains water and wax, a very special mixture indeed. As the wax and water heat up, subtle changes occur. It is at this point that the wax begins to form into bubbles and start its journey up the tube, hovering at the top before gliding softly back down to the base. >>


The Missing Link Carole Kenrick

Physics ,

<< Typically people attribute this behaviour to the effect of heat alone. They would say that the wax rises because it is hot and hot things rise, but at the top it cools down, thus eventually falling down. Of course this is true, but it is a gross oversimplification and not at all informative to somebody wishing to grasp enough thermodynamics to understand it in the context of biological systems. A fine balance The manufacturers of lava lamps keep the exact recipes of the solutions contained inside the tube top secret. This is a clue as to how complicated the processes going on inside really are. The waxy solution must have some very precise properties to ebb and flow in the way it does. Firstly, it must be denser than water at room temperature. This is why once the lamp is switched off most of the wax collects at the bottom. Secondly, it must react to temperature increases in just the right way. We all know that as things heat up, they increase in size. The exact increase in size with respect to temperature is dictated by the materials coefficient of thermal expansion. In our case this coefficient must be slightly larger for the wax than it is for the water. This means that the wax expands more than the water for the same rise in temperature, and thus the density of the wax decreases. What results is a substance slightly less dense than water and hence this substance starts to rise. This flow, due to a gradient in density is commonly referred to as a convection current. The wax must not expand too much. If its density were to decrease too much on heating, the wax would just stay at the top of the tube not doing much. For constant movement around the tube the wax must have a very specific coefficient of thermal expansion. >>

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Physics << The physics This gets us somewhere, but in this picture the separation and coalescing of bubbles that gives the lava lamp its hypnotic character is not accounted for. Convection currents account for the larger scale movement of the waxy bubbles, but surface tension must be postulated to account for the smaller details. Surface tension is basically caused by uneven forces at the edges of any medium. Molecules deep inside a medium, in our case wax, are subjected to equal forces on all sides, because they have neighbouring molecules all around them. Molecules on the edge of the wax are subjected to inward forces due to molecular attraction, but with no equalising forces pushing them outwards. The molecules with equal forces on each side have the lowest possible energy state – the amount of energy bound up by the molecules. A general rule in physics is that molecules, or collections of molecules, like to be in the lowest energy state possible. This means that the number of molecules in higher energy states, the ones on the edge, is kept to a minimum. So in order to break this surface the molecules must get some extra energy from somewhere. In this way we are able to consider the effects of surface tension as being similar to the effects of wrapping something up in cling film. The elastic cling film prefers to bend and stretch under pressure, and only breaks when the energy bonding the molecules together is no longer sufficient. Very viscous substances have a high surface tension, more runny substances have a lower surface tension. In the case of the wax floating back to the bottom of the lava lamp, the energy needed to allow smaller bubbles to break off is provided by the heat of the gradually approaching light bulb. Masses of bubbles Let that suffice for the physics of

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surface tension – it has its role to play in biological systems, though it is not as pivotal as the role of thermodynamics. We now understand a little about how convection currents occur and how the exact way they move matter about depends on some very specific properties of the matter in question. This sensitivity is also displayed by biological molecules. Hence why DNA becomes denatured with just a small increase in temperature, though of course in this case thermal expansion doesn’t really enter the picture. By telling the story of the lava lamp, I have given a physical description of convection currents. Convection is only one type of mass transfer, or in English, way of getting from A to B. The other types of mass transfer are diffusion and migration. Migration is the result of a potential difference, or voltage, and is important to consider when studying electrolytes. This relation to electricity shows why electrolyte imbalances are so dangerous to biological organisms. The electrical signals must be ‘just so’ and electrolytes control these.

“The first proteins to form on Earth would not have been in violation of thermodynamics had they been inside an empty box, but they were not.” The other form of mass transfer, diffusion, is also due to thermodynamics. As you may have noticed, convection and migration are caused by differences in density or electric charge. Formally these differences are called gradients and diffusion is also the result of a gradient, though this time the gradient is in the concentration of a particular substance.

This means that the substance is unevenly distributed throughout its container. If energy conditions are favourable the substance will diffuse, or spread itself out until it is equally concentrated everywhere. This is not black magic; it is simply due to random motion. We know that fluids are constantly in motion. Unless there are other forces in action, the molecules in the fluid will zoom about in every possible direction and eventually they will end up evenly spread out. The name for this motion, that appears completely random on the scale of individual particles but predictable for large ensembles of particles, is Brownian motion. This provides possibly the most important link between thermodynamics and biological systems. Indeed, Brownian motion plays a crucial role in the transport of chemicals around cells. It seems then that thermodynamics drives everything to distribute itself evenly – this is why it predicts a cold, dark end to the universe. Eventually everything will be equally spaced, in its most favourable energy state. So it’s natural to ask why, if thermodynamics pushes everything towards uniformity, life has evolved? Sadly I don’t have the answer to that question, but I can explain why thermodynamics seems to be violated on Earth, giving rise to so many varieties of life. The reason is simple. Thermodynamics only truly applies to closed systems, that is systems that cannot interact with the rest of the universe. The first proteins to form on Earth would not have been in violation of thermodynamics had they been inside an empty box, but they were not. They could borrow energy from their surroundings if they needed to, so long as it was made up elsewhere. This is what, for me, makes an otherwise fairly dull aspect of nature truly wondrous. Oh, and I like watching lava lamps too.


The Missing Link

Physics

Ker-ching! Win a cool million dollars for an exact description of blood flow. Ross Lund uncovers the enigma behind the complex Navier-Stokes equations. It is important to understand how our blood flows around our body, through the myriad types of blood vessels and to all of our vital organs. Simply put, without this essential fluid flow, we would be quite dead! So how do we go about describing the flow of blood in the human body? We employ the services of that highly complex mathematical field, fluid dynamics. On a very basic level, the flow of blood can be mathematically “modelled” as a simple viscous fluid flowing through a cylindrical pipe. This gross oversimplification of matters is perhaps the raison d’être of applied mathematics. This model of blood flow follows a simple equation known as Darcy’s Law, which states that the blood flow F, is equal to the change in pressure ΔP, divided by the resistance R, or F = ΔP/R. The resistance here is a generalised parameter depending on the

physical dimensions of the flow. “Ok Ok” you say, “I get it, blood flow can be described by this easy equation that I can use, the medical industry can use etc. etc. Why am I interested in investigating this further?”. Well, to be honest, Darcy’s Law is a pretty awful approximation and there are some obvious problems with it. Many of the most important physical things there have been tied up in that “R”. For example, size of blood vessel, viscosity of blood, speed of flow and so on are all things that not only can vary, but do vary most of the time! Most upsettingly, blood flow in diseased arteries can sometimes be “turbulent”, making it far more difficult to describe. So we need more complicated maths to model blood flow properly, and like most other fluid problems involving turbulence, (for example, the way smoke rises from

a cigarette), the model we need boils down to solving the famous NavierStokes equations.These equations are famous because of their innate insolubility, they cannot be solved directly and can only be vaguely understood through complex numerical methods (even for simple laminar flows, let alone turbulent!!!). The Navier-Stokes equations are in fact one of the “Millennium Prize Problems”. These are seven problems for which the Clay Mathematics Institute is offering $1 million for their solution! So this leaves us firmly wedged up s**t creek without a paddle. Sadly, despite the fact that many, many mathematicians the world over are trying to solve these equations and have been for almost two hundred years, a solution does not appear to be anywhere in sight. To find out more visit: www.claymath.org/millennium/

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Philosophy

Evolutionary Epistemology:

A Philosopher’s new handle on the Theory of Knowledge Natural Selection “The Darwinist says: Do not ask why the mouse runs from its enemy. Species that did not cope with their natural enemies no longer exist. That is why there are only the ones that do. In the same way, I claim that the success of current scientific theories is no miracle… For any scientific theory is born into a life of fierce competition, a jungle red in tooth and claw. Only the successful theories survive – the ones which in fact latched on to actual regularities in nature.” – van Fraassen [B. C. van Frassen (1980), The Scientific Image, Oxford: Oxford University Press, p.40] Who says the principles of evolution theory need to be confined to biology? The philosophers don’t. Impressed by the ingenuity of their Galapagosian cousins, the Athenians have grasped the Darwinian sword, and are sharply incising the flesh of epistemology. So what’s it all about? Can we have a theory of natural selection that transcends the science – non-science boundary? Even within the domain of science, it is hard to imagine the physicists trading in their Schrodinger’s cat for Darwin’s finch, so what do the philosophers think they can do with the theory of evolution?

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It’s not that simple Let’s start with the basics. Evolutionary Epistemology is an attempt to model the development of scientific theories using the principles of Darwinian evolution. It seeks to understand the way in which our theories metamorphose by analogy with the metamorphosing of organisms in biology. The idea is that Darwinian principles can be applied to any domain in which there are ‘entities’ that form lineages or ‘generations’ down which certain attributes are preserved, while others are cast into the fire. Scientific theories, being the sort of things that progress by adaptation, seem to fit the bill. Looking good so far? Maybe not. One immediate concern, as Bradie points out [doi: 10.1007/BF00140962] is that where progression in science results in uniformity or a convergence of theories toward a central underpinning natural law or truth, progression in species evolution results in increasing deviation and diversity. It seems, on this account, that to embrace biology we must ditch the notion of tying things up neatly in some ‘grand unified theory of everything’ in the sciences. Maybe some more convincing is thus in order. An analogy from biology will help to flesh things out. Let’s say, that deep in the tangled

buttercup-studded foliage of the English woodland, there lives a family of red squirrels, and a family of grey squirrels. To our dismay, we notice that the number of red squirrels is decreasing. After some lamentation, we attempt to account for this by appeal to natural selection. We speculate that perhaps the red ones are dying out due to competition from their fellow grey brothers, an overabundance of red squirrel predators or the poor woodland yield of their preferred acorn. Truths We may cast this in a different way by saying that the aim of the process is to have grey squirrels only. The attribute to be eradicated is thus squirrel redness. And the mechanism to achieve this aim, devised by Nature herself, may, for example, be the mass breeding of branch-hopping predators with a special appetite for crimson fur. Similarly, the evolutionary epistemologist may say that the aim of science is convergence on truth. The attribute that he wants to see preserved in our theories is therefore, unsurprisingly, truth. What’s his method for achieving said aim? He [The evolutionary


The Missing Link

Philosophy

Darwinian principles are used in Evolutionary Epistemology to underpin how scientific theories are born, treated and discarded. In an analytical review of this mechanism, Danielle Wills provides analogies to aid our understanding of this fragile philosophical concept and its potential to unify the sciences. epistemologist] has observed the efficiency of Nature’s red-squirrel genocide, and follows suite: He proposes the use of a ‘predator’ to ‘eat up’ the false theories such that after many rounds of mindless bloodshed, only the true theories are around to tell the tale.

“The evolutionary epistemologist has observed the efficiency of Nature’s red-squirrel genocide, and follows suite: He proposes the use of a ‘predator’ to ‘eat up’ the false theories such that after many rounds of mindless bloodshed, only the true theories are around to tell the tale.” Karl Popper, a renowned philosopher of science and proponent of this view, has just the predator in mind: the Conjecture and Refutation approach [Karl Popper (1959), The Logic of Scientific Discovery, New York: Basic Books]. In a nutshell, all

scientific theories are mere conjectures and thus likely to be well off the mark. So, we take our theories and see if they hold out under fire, by ‘exposing them all to the fiercest struggle for survival’, for example, refutation by criticism, damning evidence, and the like. We replace the cinders with fresh theories and repeat the process, and so on until we arrive at something that can survive the flames. This theory or body of theories, we accredit with the attribute of truth. This seems sensible enough. However, during a recent interview, Darrel Rowbottom, a Post-Doctoral Research Associate at Edinburgh University’s School of Physics and Visiting Research Fellow at Bristol University’s Philosophy Department, drew my attention to some glitches in this view. Errors of logic Unfortunately, theories, like squirrels, tend to multiply. If science consisted of a static body of theories for us to pick at like petals of a flower, proceeding one by one till we reach a final verdict, then it is reasonable to think that in time we will arrive at the truth. However, this process of elimination will get us nowhere if the things we are eliminating are being regularly replaced. Worse, we

Artwork by Danielle Wills

are hunting out the true theories by shooting down the false ones, so our procedure is in fact independent of the very theories we claim to be seeking. If, in the woodland analogy, we are bent on finding all the red squirrels in the wood, but our procedure is to isolate the grey ones, it doesn’t take much to pinpoint the logic error. In order for this process to work, there would have to be some causal link between the false theories and the true theories, such that by isolating the false theories we are in fact getting closer to hitting on truth. A possible such causal link is induction, or generalising from observed cases to unobserved cases. This is common practice in the sciences, where we assume that, for example, the laws of physics that we observe in this galaxy are the same in all other galaxies. If, by induction, we assume that a true theory must in some way resemble a false theory, and its only a matter of fine-tuning, then it makes sense to posit that isolating more falsehoods will give us a clearer picture of the truth attribute. Popper, for one, doesn’t believe in induction, but perhaps this would work. Unfortunately, there is another issue here that we have so far overlooked: the notorious human plague of fallibility. >>

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Philosophy << We may think we are rooting out the false theories, but in fact, what we are doing is scrapping the ones that conflict with experience, or appear false on the basis of what we have experienced or learnt so far. In other words, we have no real idea about which theories are false in reality, as there is no universal standard of falsehood to weigh these theories up against. And experience is not reliable. We could, from a distance, mistake a rabbit for a squirrel, or worse, a soiled red squirrel for a grey squirrel. So each time we dispose of a theory, we run the risk of losing a baby with the bathwater. This doesn’t look good for evolutionary epistemology on a Popperian account.

Artwork by Selina Thomas

It’s all in the past, man: A teleological account of the content of mental representation

How do we think about things? Ben Elwyn in another instalment of Philosophy of Life Science features. Just try not to get stuck in a wistful pose too long…

Looking at this page you will see a giant tortoise enjoying the company of another giant tortoise. Or rather, Luckily, there are many other ways to you won’t. What you are seeing is model this idea, some of which may a pictorial representation of a gisurvive these criticisms. One verant tortoise enjoying the company sion, for example, considers scientific of another (the Belgian surrealist theories as ‘parents’, and the predicpainter René Magritte made this tions that we can make from them distinction when he painted a picture as ‘offspring’. Other versions do not of a pipe and wrote underneath it concern themselves with science at “ceci n’est pas une pipe”). I expect all, but look instead at the developthat you would find the above point ment of ideas, human knowledge and facetious and typically ‘pernicketally’ culture within this framework. Those philosophical. I would concur. The who prefer to leave the philosophy resentment probably stems from the out of it do not venture further than fact that you don’t really believe that the organ of thought, the brain, there is a giant tortoise right in front and how it’s influenced by natural of you; the way we describe the belief selection. Furthermore, evolutionary “there’s a tortoise” is just shorthand. epistemologists may disagree about But what if you really were to believe the aim of science, or about which that there was a real-life, breathing attribute is the one to preserve, in the tortoise on the page, would this belief first place. be true? Obviously not, but why? What is it about our thoughts (and One thing is for certain, the philosowords) that they can be made true (or phers are not shy to pick the interdisfalse) by things in the world? ciplinary lock. Perhaps the next port of call is the Einsteinian camp. A GenIn philosophy this dilemma is what eral Theory of Normativity anyone? is known as ‘representation’ or ‘meaning’ (the two terms are almost synonymous) i.e. how our thoughts and language have ‘aboutness’. The problem does not only arise for beliefs that mistake pictures for real things, but also when real things are

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mistaken for other real things, such as seeing a cow and believing that it’s a horse, or, seeing a pipette and thinking it’s a horseradish. To illustrate the issue better, consider a possible solution and why it won’t work. The Crude Causal Theory (CCT), although probably never held by anyone, claims ‘the content of a representational state is whatever typically causes it’. Thus, when I believe that there is a horse in front of me, this belief is about horses because it was caused by a horse. However, the CCT fails here because sometimes (on dark nights or from a distance) we might mistake a cow for a horse. So now our thoughts of horses are about horses-or-cowsfrom-a-distance etc. because they are caused by all these things. This is clearly no good. Jerry Fodor calls this problem ‘the disjunction problem’, where the representational state represents a disjunction of different things. Overcoming the disjunction problem is a primary aim of all theories of content. Without recourse to material dualism (à la Descartes) or other such magical fantasies, philosophers mostly want to offer a naturalistic account of content.


The Missing Link

Philosophy to pair up with a desire. Desires are therefore more basic than beliefs. We can now derive content as follows: Firstly, a belief’s content is its truth condition (what makes it true), and a belief is true if it causes an action, in conjunction with a desire, which fulfils the desires satisfaction condition; and secondly, a desire’s content is its satisfaction conditions.

Attempts at such an account have been made by esteemed philosophers such as Jerry Fodor and Fred Dretske. However, here we shall consider a teleological account. ‘Teleology’ comes from the Greek word telos – meaning “end” (as in, “means to an end”). Teleological accounts therefore seek to explain things in terms of purposes toward ends. Adaptationist thinking in evolutionary biology is full of teleological explanations for example, “wolves have sharp teeth because they need to tear meat” (where there is likely some legitimising story about wolves with sharper teeth eating more meat and therefore having more offspring). A teleological theory of content seeks to explain mental content as having a purpose. On this account, the purpose of each individual mental representation does indeed determine its content. Papineau introduces his teleological account in his book ‘Reality and Representation’. He begins by equating the content of beliefs with their truth conditions, and the content of desires with their satisfaction conditions. In the Humean paradigm that Papineau is working within, beliefs are causally inert unless paired with desires. So in order for the truth of beliefs to make a difference they have

At this stage, however, we are lacking a ‘normatising’ condition of desire satisfaction. That is, a condition that can tell us why something has gone wrong when, for example, we desire warmth and arrive at loud noise. Teleology supplies this normatising condition. At the crux of his account is the claim that beliefs and desires have ‘biological purposes’ and it is these purposes that legitimise talk of truth conditions and satisfaction conditions. For example, the desire for sweet things is biologically supposed to lead one to eat sweet things; therefore eating something bitter will not satisfy the desire for eating something sweet. Such a story, Papineau claims, can be told for many of our mental representations. There are also some things that we do not have the native ability to represent: such as computers, marmite, and other modern items – one might even argue that most of our representations are non-innate. These representations are accounted for by reference to the individual’s learning process: our concepts become fixed if they occur and then lead to advantageous (that is, psychologically rewarding) outcomes. For example, children may learn to associate the concept “blue” with blue things because their teachers reward them when they do so. Teleological accounts have drawn criticism from various philosophers. Fodor is the most outspoken and

does not believe that such accounts have actually managed to solve the disjunction problem. He also complains, citing Gould and Lewontin’s anti-adaptationist paper “The Spandrel’s of San Marco”, that teleological accounts assume the wrong things about natural selection. But see Dennett, Dawkins and Millikan for a defence of adaptationism. A further objection is that of the accidental replica: One night a bolt of thunder hits a swamp out of which arises a human, identical atom to atom, to yourself. According to the teleological theory, this human will not think about anything because he does not have the right sort of evolutionary history (he has none). The objection is, therefore, that while this human might have exactly the same thoughts as you do, yours will be about things and his will not. In reply, Papineau claims that we just have to ignore the intuition that this accidental replica will think about things (Daniel Dennett even suggests the objection is not even worth discussing). An accidental wolf would have sharp teeth but these sharp teeth would not be for tearing meat; they would be for nothing. I believe this reply is sufficient to dismiss the accidental replica objection (not to mention the unlikelihood of its occurrence!). After taking a whistle-stop tour of the difficulties of mental representation, a proposed solution using teleological thinking has been put forward. Hopefully the problems and possible solutions were at least glimpsed as we whizzed by. It is not the easiest problem to worry about because representation is performed so unknowingly, but in philosophy, it is a problem at the root of language and knowledge and is an important platform needed to be built by any physicalist account of the mind.

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Cockatiels and Cocktails And Then There Were None:

James Probert meets the last hyena-man of Harar, Ethiopia The Land Rovers bumped and banged their way along the dirt track. To the left the ruined walls of Harar lay in tumbledown piles, while to the right the sun was sinking below the acacia-dotted horizon. Ever so often along the road there came a fence made out of living cacti, planted so close together that they formed an impenetrable barrier, eight feet high. The farmhouses, made out of wood, plastic, a few rocks and anything else to hand looked, if anything, more rundown and battered than the city’s demolished wall. Eventually the road ran past a larger house made out of chikka: a mixture of mud, straw and cow pat that can be plastered onto a wooden frame where it dries as hard as concrete. The chikka this house was made from and the tin, rather than thatched roof, made it clear that the house belonged to someone who, to the local population at least, was a

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man of standing. The Land Rovers drove past this and pulled in to a patch of bare ground just beyond it. A man strolled out of the house with a bucket in one hand and a stick about a foot long in the other. He was six foot tall with a head that seemed too large for his skinny body. His hair was curled and rose about half a centimetre from his head. The driver of the other Land Rover, Nigel, went up to him and enquired about feeding time. After several minutes of shouting in both English and Amharic, and with the aid of many expansive gestures, he returned to inform us that the man’s name was Mulugeta and that feeding time would be soon. In Ethiopia “soon” could be anytime from five minutes to five hours so we sat on the car bonnets and watched the sun gradually sink behind Mulugeta’s house. As darkness fell Mulugeta wan-

James Probert

dered forward and sat down with his bucket and his stick about five metres in front of the Land Rovers. He pointed at the car and babbled something in Amharic. Five minutes, more babbling in both English and Amharic and much gesticulating later we realised he wanted us to turn the headlights on. We obliged and were just turning round again when the smell first hit us. It was one of the foulest smells imaginable, rotting meat mixed with urine and the smell of wet dog, all magnified so that it made you want to retch. As we wrinkled our noses in disgust the first shape followed the smell out of the darkness. People who watch wildlife programmes from the safety of their couches, I might add, might scoff and say that hyenas are just big dogs and that lions are overgrown kittens. They are not just big dogs. Hellhounds would be a more accurate description. They are not simply large, a Rotweiller is large, and hyenas are at least an extra foot on top of the Rotweiller and twice as wide. On top of this their body slopes downwards, giving them a sinister, hunch-backed appearance, and their fur is matt, dirty and often stained with blood, concealing the natural pattern of sandy coloured fur and darker spots. Hyenas get a bad press because of their ghastly appearance but they actually do more hunting than lions do. Strangely enough this fact was not comforting as more shapes materialised at the edge of our headlights. More and more hyenas arrived


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Cocktail: 1 part Vodka – double shot 2 parts Tomato Juice A pinch of salt Get that down yer neck! (Yuk!) until there were too many to count, circling just out of range of the headlights, their eyes flickering evilly. Finally, a huge female came forward and stood about two feet from Mulugeta, who sat quite happily with his minuscule stick in one hand, his bucket by his side. Mulugeta shifted his position and the huge female leapt away from him and returned to its pacing just outside the pool of the headlights. It’s always amazed me that such a huge creature, easily capable of ripping a man to shreds if it felt like it would leap away at the slightest twitch from a human. Soon enough, the lead female returned to the circle of the headlights and as the rest of the hyenas came to join her, Mulugeta took the lid off his bucket. The stench of rotting meat reached us standing a few metres away and the smell made the hyenas begin to whoop and shrill in excitement. They made a phenomenal range of noises: they whistled, barked, growled, laughed, rumbled and squeaked. Now they came in and formed an almost solid circular wall around Mulugeta. He reached his hand into his bucket and withdrew a sliver of rancid meat that he stuck on the end of his stick, which he then held aloft as he called out a word in Amharic. One of the hyenas came forward, took the meat from the stick and went back to its place in the circle.

This was repeated again, and again. He had named all the hyenas, some thirty in total, and they all came forward as if they were nothing more than well-trained dogs.

“They made a phenomenal range of noises: they whistled, barked, growled, laughed, rumbled and squeaked” He gave lots of meat to one very fat female because he said she was pregnant. She ate all she could and then lost interest and instead started sniffing around the edge of the circle. She wandered over to the hole in the cactus fence that was the entrance to Mulugeta’s compound, where one of Mulugeta’s small children watched the other hyenas. As the pregnant female approached, the child squeaked and fled back inside. The hyena followed and we all yelled a warning at Mulugeta who glanced at the hyena’s tufted tail disappearing inside his compound, waved a hand and yelled “chigger yelem”. From the looks on my family’s faces they certainly did not think that there

was “no problem”, especially as his wife, children and livestock were in the house. Yet to my amazement the hyena soon loped back out at a surprising speed for such a large animal. Behind the hyena appeared the formidable frame of Mulugeta’s wife who threw a rock at the hyena’s retreating form and yelled something in Amharic. The offending hyena skittered away from the rock and trotted back to the circle. The indignant mother lowered her arm and disappeared back inside. Mulugeta had soon abandoned feeding with the stick and hung the meat on his fingers instead again calling the hyenas by name to come and take the meat. Then he held the stick in his mouth so that the hyena would be less than a foot away from his face when it took the meat. All too soon the bucket of meat was gone. We climbed back into the Land Rovers and slammed the doors. Waving goodbye to Mulugeta we drove off back along the dusty road. As we drove my dad said “You know that Mulugeta is the only hyena-man left nowadays? There used to be seventeen.” There was a slight pause whilst we all digested the news and then a further pause while myself, my sister and her two friends looked at each other and wondered who would ask the obvious question. Finally my sister said “What happened to the other sixteen?”.

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Comment Green Fever

A critical review of our political parties’ policies, in the light of renewed urgency in the struggle towards being ‘green’. Hannah Welham

With the five-yearly general elections looming over Westminster, many of us may already be thinking about where to cast our valuable votes on the big day. With a host of campaigns and policies to choose from, many factors may eventually sway our decisions toward different parties. The spin doctors’ current gambit of choice appears to be the environment, with a spate of politicians rushing to jump aboard the fashionable green bandwagon. A

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party which can offer a better future for our environment alongside lucrative education, health and security policies is certainly likely to be attractive. But with each political body clamouring to reach maximum green status, how can we be sure who has the most weight behind their leafy messages? Lackadaisical Labour (www.labour.org.uk) With a series of unpopular errors in their wake, and one of the least charismatic men in Britain at their helm, the Labour party may well have benefited from adding a comprehensive environment plan to their latest manifesto. As it stands, a quick look beyond the bold ‘climate change’ banner donning the party’s website reveals a very scant selection of environmental policies. The site poses questions as to how to effectively encourage environmentally-friendly travel and recycling, without actually providing any answers. To the party’s credit, the recent climate change and energy bills proposed by Brown and his team do at first seem to provide a little more meat to the online proposals. For example, the party has demanded a 60% decline in carbon dioxide emissions by 2050, with a legally binding contract for Britain to meet carbon reduction budgets, the aim being to achieve the world’s first truly low-carbon economy. However, these recommendations have been met with wide criticism, and have even been accompanied by a call from Gordon Brown to build more (environmentally-damaging) nuclear power stations in the coming decade. Conservative Clichés (www.conservatives.com) In 2006, in one of the most famous power plays for the green title to date, Tory leader David Cameron chose to scrap the party’s traditional emblem of a lighted torch for the scribbled logo of a tree. Since then, the MP has hit the headlines for cycling to work and attempting to offset his carbon costs for flights, all in the name of an environmentally-friendly lifestyle. A glance at the party’s website shows just how enthusiastic the Tories are to promote a green campaign, with the endorsement of a “safer and greener” Britain as a favourite mantra. The party does indeed seem to have some more definite goals than Labour for combating climate change. For example, the Tories would like to see a switch from stealth taxes (which currently cost each family in Britain £1,300) to pollution taxes, as part of a new security agenda. Be warned though: if you like facts and figures to back up your government’s claims, the Tories probably aren’t going to be for you, as this is where the numbers seem to stop. The ironic website photo of David Cameron sitting next to a mile-high stack of papers also doesn’t do much to convince browsers of his heartfelt green standing.


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Level-Headed Lib Dems (www.libdems.org.uk) The Liberal Democrats have had a turbulent ride through the turn of the century, with their consecutive leaders invariably dropping like flies. Nick Clegg is now hoping to see the party through the next general election and, by the looks of their manifesto they should stand a good chance with environmentally-friendly voters. Like the Conservatives, the party is also in favour of switching income tax to pollution tax, this time by 4 pence out of every pound. However, this similarity apart, the Lib Dems have managed to construct a more cliché-free, realistic green message for the general public than the Tories have. They claim that Labour’s recent climate change bill is merely a PR move based on outdated science, and would wish instead to see a carbon-neutral Britain by 2050. They would also like to introduce five-year carbon budget targets, and would include research into methane (one of the most potent greenhouse gases) in their plans. They do not however outline what kind of research this may be, so that remains a mystery – perhaps the employment of a viable alternative? In response to Gordon Brown’s blunder over the continued introduction of nuclear power stations, the Lib Dem environment secretary says that Labour’s energy bill is “clearly not the answer to the energy problems that we face today”. The party has begun petitioning amongst the general public for the introduction of a green tax and an end to reliance on nuclear power.

Comment

opinion on these matters are included in the agenda), the manifesto focuses on the development of a sustainable society, based around agriculture, food, the environment, and transport. If elected, the Green Party would aim to achieve a wholly organic and sustainable British farming system, alongside a complete ban on GM foods. The party would also like to initiate more wind, biomass, and solar energy sources, and would introduce fairer flight taxes. Rather than building new roads, the party would channel transport funds into creating new cycle paths, and more efficient train and bus services. The Green Party’s optimism for a better British climate is contagious, but an examination of their policies on non-environmental issues does, unfortunately, leave a lot to be desired.

“They claim that Labour’s recent climate change bill is merely a PR move based on outdated science, and would wish instead to see a carbonneutral Britain by 2050.” Green Party (www.greenparty.org.uk) Of course, no discussion of environmental politics would be complete without recognition of the Green Party. Although not included as a big contender for the general election, the party is without doubt truly green-minded. Rather than concentrating on security and education policies (although the party’s pacifistic

If all this talk of policy and agenda has stirred up your political opinions, why not look into voting in your next local election? See www.electoralcommission.org.uk to get up to date.

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Comment

Photograph by Nadège Laici

The Cult of the Individual: some famous

animals in behavioural and cognitive research, and a final farewell to two of them. Arthur Goldsmith in Japan. Was she an inspirational thinker or just a random chancer? (Imo I mean, not Delia). I fancy we’ll never know.

Most experimental research requires statistical validation from a sample size of the species and quite right and proper too. However, there have been some very famous individuals in behavioural cognitive research that have featured inordinately frequently in their laboratory’s output and have been studied with such mind-boggling intensity that you wonder whether they must have developed cognitive coping strategies of their own, perhaps just to get a break! Sarah the chimp A chimpanzee called Sarah – yes they’ll all have a name, you can be sure – was the first animal, human or otherwise, to be credited with having a ’Theory of Mind,’ courtesy of the first paper announcing the term in 1978. Looking at the subjects listed in many chimpanzee problem-solving papers decades later, Sarah was usually there in the thick of it. She must have been very good at what she did! Until finally, I was told, she became too cantankerous and had to be left out for both hers and the experimenters’ cognitive well-being! Then there was a long line of rigorously pre-programmed (or perhaps I should be diplomatic and say ‘enculturated’) apes drilled with ultimately failed attempts to get them to acquire human language. One spectacularly talented macaque called Imo (even if you live in the wild outdoors you still get a name if you’re a furry biped) showed the rest of her troop how to wash potatoes in the sea and other useful food preparation tips besides. She [Imo the macaque] would have been called Delia, I suppose, if she’d lived in Norfolk, but she didn’t, she lived

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Alex the parrot It is the flighty superstars of the avian world, however, that get the special credits this month, two star research animals that have both died in the last year or so. Alex the African Grey Parrot, enculturated up to his psittacine eyeballs, he really could talk (though it wasn’t a language of course, the words were just drilled in intensive mimetic training). Apparently he could also figure out categories of things in the material world and count up to six. Or maybe not. With what must have been thousands of hours of intensive daily training over more than 25 years, maybe he came up with his own way of categorising what to say to get a nut. Fierce controversy and academic debate accompanied Alex’s every move. Was Alex a special parrot? Again, we’ll never know. He did, however, insert some stylish vocal interjections into the testing sessions: if he wasn’t sure of the answer it would be a hopeful shortcut “wanna nut” and if he was really cheesed off, “wanna go back.” Watch the videos on the web: this parrot is cool, to be sure and now he’ll rest in peace at last. Betty the crow The second sad loss to report is that of Betty, a New Caledonian crow – a feathery biped with attitude is good for a nice name too. There were two crows to start with in the Oxford Laboratory, the other one was called Abel; they could have been A and B I suppose but that wouldn’t be so catchy would it. Now Betty was a sharp mover and could bend a wire just as soon as take a look at the task in hand. Somehow the other crows didn’t quite get it. So was she especially clever, a sharp thinker too? We’ll never know. But Betty does live on, in a surreal sort of way. She’s not only secured her place in the scientific literature, but even her mortal remains continue to appear in lectures announcing her achievements. At one particular Plenary Lecture in Oxford by Alex Kacelnik, at any rate. With Betty initially concealed inconspicuously under a cloth, Alex would reveal the bird with a magician’s flourish, stuffed, mounted and with a suitably bent wire secured in her beak! Ole!


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Weird and Wonderful Hide and Seek

Jenny Whitehair and Sean McGregor introduce a new mammal species recently discovered in the remote African jungle

Unfortunately, no sooner has this species been discovered than it has been placed on the endangered list as it current population is estimated to only just tip into the thousands, and with only two known areas to which it is confined. Whilst the threat of illegal logging is prevalent, fortunately portions of the population exist in a National Park and Nature Reserve, and with this discovery action can be taken to ensure its survival – all hope is not lost.

In the depths of the Eastern Arc Mountains in Tanzania one of Dr. Francesco Rovero’s automatic cameras snapped shut on something quite extraordinary. Dr. Rovero “knew he’d never seen anything quite like it!” The giant elephant shrew, or sengi, is about the size of a small dog making it twice the size of any previously discovered elephant shrews. Given its size and vivid colouration of orange and purple it may seem surprising that this creature has remained hidden from explorers for so long. In fact, it has been 126 years since the last discovery of a new species of this genus has been made. The Udzungwa region, renowned for being one of the densest and most mysterious jungle habitats in

Africa, has kept the secret of this small mammal safe for a long time. So what do we know of this new critter? The sengi is more closely related to the elephant than the shrew and has a specialised ‘feeding trunk’. It uses this trunk to rummage around, hunting in the undergrowth for small insects and bugs.The sengi is monogamous and rears up to three young in a nest crafted by digging a hole in the jungle floor. The hole is then covered with a thick leaf layer, which proves to be a very comfortable, warm shelter from the unforgiving climate of the mountains. But the sengi bears the brunt of nature’s forces silently. Indeed, Dr. F. Rovero reported that peculiarly this animal makes no noise of any sort!

“The giant elephant shrew, or sengi, is about the size of a small dog making it twice the size of any previously discovered elephant shrews.” For more information on the sengi visit: www.sciencedaily.com/ releases/2008/02/080201085759.htm

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Reviews Dr. Tatiana’s Sex Advice to All Creation By Olivia Judson A review by Agata Staniewicz

ten weeks of copulation or a golden potto terrified at the sight of her mate’s spine-covered penis.

“Dear Dr. Tatiana,

Stanford and Oxford graduate Olivia Judson is now an evolutionary biologist at Imperial College of London. Her book, ‘Dr. Tatiana’s Sex Advice to All Creation’ is a collection of letters to the wise Dr. Tatiana from all kind of creatures with strange sexual problems, such as a twenty-sevenyear-old African elephant worrying about his sudden sex obsession and green penis. Her replies are both funny and informative, explaining that the elephant’s situation is completely normal – “a classic case of SINBAD: Single Income, No Babe, Absolutely Desperate,” and female elephants usually prefer much older males. The green penis is also just one of the symptoms of musth, when “the amount of testosterone in male’s body rises up to fifty times the normal level, causing constant dribble of strong-smelling urine.”

“I’m a marine iguana and I’m appalled by the behavior of the young iguanas of today: I keep encountering groups of youths masturbating at me. It’s revolting. I’m sure they didn’t dare act this way in Darwin’s time. How can I make them stop? Disgusted in the Galápagos” People answering questions in the sex-advice column usually don’t encourage (or approve) promiscuity, incest or cannibalism. This might be because they rarely receive questions form a European praying mantis that has discovered she can only enjoy sex after biting off her mate’s head, a stick insect bored to death with

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“Creatures with strange sexual problems, such as a twenty-seven-year-old African elephant worrying about his sudden sex obsession and green penis.” The book certainly is well-researched and full of amazing, surprising and sometimes truly scary facts that will leave you in sheer amazement at the variety of sexual strategies aiding the survival of the species. That, together with the brilliant format of advicefor-the-lovelorn make this “definite guide to the evolutionary biology of sex” a must read for any life scientist.

Attenborough’s swan song is far from cold blooded

Anna Perman reviews David Attenborough’s latest series:

Life in Cold Blood

For many of our generation, David Attenborough’s nature documentaries were what kindled our interest in the natural world. As a child who liked nothing more than reading fiction, it was ‘Life in the Freezer’ that first brought me from the world of the imagination, to the fascinating world around me. And what makes it even better, is knowing that this excitement is something Attenborough shares. In the behind the scenes footage, Attenborough is almost child-like with excitement when he finally sees the smallest chameleon in the world. His passion is why his programmes are so inventive,


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TV and Radio Researched by Agata Staiewicz and Ariane Whitehead engaging and always visually stunning. None more so than his latest and sadly, his last series ‘Life in Cold Blood’. Watching it made me unable to think or say anything but “Wow, that’s amazing!” for a whole hour together. And yet, despite being largely responsible for the enthusiasm of a generation in the natural world – he is often seen by the scientific community as distinctly unhelpful to the progression of work in this field. Although his films are interesting, they do not tell us anything we do not already know. In fact, sometimes he simplifies things down to the point of misrepresentation. At least one Professor in the School of Biological Sciences will have spat out his machine coffee in disgust at the very title of Attenborough’s new series: ‘Life in Cold Blood’. Because ‘cold blood’ is such a misleading name for organisms whose body temperature changes with their environment. And Attenborough probably shouldn’t perpetuate this mistake. But then, ‘Life as an Ectotherm’ just doesn’t have the same ring to it now does it? I think what grates most with those of a scientific mind is not so much what Attenborough misses out, but the overall tone of many of his statements. In ‘Life in Cold Blood’, there are constant references to animals being caring parents, or loving mates. I could go on for pages about how flawed this way of thinking is, but I will be brief. To anthropomorphise animals like this is the language of fiction and has no place in a scientific documentary. Not only is it dangerous to talk in such a way, but really unnecessary. What grips us about these documentaries is not what animals might think or feel, but sheer amazement at what they do and are.

But after picking holes in Attenborough’s scientific credentials to our hearts content, you have to wonder if we aren’t missing the point. Have we become so serious about studying it, that we cannot just sit back and watch the world in all its glory? So I for one plan to unhook the pedant in my brain for just an hour and watch ‘Life in Cold Blood’ in ignorant bliss, just like we used to when we didn’t think we knew better. And first thing Tuesday morning I will go back to my study and cynicism, with a dedication refuelled by that part of me that first watched and marvelled at the wonders of life going on around us. ‘Life in Cold Blood’ is on Mondays at 9.00 on BBC1 and now available on DVD.

The Money Programme – The Great Green Fuel Gamble? BBC 2, Friday 14 March, 7.00-7.30pm www.bbc.co.uk/moneyprogramme

“Like it or not, biofuels are coming to a petrol pump near you soon. They are being touted by governments, oil companies and car manufacturers as a green solution to people’s fuel problems. In two years, five per cent of all the fuel sold in the UK will be biofuel. However, critics say it’s actually environmentally damaging and growing crops such as corn and sugar cane for fuel diverts land from food production. The Money Programme meets the businesses and consumers who have invested in the so-called green fuel and investigates what’s at stake in the battle for a greener future.”

TV Highlights Coast: Severn Estuary to Aberystwyth BBC2, Saturday 1 March, 8pm Life In Cold Blood: Armoured Giants BBC1, Monday 3 March, 9pm. Repeated Sunday Horizon: Are We Alone? BBC 2, Tuesday 4th March, 9-9.50pm Coast: Wales - The Gower, Rockpools and Dylan Thomas BBC2, Wednesday 5th March, 2:45pm The Money Programme: The Great Green Fuel Gamble? BBC2, Friday 14th March, 7-7.30pm Nick Barker’s Weird Creatures 2 Animal Planet, Wednesdays, 9pm; Repeated Thursdays, 2pm Top Dog 2: Animal Planet, Fridays, from 14th March, 8pm Coming up in May: Springwatch

Radio Highlights World on the Move BBC Radio 4, Tuesdays, 11am The Best of Natural History BBC Radio 4, weekly podcast Planet Under Threat: BBC Radio 4, Mondays, 9pm

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Games Crossword ACROSS

!

Fact or Fiction?

3 5 6 7 8 9 11 12 14 16 17 18 19

Discoverers of DNA - Watson and ***** Fly that transmits trypanosomes The genus to which ‘Brewer’s yeast’ belongs A group of giraffes Chemical element needed in the thy- roid gland The smallest mammal in the world (9,3) Component of fungal cell walls *********** Splicing 20 or more amino acids Most abundant atmospheric gas Programmed cell death Eye unique to arthropods Unicellular fungi

DOWN By Tara Macey Five facts, one is false, can you guess which one? • Despite their huge size, Blue Whales cannot swallow an object larger than a beach ball • Birds flying in a V formation have lower heart rates than those flying alone. • Skin is the largest organ of the human body. • Hippopotomonstrosesquippedaliophobia is the fear of talking hippopotamuses. • A group of cockroaches is called an intrusion.

1 2 4 8 10 13 15

‘The ******* of Man’ book by Charles Darwin Perching birds The ‘K’ in K-T extinction The ‘i’ in RNAi Scientists’ favourite worm to study – Caenorhabditis ******* The study of insects Carl ******** the ‘father of modern taxonomy’

Answers: Across: 3. Crick 5. Tsetse . Saccharomyces 7. Tower 8. Iodine 9. Bumblebee bat 11. Chitin 12. Alternative 14. Protein 16. Nitrogen 17. Apoptosis 18. Compound 19. Yeast Down: 1 Descent 2 Passeriforms 4 Cretaceous 8 Interference 10 elegans 13 Entomology 15 Linnaeus Hippopotomonstrosesquippedaliophobia is not actually the fear of a talking hippopotamus but ironically is the fear of long words.

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In Focus

The Missing Link

Send us your photos with a short description and see them here! Submit photos to our Art Editor: Nadège Laici - Nadege.Laici.07@bristol.ac.uk

In focus

“This is Jack - a beautiful, friendly horse I came across in the small heritage village of Lacock, Wiltshire. I took the photograph with my Nikon D80 using the 18-135mm lens. It was on a crisp winter afternoon as the sun was low in the sky - giving it that wonderful light.” Ariane Whitehead

“I took this photo at the Bristol zoo with a canon 30D, this seal was very hungry !” Nadège Laici

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SPONSORS With thanks to...

School of Biological Sciences Psychology Department

Contact Us: Head of Production: Anna Leon - al6230@bristol.ac.uk Editor: Ariane Whitehead - aw6905@bristol.ac.uk Assistant Editor: Agata Staniewicz - as6330@bristol.ac.uk Art Editor: Nadège Laici - Nadege.Laici.07@bristol.ac.uk


UoB Life Sciences Magazine

The

issing Issue 9

ink

March 2008

The Lava Lamp Conundrum how does it work? Also Inside: Dr. Arthur Goldsmith’s début column Organic Farming vs Bio-fuel Memory and Suggestibility James Probert relives his heinous hyena experiences in Cockatiels and Cocktails Hannah Welham discusses ‘green’ politics


Missing Link | March 2008