Looking at these photos, I started wondering why the moon – whether “super” or not – looks so big when it is near the horizon compared to when it is higher in the sky. A quick look on the internet revealed that I was far from the only one wondering this. In fact, the “Moon Illusion”, as it is termed, has apparently been pondered for centuries. My initial belief, based on my very cursory knowledge of physics, that this phenomenon had something to do with refraction of light through the atmosphere was quickly dispelled by Wikipedia. Rather it seemed that the Moon Illusion was an actual psychological illusion. However, the writers of the page frustratingly left me hanging as to the mechanisms behind the illusion.  So like any good student, I turned to SOLO.

A surprising amount of literature has been conducted on the phenomenon in the past 100 years. In fact, it seems that no-one is completely sure why the phenomenon occurs, and it continues to be studied to this day. Two major theories regarding the Moon Illusion have emerged from the literature. The older of these is called the apparent-distance theory. This theory basically states that we see the moon as larger when it is at the horizon because we perceive the distance to a horizon moon as greater than that to an elevated moon. We know from experience that the horizon is far away, and environmental cues such as buildings or trees getting smaller and converging into the distance accentuate the vast distance to the horizon. However the lack of such cues in the sky makes points in the sky seem closer. Thus although the image of the moon on our retina is always the same size, it seems bigger at the horizon because we perceive it as further away – and we know that the further away things are, the smaller they appear. This takes a bit of thinking to get one’s head around.

The apparent-distance theory: The moon appears big at the horizon because environmental cues accentuate how far away it is (diagram: from http://lasp.colorado.edu)

However, this cannot be the whole story. When you ask people to judge the distance to a horizon moon or an elevated moon, they say that the horizon moon is closer, inconsistent with the apparent-distance theory. Thus a newer theory suggests that the perceived size of the moon depends on the context in which it seen. That is, people do not infer the size of the moon from its perceived distance, but rather the opposite – they use environmental cues to infer the size of the moon, and subsequently calculate its distance (which is why they perceive a horizon moon as closer). So when the moon is at the horizon, it seems large because you compare it to much smaller objects such as trees and houses. When the moon is elevated, however, it is situated in the middle of a dark expanse of sky, and there are no cues with which to compare it. This has been termed the relative-size theory.

The relative-size theory: The moon appears big when it is low because it can be easily compared with objects in the environment (photo: Bob King, from http://astrobob.areavoices.com)

But the relative-size theory alone also appears insufficient to explain the Moon Illusion. When participants view inverted scenes of the moon at the horizon or in the sky, as if they were bending over and looking at the moon between their own legs (go on, try it!), the effect of the Moon Illusion diminishes.  So when viewing these images, participants see the horizon moon as closer in size to the elevated moon, compared to upright images. These images contain all the same information regarding the size of the moon compared to objects in the environment, so the relative-size theory can’t account for this diminished effect. However, turning the image upside-down impairs the ability to judge distance because of the unusual perspective. This implies that these distance judgments are important in the Moon Illusion.

So it seems that we are still not sure exactly why the Moon Illusion occurs.  However, if you are to encounter a scientist out at Port Meadow in the middle of the night, head between legs and staring at the sky, show a litte respect. They are attempting to answer one of the most ancient questions of the science of perception.

It all began with a post-doctoral researcher from Yale University called Patricia Brennan, who was interested in why the duck genitalia was as complex and unusual as it is. Certain species of male duck seemed to have overly extravagant penises; cork-screwed monstrosities that grow to ridiculous lengths when needed. To the researchers it all seemed like such a pointless waste of energy – why bother evolving such complex and bizarre genitalia? Brennan and her team did a variety of tests to show the exact lengths to which male ducks will go to ensure fertilisation, and the anatomical methods females have developed to avoid it. They videoed the eversion of several species of duck penis, if your eyes (and stomach) can take it, check out one of their videos. You’ll never look at Donald Duck in the same way again…

Disgusting bit over, why do the ducks bother developing such complicated and costly genitalia? It all comes down to conflicts of sexual selection. This arises when male and female individuals of a species have differing ideas of what they want out of their ‘relationship’. For ducks, the male simply wants as many offspring as possible. Following the ideas of W.D. Hamilton’s theory of Inclusive Fitness, the more ducklings, the more of Daddy Duck’s genes get passed on to the next generation. Though females want to have plenty of offspring too, the breeding season can bring many an unwelcome Donald to a Daisy duck’s bed chamber and many females find themselves sexually harassed and raped by other males. In fact it is estimated that up to a third of all duck matings are forced; yet only 3% of ducklings produced come from such forced matings.

A coincidence? Of course not. For a female, living in a world with forced matings means having to find a way to avoid bearing the children of these unwanted visitors who are likely to be substandard to her mating criterion. Such strategies are known as ‘cryptic female choice’, a way the female can control the usage of sperm post fertilisation, thereby avoid becoming fertilised by an unattractive male. For ducks, this entails a maze-like oviduct in a complex cork-screw shape, often ornamented with many out-pockets along the way. Such complex anatomy means that, even if a female is forced to mate with a sub-par male, she doesn’t have to be fertilised by him.
However, as evolution has shown many a time, two can play at that game. Whilst females have developed oviducts of increasing complexity, males have responded with longer and more elaborate genitalia themselves, driven by the selection pressure to impregnate the females despite their internal defence mechanisms. The result is a matching set, both driven by the individuals desire to maximise their inclusive fitness through reproduction (or avoiding it with unfit males, in the female’s case). Though the battle of the sexes rages on, examples such as the duck show just how powerful sexual selection can be. Plus just how much weird stuff you can see on youtube…

For those who fancy a look at the study find it here.

Thanks to the sexes’ differential reproductive biology, all things being equal, it behooves men to sow their seeds in as many fields as possible, whereas women benefit most from picking only the most dedicated farmers. But things aren’t always that straightforward. In other words, all males aren’t always on the lookout for a short-term mate. Some seek long-term partners, and they’re the ones that intend to love you tomorrow.

A new study in Evolutionary Psychology reveals that these different motivations direct male’s attention to different female body parts. And with good reason.

The female body and face advertise a great deal of information. How symmetrical her features are and how smooth her skin is, both indicate her overall health and immunity to disease. Additionally, faces give us cues to trustworthiness and honesty, cues that the rest of the body can’t quite convey. To the male mating mind, a trustworthy face means paternity is certain (read: he thinks he has a better shot of his baby actually being his baby, which is mighty important when it comes to evolution). Her face is also a good indicator of a female’s age, which has a large impact on her fertility. But the best clue to fertility is her waist-to-hip ratio.

The authors of the study, a team from The Chinese University of Hong Kong, assert that focusing on the face is about looking forward to the future of a relationship, but ogling the body – the waist in particular – is about immediate rewards. Fertility, after all, is pretty time-sensitive. They asked if male attention could be captured by, distracted by and perhaps even shifted to different areas of a woman’s body based on whether a man was in the short- or long-term mating mood, and indeed it can.

It seems that we have evolved so that our attention is directed where it needs to go. Males looking for long-term loving look to the female face, but guys who aren’t in it for the long haul look to the body. When it comes to finding long-term lover, paying attention to the face helps the romantic males amongst us to be certain that the child that they are looking after is their own. Zooming in on the waist helps other males solve the problem of where to sow those short-term seeds for maximum effectiveness.

This is hardly an earth-shattering result. But it does make possible the following: what one might see looking through male eyes isn’t far off from the visual scope of a predator. That is, while predators had the ability to hone in on their specific prey using heat signals, evolution has allowed human men – like Arnold Schwarzenegger and Jesse “The Body” Ventura, both males who were in the first “Predator” movie  – to non-consciously, automatically focus their visual attention to the bits of female anatomy relevant to the nature of their own hunts…

An equally important role of the Innocence Project is to attempt to prevent wrongful convictions from occurring in the future. The Project estimates that 70% of those wrongfully convicted are the victims of false eyewitness identification, and puts a lot of effort into teaching people how to take steps to reduce the incidence of false identification. To give just one example, when eyewitnesses come in to perform an identification, they are often provided with simultaneous line-ups, where they can see all members of the line-up at once. This can result in the eyewitness choosing the member of the line-up who is the “best fit” – that is, the member who looks most like the perpetrator, even if the actual perpetrator is not even in the line-up. Providing images of members of a line-up sequentially can help prevent these relative judgments from being made. More information is provided in this video produced by the Innocence Project.

There are a number of other ways to improve the techniques used in line-ups, and much research has been conducted in this area (see this paper for a great review). However, understanding why false eyewitness identification occurs also relies on an awareness of the fallibility of memory. We generally think of ourselves as having a good memory for events that occur in our life; indeed, our whole sense of self relies on these memories. Yet time and again studies have shown that our memories are highly malleable. Thus it might not only be that eyewitnesses are making erroneous heuristic judgments, but they may actually have a distorted memory of the events and people involved in the crime.

A couple of now classic studies conducted in the 1970s demonstrated that memory for events can be distorted by providing information after having experienced the event itself, a phenomenon called the “misinformation effect”. In 1974, Loftus and Palmer had participants watch a video of two cars in an accident. Participants were either asked “How fast were the cars going when they smashed into each other?”, or the same question with less emotive verbs such as “contacted” or “bumped”. The experimenters found that participants who were asked the “smashed” question generally gave a higher estimation of the cars’ speed. Moreover, at a follow-up test this group were more likely to erroneously remember seeing broken glass in the film.

In a second study in 1978, Loftus and colleagues got participants to watch slides of a car driving along a road and hitting a pedestrian. Half of the participants were shown the car stopping at a stop sign, and the other half saw it stop at a yield sign (that’s “give way” to us Brits!). Within each group, half of the participants were asked whether another car had passed by when the car was stopped “at the stop sign”, and the other half whether another car had passed when it was stopped “at the yield sign”. Finally, participants were shown one slide with the car at the ‘Stop’ sign and one with the car at the ‘Yield’ sign, and had to choose which they had originally seen. Participants who had been given consistent information (e.g. originally saw the yield sign and were asked about the yield sign) were much more accurate at choosing the correct slide than those who had been given inconsistent information (e.g. saw the yield sign but had been asked about the stop sign). It seems that members of the inconsistent group often had a false memory of which sign they saw, because of the inconsistent verbal information they received.

It is not hard to see how the results of these studies might transfer to real life situations, and it is clear that the misinformation effect could be responsible for some cases of false eyewitness testimony. Just as memories of the car accident were influenced by the phrasing of the question in Loftus and Palmer’s study, the phrasing of questions made by the police or in court could have a profound influence on eyewitness memory, potentially affecting memory for the course of events or even of the appearance of the perpetrator. We should be wary of the use of leading or emotive questions in these situations. Similarly, just as participants’ memories were influenced by the presence of additional, conflicting information in the second study, the presence of additional information after witnessing a crime could affect memory for the incident. Indeed, in the video above, it is suggested that Jennifer Thompson’s memory for her attacker could have been influenced by the long time she spent viewing the picture of the man she was to wrongly identify and comparing him to the other options. The result was that she really did “remember” this man attacking her, even though she had never seen him until after the attack.

These are just two of the hundreds, if not thousands, of studies that have demonstrated how easily memories of events can be altered. There is now a wealth of research on the factors involved in the misinformation effect, as well as other distortions of memory. But what seems most incredible about all this research is that it often seems simple, yet has such profound social implications. Even just a basic knowledge of the science of memory amongst the right people could be the difference between an innocent man’s freedom and his incarceration.

Understanding how the Earth’s climate works is arguably the most complex scientific problem facing us today.  Almost every aspect of our planet influences the climate; ocean circulation, weather patterns, plate tectonics, distribution of life, volcanism, to name but a few. A change in climate could in turn have an impact on all of these aspects. Although progress is being made, not many can claim even a basic understanding of how such a wide variety of factors interact with each other and the climate, and yet it seems everyone has something to say on the matter.

During his talk, Professor Wunsch outlined four key reasons why climate science is so hard for us to grasp.

1)      Confusion between ‘weather’ and ‘climate’

One cold winter is not the harbinger of doom.  Changes in temperature on year to year scales are not indicative of change in climate, however much researches attempt to link them to reduction in sea ice or changes in ocean circulation. It may turn out that this year’s cold spell is the beginning of our descent into a European ice age, but one year is a microscopic blip in the Earth’s climate history. Without careful analysis over extended periods of time (at least tens of years) we must assume that what we see is short term variation in the weather, not a long term shift in the climate.

2)      The human search for patterns

As a species, humans have evolved to understand the world in terms of cause and effect. This has aided us well in our struggle to survive.  However, it has the occasionally problematic side effect that we search for patterns and causality everywhere we look.  The Earth’s climate system is stochastic and cannot be understood in this way. That is to say that whilst there are many factors that can be shown to influence climate, it also has a completely random component.  This means that it must be understood in terms of probabilities and risk, not in absolutes.  Anyone who says “I know that the ice-caps will have melted in 100 years.” is lying, but they can say “I think that based upon the data I have collected there is a significant risk that the ice-caps will have melted in 100 years, and we should therefore do what we can to mitigate that risk.”

3)      Everyone is an ‘expert’

Most people have an opinion about climate change (I know I do!), including some in high profile positions of scientific authority.  The problem comes when they share their opinions as if they are experts on the subject. Everyone from Nobel Prize winning physicists to politicians weigh in on the debate. Unfortunately given the complexity and lack of human understanding of climate dynamics, they are unlikely to be any more qualified than you or I are to speak on the matter.

4)      The media

The general media has earned itself a reputation for over-extrapolation and misrepresentation of science, and particularly of issues relating to climate.  Professor Wunsch was happy to point out that some ‘tabloid journals’ are also culprits of dramatisation, not just the mass media.  Although some of the media do get it right, with a barrage of conflicting information coming at us it is hard to pick out reality from climate fiction.

The single most important fact in the climate debate is that in the geological past the Earth’s climate has been radically different – both far warmer and far colder – than today. Many have taken this as an argument that we have nothing to worry about; the climate changes all the time and our very existence is evidence that the earth can recover.  So why is anyone worried? Firstly, the majority of research indicates that atmospheric CO₂ is increasing at a greater rate than it ever has in the geological past.  Secondly, never before has our planet been occupied by seven billion humans whose future depends on the state of the Earth.

As Professor Wunsch often re-iterated, we do not have a clear picture about what will happen to the climate, even in the next 10 or 20 years.  What we do know is that the rate of the anthropogenic-induced rise in CO₂ levels is unlike anything the planet has experienced since the advent of life, and that the potential risk to us as a species outweighs the costs to us now if we attempt to do something about it.

Although I would not necessarily agree with every point that Carl Wunsch made, I thoroughly enjoyed his talk.  He was un-hypocritical and un-biased in his presentation of the evidence as evidence, and his own opinion as just that. He spoke as a scientist should; he was clear and honest about what can and can’t be drawn from the data, something vitally important in such a controversial topic, where so much is at stake.

A hive usually consists of a single female Queen and thousands of male drones to reproduce with her, all supported by the Queen’s sterile daughters, who act as workers helping to raise their mother’s offspring. But why would an individual choose a life of sterility if natural selection is centred on the idea of getting your genes into the next generation?
The reason workers usually do not produce their own young can be explained by the concepts highlighted by W.D. Hamilton in the 1960s. Hamilton’s rule showed that a social trait such as altruism can evolve if the cost to the individual is outweighed by the benefit to a relative multiplied by the relatedness between the two.

Honeybees operate a haplodiploid sex-determination system, meaning that whilst females are produced by normal sexual reproduction, males develop from unfertilised eggs. This means that though females are diploid with two sets of chromosomes, males only receive half the amount so are haploid. Therefore it is probable that each worker is more related to any one of the queen’s daughters (her sisters) than to offspring the worker herself might produce. Considering the costs associated with reproducing, workers therefore maximise their inclusive fitness (i.e. the amount of their genes they help continue into the next generation) by rearing their sisters instead, rendering themselves sterile.

However, interesting new research from a team lead by Professor Woyciechowski at Jagiellonian University, Poland has shown that a slight loss in relatedness when the Queen Bee is replaced with a new one can lead to workers rebelling against the system and reproducing themselves. When the reigning Queen produces a daughter to replace her as Head of the Colony the workers suffer a switch in the relatedness of the offspring they are expected to help rear. This transition between Queens means workers change from rearing their brothers and sisters to nieces and nephews. The professor explained that “This drop in relatedness causes the old queen’s workers to lay their own eggs.”

The Polish research team tested this observation by splitting up a bee colony; replicating the temporary lack of a Queen that usually occurs after a swarm (when the queen and part of her colony leave the hive to find a new nest site). They compared their observations with the behaviours of the natural swarm and found the same result in both. Before a new Queen had developed the worker larvae themselves grew ovaries in place of the food-producing glands they normally have to nurse the Queen’s young. This ability to switch from nursing to rebel strategy shows that, although honeybees usually rely on an altruistic lifestyle, a slight change in situation can soon turn co-operation into conflict.

To understand why this scanner is an exciting advancement for neuroimaging in Oxford, it is important to understand a bit more about what the MRI scanner does, and what 7 Tesla (T) actually means in terms of imaging.

Many people will be familiar with what MRI is, through personal experience or from the often-embellished world of TV shows such as House. Briefly, it is an imaging technique to visualize internal body structures. MRI can differentiate between soft tissues, so it is often used to image the brain, muscles, and heart. It also has high sensitivity and is non-invasive, which has lead to its position as the most used imaging method in neuroscience.

MRI uses a static magnetic field in combination with radio waves. Firstly, a large magnet aligns all the protons found in water molecules within the body. Radio frequency transmitters are then used to create localized electromagnetic fields, which push some of these protons out of alignment. When the radio transmitters are turned off the displaced protons flip back into alignment, generating a radio signal as they do so. It is this tiny signal that is picked up, and after thousands of repeats forms the detailed image.

Each scanner is defined by the strength of its large magnet. This is because the magnet is the limiting factor on resolution; the stronger the magnet is, the more clarity the image has. Oxford’s new 7T magnet is really strong. To put it in perspective it is about 5 times stronger than the giant magnets in junkyards that can pick up cars and the magnetic field of the earth itself comes in at just 0.00005T.

The majority of scanners used for clinical applications range from 1.5-3T, but scanners used for human research purposes can reach up to 11.7T. The scanners at Oxford are used just for research, and this new 7T scanner is an addition to an existing 3T one. The smaller 3T machine used to be at the cutting edge of research technologies, but as always times have changed and 3T scanners are now common clinical tools. 7T scanners are the new frontier.

Moving up to 7T from 3T has a few key benefits.  As the field strength increases, so does the raw signal of the scans, and the signal-to-noise ratio (SNR) is boosted. This increase is great for images of brain structure because it allows higher spatial resolution and much finer detail. The improvement may allow researchers to locate lesions that were previously too fine to see, as well as signs of neurodegenerative disorders. Functional MRI (fMRI) – the imaging of brain activity as measured by blood flow – may also be improved at higher field strengths. Scanning times can be reduced for certain types of MRI scans at 7T, which is helpful as patients are required to lie still in the scanner.

However, there are challenges to work around when scanning at 7T. Much of the neuroimaging research in recent years has been carried out on 3T scanners and so protocols and equipment in facilities have been developed for the lower field strength. Everything has been optimized for 3T scanners; time, money and effort must now go into adapting research facilities for the new 7T machines. A further complication particularly effects fMRI; the increased sensitivity means better detection of blood flow in the part of the body you are interested in, but it also means that physiological noise is picked up from all sorts of other bodily functions like fluctuations in brain metabolism and cardiac and respiratory variations. Finally, inhomogeneities in both the large magnet field and the radio field become more pronounced in higher fields leading to a greater degree of artefact and distortion in the brain images. Whilst these technical challenges can be tough to resolve, various hardware and software approaches are being developed to deal with the difficulties.

7T is not expected to replace 3T scanners for clinical use and diagnosis any time soon. Rather, it is an additional research tool for specific types of scans that can supplement the existing methods. As engineers race to keep up with the challenges presented by using these new machines we can be excited about the technological advances in their own right, the potential to gain a better understanding of how the brain works and how diseases may affect it, and that Oxford is leading the way.

Though several answers to this question have been suggested, scientists at Georgia Tech University in Atalanta are attempting to find out once and for all, by ‘rewinding the tape of life’ using experimental microbiology. To do this, researchers Eric Gaucher and Betül Arslan used a 500 million year old gene taken from Escherichia coli bacteria, called EF-Tu. The aim was to insert this ancient gene in place of the modern E.coli gene and see how  it ‘evolved’ over numerous generations. Comparing the modern genome and the newly ‘evolved’ sequence could provide valuable information about the course that evolution takes.

Initially the pair observed that bacteria containing the ancient gene grew far more slowly than their modern descendents. However, after having let eight bacterial lines evolve independently for 1000 generations they found that all of the lineages began to grow faster, a clear sign that evolution had occurred within the genome. Suprisingly, the gene thought to be cause of the evolution, EF-Tu, remained unchanged and it was found that it was in fact the genes that interact with EF-Tu that had evolved differently in each lineage. This has further highlighted the importance of gene interaction in protein synthesis; though the genes might be ‘selfish’ it is often forgotten that they rarely act alone.

The initial findings were recently presented at NASA’s Astrobiology Science Conference 2012, held in Atalanta, but the pair continue their work to see what other twists and turns this road of evolution might uncover. Watch this space…

But I’d be wrong.

Little Los Angelos might have nothing to fear from their friendly neighborhood jaguar – he’s pacing back and forth at the zoo, after all – but a new study reveals that they are just as ready to learn and remember which animals can eat them as are the Shuar, who might actually have to worry about becoming something’s lunch. A forthcoming article in Evolution and Human Behavior begins to draw back the curtain on humans’ universal, evolved propensity to learn about dangerous animals.

Evolutionary psychologists – as well as linguists and a host of others – believe that human brains come equipped with hardware that allows them to learn things like grammar, for instance. Learning is of paramount importance for most animals. From the moment of birth, in some cases, animals have to figure out what to attack and what to run from, what to eat and what to avoid, what to mate with and, um…what not to mate with, and so on.

According to the paper’s authors, H. Clark Barrett of The University of California, Los Angeles and The University of Wisconsin’s James Broesch, “learning is clearly one of evolution’s most important solutions to the problem of how to navigate effectively in the world.”

But how to learn what we need to learn is a problem in itself.

Do we kiss frogs until we either take a poison dart to the throat or find a prince – an instance of trial and error learning – or do we take a path that might require less dangerous and/or slimy experimentation?

Natural selection would seem to favor the latter, especially when kissing the wrong frog can end in an early demise. If anything really, natural selection should favor a means of learning that includes features that help us avoid exactly that.

Meet prepared learning. With it, organisms can go out into the world already equipped with learning mechanisms. Mechanisms that are ready to acquire knowledge necessary for surviving and thriving without us having to indulge in so much trial and error. For instance, lab-reared macaques that have never even seen a snake easily learn to fear snakes from other macaques.

This isn’t just a case of fear what that guy over there who looks like me fears. In fact, this readiness to acquire a fear of snakes from a conspecific (a member of the same species) failed to extend to flowers. Why? Dangerous snakes do lurk in macaques’ habitats and likely have done so in the species’ ancestral environments as well. Flowers, well, not so much. They might lurk, but they’re much less likely to cause grievous bodily harm.

Similarly, rats can quickly learn an association between eating a new food and feeling ill. But they aren’t nearly as fast at making the association between bright lights or crazy sounds and nausea. Why so? For similar reasons as macaques acquire snake fears and not flower fears.

Here’s where the “frame problem” comes in. There is a ton information at rats’ paw-tips that they could pay attention to. However 1,995 pounds of that ton of information – including the noises that were blaring right before they they felt ill – is pretty useless knowledge, especially compared to what they ate right before nausea set in. In short, noise hasn’t had a history of causing nausea; food has. Organisms should be focused on the useful knowledge relevant to the problem at hand.

When it comes to learning what to eat, rats will stay away from food that makes them ill, but like macaques they can skip the trial and error in favor of something far safer for the situation: social learning. Rats can smell each other’s breath to glean information about which foods in the environment are safe to eat.

So a monkey doesn’t have to try petting a snake to acquire a fear of them, a rat doesn’t have to try munching on something rancid to acquire a distaste for it…and children, it turns out, don’t have to run screaming from an animal attack to acquire information about what creatures are and aren’t dangerous. All thanks to social learning.

Not getting eaten is kind of a big deal when it comes to evolutionarily important things like surviving at least long enough to reproduce. It would make sense then, if in the domain of social learning, such danger-related information was particularly salient. Children, like rats and macaques, should be able to use social learning to learn what could end their social lives early.

This was what Barrett and Broesch were hoping to find in both Los Angeles and Shuar children: a predisposition for attaining and retaining information related to animal dangerousness.

The team presented a number of children from both areas with 16 photographs of animals – Tasmanian devils, Komodo dragons and the like – that were either safe or dangerous, and carnivorous or herbivorous. In the experimental condition, children were told the name of each animal, its diet and whether it was safe or dangerous. Then the photo-cards were shuffled and the kids were asked to relay the information they’d just received. (In the control condition, children were asked about an animal’s name, diet and dangerousness without having been told the correct answers first. This was in order to rule out the possibility that something other than social learning – like familiarity, for example – could be behind kids’ information retention.) A week later, all the children were asked to again give the name, diet and dangerousness of the animals in the photos.

Overwhelmingly, children learned and remembered information about which animals were dangerous, even a week after the initial, single information session and even as they forgot animals’ names and diets. After training, Shuar children got 88% of dangerous or not questions correct – and 83% a week later – while they only scored 63% and then 53% on carnivore or herbivore questions.

In short, both Los Angelo and Shuar children seem more apt to learn and to retain information about threats. The fact that children from both of these disparate cultures performed rather similarly in this respect underscores the evolved, universal nature of a preferential learning mechanism being in play. (No kidding, I’ll eat light bulbs the next time someone shows me a report of a fatal civet attack on Sunset Boulevard.)

Learning which animals are real threats first hand, via trial and error, would have been a costly way to learn. That knowledge – of whether it can be pet or you should bolt – is important to gain, and it has been throughout our evolution. If this information were stored in the minds of more experienced pals, parents and the like, then that’s a better place to learn it than in the jungle, lip-to-frog, hand-to-civet or even eye-to-eye with a Shih Tsu hungry for flesh.

So without further ado here are five top tips to keep you perky:

1)     If you can’t sleep then stay in bed; you are still doing good things for your body!

With such a busy lifestyle in Oxford, when you are lying in bed awake at night it is common to want to get up and do ‘something useful’ with this time, but actually you should just stay in bed. There are two reasons for this; firstly research has shown that your cardiovascular and musculoskeletal systems simply require rest, rather than cognitive sleep. Lying down in bed, your heart and your muscles get a chance to recover, keeping your body fit and healthy even when you are sleep deprived. Secondly whilst most people can recognise that they have been asleep if they are awoken after about 30seconds, people with insomnia can be awoken after as long as 20minutes and not recognise that they have been sleeping. This could be happening to you if you are in bed, but not if you have wandered off to do something ‘more productive’! So if you can’t sleep, try not to worry too much about it, just relax and remember that you are doing your body a whole lot of good!

2)     Naps are fabulous

If you are struggling to concentrate, but bedtime is hours off, a little nap can do you the world of good. The ‘power-nap’ should generally be kept to less than 20 minutes though, as much longer than this and your body will start to produce hormones that can alter your body clock, effectively giving yourself jetlag without the perk of a holiday! Luckily caffeine takes about 20 minutes to be absorbed by your body, so if you drink a cup of coffee and then rest your head on the desk for 20 minutes, you will have given yourself a built in alarm clock.

3)     Think in pictures before you sleep

It is very common to find it difficult to sleep because of repetitive thought patterns, essentially because you are replaying your day in your head. However it has been shown that an incredibly effective way of reducing this problem is to do an activity that forces you to think in pictures before you go to bed. For instance whilst you are doing a jigsaw your brain is focussed on the picture and shape that you are looking for, and so repetitive thoughts are drowned out. This can be achieved by lots of activities that require concentration and co-ordination, such as jigsaw puzzles, playing an instrument, or personally, I find a couple of games of Tetris unbeatable for clearing my mind!

4)     Waking up at night

Many people wake up in the night with a groan, thinking that their night’s sleep has somehow been voided by this brief voyage into consciousness. However, many scientists actually believe that deep sleep (the first stage of sleep) is more important than REM sleep (the last stage of sleep) and this is because evolutionarily it does not make sense for the body to prioritise the less important stage. This means that if you wake up in the night, when you fall back to sleep you are falling back into the most important stage of sleep, in some ways cheating the system and getting bonus deep sleep! So instead of groaning, next time you wake up in the night, just smile to yourself and be pleased that you have outwitted the night.

5)     Try not to stress about sleep

Finally, stress induces many of the symptoms that we wrongly associate with sleep deprivation through the production of the hormone Cortisol; puffy eyes and a weakened immune system to name but two. However, the less we worry about sleep the fewer of these symptoms we will display. So instead of panicking that we are ten minutes the wrong side of the golden eight-hour rule; just remember that there are no golden rules, just handy hints that you can take or leave depending on what works for you!

Sweet Dreams Oxford.