Structural comparison of chimpanzee (left) and human (right) brains. The human brain shows a much more marked asymmetric shape than the chimpanzee brain.
The two halves of the human brain are not symmetrical. This lopsidedness, which arises during brain development, may be a stamp of the adaptability of the human brain, a new study suggests.
Researchers compared geometric differences between brain scans of humans and chimpanzees. They observed structural asymmetries in both human and chimpanzee brains, but human brains were especially asymmetric. The findings, published online today (April 23) in the journal Proceedings of the Royal Society B, suggest human and chimp brains evolved a high degree of flexibility during development.
For the rest of the story: http://www.livescience.com/28986-humans-evolved-asymmetric-brains.html