Maybe it was the seriousness of the patient's condition. Or maybe chimp and human kidneys aren't so much alike after all. One thing is clear, however. True, we both have large brains, can walk on two legs, use tools, and spend years nurturing helpless infants. Chimps have shorter thumbs and much more hair.
Female chimps have breasts only when they are nursing and the males have bones in their penises.
And of course, humans are a lot smarter. Clearly there is something about that 1.5 per cent of the genome that counts for a lot. Something that gives Homo sapiens the ability to read magazines and sing along with the car radio, while our chimp cousins are better adapted for life in the jungle, climbing trees and fishing for termites with twigs. Now a group of geneticists, molecular anthropologists, evolutionary biologists and primatologists are searching for the genetic changes that make the difference. All we can do is look.