I thought for sure this article on the complexity of the human-chimpanzee evolutionary split would generate a lot of news.
To my surprise, according to Google News, it appears to have passed quietly.
So I will summarize: The conventional view is that humans and chimps split off an evolutionary tree about 7 million years ago from a common ancestor, with no inbreeding. Science News picks up the story from there:
Previous work underestimated genetic similarities in people and chimps, the investigators say, and placed the evolutionary parting of these species about 1 million years too early.
Given the new genetic findings ... it's plausible that after a partial split, hominid interbreeding with chimps yielded fertile females and infertile males, Reich and his colleagues propose. Hybrid females would then have resorted to mating with fertile chimp or hominid males.
Because they would have produced fertile sons only when the mothers passed on X chromosomes mostly from one of the original species, this process eventually would have led to a final split.
Several anthropologists dispute this conclusion in the Science News article, which strikes me as a pretty radical shift in the prevailing views. Still, I have to believe we are just seeing the tip of the iceberg in terms of the power of genetics to illuminate the history of life.
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