Joined: Jan. 2006
In the "AFDave doesn't know squat about the evolution of apes" topic (that I don't want to continue) we were dicussing the divergence time between our lineage and chimps and also the fact that genomic data contradict paleontological data.
I think this paper in the latest issue of Nature is worth reading, for those who have a subscription.
|Genetic evidence for complex speciation of humans and chimpanzees|
Nick Patterson1, Daniel J. Richter1, Sante Gnerre1, Eric S. Lander1,2 and David Reich1,3
The genetic divergence time between two species varies substantially across the genome, conveying important information about the timing and process of speciation. Here we develop a framework for studying this variation and apply it to about 20 million base pairs of aligned sequence from humans, chimpanzees, gorillas and more distantly related primates. Human–chimpanzee genetic divergence varies from less than 84% to more than 147% of the average, a range of more than 4 million years. Our analysis also shows that human–chimpanzee speciation occurred less than 6.3 million years ago and probably more recently, conflicting with some interpretations of ancient fossils. Most strikingly, chromosome X shows an extremely young genetic divergence time, close to the genome minimum along nearly its entire length. These unexpected features would be explained if the human and chimpanzee lineages initially diverged, then later exchanged genes before separating permanently.