Endogenous Retro Virus
Viruses that have become part of the genome. See Prediction 4.5 (about 2/3 the way down) for details.
The distribution of ERVs among the primates is illustrated there.
It's not proof of common descent, in the sense of proving the Pythagorean Theorem. However, when dealing with natural phenomena, we *never* have proof in that sense. All we have is proof in the legal sense of "beyond a reasonable doubt".
When you consider that in addition to the illustrated primate phylogenetic tree, the same kind of results have been found everywhere that genomes have been tested, doubt of common ancestry becomes highly unreasonable.
In all of this, the only thing I object to is the interjection of politics, liberal politics, to be precise about it, into the study of evolution, and there's plenty of it.
I don't believe we are any more closely related to Chimpanzees than any other ape for the reasons I illustrated in my analogies regarding cousins, apples, and kumquats.
Science and religion for the most part get along, but clash when it comes to evolution. I side with science, but how important is it?
Although I find evolution fascinating, I have to ask why it's so all fired important to teach it in public schools when there's a sizable portion of the population that rejects it out of hand. Furthermore, people who don't buy into it function just fine. So what's the point? Aren't there plenty of other things available to include in the curriculum besides this topic. The liberals insist on jamming it down everyone’s collective throats as a wedge issue power play. There isn't any other reason to do so.