Science has a reason - chimps are more evolved.
Since the human-chimp split about 6 million years ago, chimpanzee genes can be said to have evolved more than human genes, a new study suggests.Link. While scientists point to population size playing an important role in natural selection, and therefore our evolutionary lineage, I feel they are overlooking the obvious - the chimp's ability to overcome sterilization, which has been naturally selected for in the recent generations.
The results, detailed online this week in the Proceedings of the National Academy of Sciences, contradict the conventional wisdom that humans are the result of a high degree of genetic selection, evidenced by our relatively large brains, cognitive abilities and bipedalism.
Jianzhi Zhang and Margaret Bakewell of the University of Michigan and a colleague found that substantially more genes in chimps evolved in ways that were beneficial than was the case with human genes.