I don’t research on evolution any more (sadly I had to give it up as I didn’t have the time) but I still think it is pretty cool. One of the big questions in evolution is why we humans evolved such large brains. These sorts of evolutionary questions are hard to answer definitively partly because it has already happened and we can’t reurun this experiment, and partly because our brain is ferociously complex, and understanding complex things is just hard.

But one hypothesis for why we evolved such big brains is the social brain hypothesis, which basically says we evolved it to interact with other humans. Very crudely speaking, you can imagine that genes for a big brain could spread through the population if a big brained caveman used his big brain to convince a smaller brained caveman to got out on a dangerous hunt for a mammoth, and then slept with the poor sap’s wife.

Sorry for that rather misanthropic example, but evolution is a natural law, it just is, it doesn’t have to make us feel good about ourselves. A more cheery example is that a sense of fairness may, at least to some extent, be hard-wired into our brains by evolution. Indeed, not only into our brains but into the brains of other social animals, such as capuchin monkeys.

Below is a short (2 minutes) clip of the well-known Dutch anthropologist Frans de Waal introducing a short film showing a capuchin monkey acting pretty narked by unfairness

http://youtu.be/g8mynrRd7Ak

Thanks to Brian Richards for pointing it out. I feel the pain of the capuchin monkey on the left. I guess you do too, at one time or another we all are left with the boring cucumber while someone else has the tasty grapes, and it burns. It seems likely that at least some extent, the genetically programmed process that builds our brains is hard-wired to make brains that can appreciate fairness and react badly to perceived unfairness.

Our modern societies are much much larger than the social groups we lived in when our large brain was evolving. But if the social brain hypotheses is largely correct then when politicians are campaigning, and us when we are trying to judge which one to vote for, are using our brains for the purpose they evolved for. Ironically, when scientists are using their brains to try and understand evolution, they are not using them for the purpose they evolved for.

And it gets worse for me. The first number systems were developed in the first civilisations basically for tax and accountancy purposes. So when I am doing some calculations to try and understand some part of the natural world, I am using  a brain evolved for politics, and a number system developed for taxation.