Posted on 5 January, 2008 by Ed Yong
From an animal’s point of view, the most important things in the world around it are arguably other animals. They provide mates, food, danger and companionship, so as an animal gazes upon its surroundings, it pays for it to be able to accurately discern the movements of other animals. Humans are no exception and new research shows that we are so attuned to biological motion that babies just two days old are drawn to extremely simple abstract animations of walking animals.
Animals move with a restrained fluidity that makes them stand out from inanimate objects. Compared to a speeding train or a falling pencil, animals show far greater flexibility of movement but most are nonetheless constrained by some form of rigid skeleton. That gives our visual system something to latch on to.
In 1973, Swedish scientist Gunnar Johansson demonstrated this to great effect by showing that a few points of light placed at the joints of a moving animal to simulate its gait. When we see these sparse animations, we see them for what they represent almost instantaneously.
Don’t believe me? Just look at this human walker from Nikolaus Troje’s BioMotion Lab website. With just fifteen white dots, you can not only simulate a walking adult, but you can also tell if it’s male or female, happy or sad, nervous or relaxed. Movement is the key to the illusion – any single static frame merely looks like a random collection of unconnected dots. But once they start to move in time, the brain performs an amazing feat of processing that extract the image of a human from the random dots.
Filed under: Animal behaviour, Animal movement, Being human, Child development, Mind and Brain, Neuroscience, Psychology | Tagged: babies, biological motion, innate, instinct, movement, predispositions, science | 2 Comments »
Posted on 19 December, 2007 by Ed Yong
For decades, anthropologists have debated over why pygmies have evolved to be short. Amid theories about their jungle homes and lack of food, new research suggests that we have been looking at the problem from the wrong angle. The diminutive stature of pygmies is not a direct adaptation to their environment, but the side-effect of an evolutionary push to start having children earlier.
Andrea Migliano at the University of Cambridge suggests that pygmies have opted for a ‘live fast, die short’ strategy. Their short lives gives them very limited time as potential parents, and they have adapted by becoming sexually mature at a young age. That puts a brake on their pubescent growth spurts, leaving them with shorter adult heights.
Filed under: Being human, Evolution, Human evolution | Tagged: , body size, height, humans, life history, pygmies, science | 7 Comments »
Posted on 7 December, 2007 by Ed Yong
For all the millions that are poured into electoral campaigns, a voter’s choice can be influenced by the subtlest of signals. Israeli scientists have found that even subliminal exposure to national flags can shift a person’s political views and even who they vote for. They managed to affect the attitudes of volunteers to the Israeli-Palestine conflict by showing them the Israeli flag for just 16 thousandths of a second, barely long enough for the image to consciously register.
These results are stunning – even for people right in the middle of the one of the modern age’s most deep-rooted conflicts, the subconscious sight of a flag drew their sympathies towards the political centre.
Filed under: Being human, Mind and Brain, Psychology | Tagged: flags, Israel, Israeli-Palestine conflict, Palestine, subconscious, subliminal, symbols | 3 Comments »
Posted on 1 October, 2007 by Ed Yong
As a species, we value fair play. We’re like it so much that we’re willing to eschew material gains in order to punish cheaters who behave unjustly. Psychological games have set these maxims in stone, but new research shows us for the first time, that this sense of justice is, to a large extent, influenced by our genes.
When it comes to demonstating our innate preference for fair play, psychologists turn to the ‘Ultimatum Game‘, where two players bargain over a pot of money. The ‘proposer’ suggests how the money should be divided and the ‘receiver’ can accept of refuse the deal. If they refuse, neither player gets anything and there is no room for negotiation. In a completely rational setting, the proposer should offer the receiver as little as possible, and the receiver should take it – after all, a very little money is better than none at all.
Of course, that’s not what happens. Receivers typically abhor unfair offers and would rather that both parties receive no money than accept a patronisingly tiny amount. Across most Western countries, proposers usually offer the receivers something between 40% and 50% of the takings. Any offers under 10% are almost always rejected.
The uniformity of responses across Western countries suggests that culture has a strong effect on how people play the game, but until now, no one had looked to see how strongly genes asserted their influence. Bjorn Wallace and colleagues from the Stockholm School of Economics decided to do just that, and they used the classic experiment for working out heritability – the twin study.
Filed under: Being human, Mind and Brain, Personality traits, Psychology | Tagged: behaviour, Co-operation, economics, genes, heritability, justice, twin studies, ultimatum game, unfairness | 2 Comments »
Posted on 21 September, 2007 by Ed Yong
Everybody, apparently, needs good neighbours, but in many parts of the world, your neighbours can be your worst enemy. In the past century, more than 100 million people have lost their lives to violent conflicts. Most of these were fought between groups of people living physically side by side, but separated by culture or ethnicity.
Now, May Lim and colleagues from the New England Complex Systems Institute have developed a mathematical model that can predict where such conflicts by looking at how different groups are spread out in a given area.
According to their research, violence is most likely to erupt in areas with poorly-defined boundaries between large and culturally different groups. Their model predicted areas of ethnic violence in both India and Yugoslavia with uncanny accuracy, and Lim hopes that it will help policymakers to look at the problem of violent conflicts with a scientific eye.
Filed under: Being human, Culture, Psychology, Science & society | Tagged: conflict, cultural violence, ethnic violence, population structures, violence | 2 Comments »
Posted on 19 September, 2007 by Ed Yong
About 11% of the British population is currently left-handed. But that wasn’t always the case. Among people born in 1900, the proportion of lefties was just 3%.
Chris McManus and Alex Hartigan from University College London worked this out with the help of old films made at the turn of the 19th century and recently restored. The films, which show people moving in and out of Victorian factories, paint an evocative picture of a time gone by. By noting which hand the people in the film waved in, the duo were able to work out the proportions of left-handers alive at the time.
I interviewed McManus last week about his study, London and his writing as my first proper freelance writing assignment. He had lots to say and said it very well. Have a look at the full interview at Nature Networks.
More on asymmetry:
Asymmetrical brains help us (and fish) to multi-task
Reference: McManus & Hartigan. 2007. Declining left-handedness in Victorian England seen in the films of Mitchell and Kenyon. Curr Biol 17: R793-R794.
Filed under: Being human | 6 Comments »
Posted on 27 August, 2007 by Ed Yong
Using virtual reality illusions, two groups of scientists have managed to simulate out-of-body experiences in the lab – by convincing volunteers that they were actually sitting or standing outside of their own bodies, watching themselves from behind. These studies can tell us a lot about our own self-consciousness.
The idea of an out-of-body experiences seems strange and hokey – certainly not one that would grace one of the world’s top scientific journals. So it may seem surprising it cropped up in not one, but two papers in Science this week.
Out-of-body experiences are rare and can be caused by epileptic fits, neurological conditions such as strokes and heavy drug abuse. Clearly, they are triggered when something goes wrong in our brains. And as usual for the brain, something going wrong can tell us a lot about what happens the rest of the time.
Simply put, if we very rarely have an out-of-body experience, why is it that for the most part we have ‘in-body’ experiences? It’s such a fundamental part of our lives that we often take it for granted, but there must be some mental process that ensures that our perceptions of ‘self’ are confined to our own bodies. What is it?
Two groups of scientists have taken steps to answering these questions using illusion and deception. They managed to experimentally induce mild out-of-body experiences in healthy volunteers, by using virtual reality headsets to fool people into projecting themselves into a virtual body.
Filed under: Being human, Mind and Brain, Neuroscience, Psychology, The Brain | 6 Comments »