"We have the same genetic code for all living creatures. We have a large number of genes that are manifestly the same, but with detail differences - they look like different drafts of the same book. In extreme cases, like a human and a beetroot, it's like the difference between Matthew and Luke's Gospel - clearly they tell the same story, but with different words. Whereas with a human and a chimp, it's like two different printings of Matthew, with a few typos in one."