How many gene mutations does it take to make a human out of something that looked very much like today's chimpanzee? It is a question frequently posed by the popular science media ever since the publication of the full read-out of the chimpanzee genome, less than five years ago.
The real story, however, is much more complicated - but also much more interesting - than the simplistic notion that "human-ness" can be accounted for by a mere 1.6% difference between the genetic code of humans and chimps. It involves the genetic foundations of language and the huge relative size of the human brain, our immune systems, our diet, and aspects of our behaviour. Chimpanzees are proving useful to our quest to find out how we became human, why, and when, but they are NOT watered-down versions of us and we are NOT chimps with a genetic tweak!.

Jeremy Taylor has been a broadcaster of popular science all his working life and has recently turned to science writing with his first book "Not A Chimp: The Hunt To Find The Genes That Make Us Human.