The Christmas edition of the Economist ran a feature on human evolution. I found one of the sections in particular quite interesting: the suggestion that the brain is like a peacock’s tail. That’s to say, it’s a over-the-top demonstration of the owner’s genetic fitness. It’s clear that brains are expensive (2% of the body, using 20% of the energy intake) and there are a bunch of things we do which it could be argued don’t help us survive, but might help us mate: dancing, painting, music, language.
The article caused me to remember the book Galapagos . One idea in that novel is that brains—when they get to a certain size—are more trouble than they’re worth. The evidence offered to support this is the fact we spent so much time trying to silence our brains with alcohol 🙂