What can gene expression in the brain tell us about human evolution?
I think we only compared the liver, blood, and brain, and we chose liver and blood because they were organs and systems where there didn’t seem to be many differences. Now there are many other situations where there are rather dramatic differences. For example, the skin is the obvious one. The skin is obviously very different from that of the chimp, and hair and other things like that. There’s some evidence that the reproductive system is somewhat different. For example, the breasts are very different. Other tissues where there are differences might be in the muscle. Chimpanzees are much stronger than humans. They seem to be much stronger for reasons that are not clear. There are structures like the sinuses, and things like that, which are different. So there are many other organs where there are differences between humans and chimpanzees, and of course brain is the one that we all tend to be primarily interested in. In fact I have the view that it’s not going to be easy to figure out.
