Genetic change has been coming 100 times faster in the past 5000 years than at any point in previous history say Robert K. Moyzis of the University of California, Irvine, and Henry C. Harpending of the University of Utah. I imagine they then immediately shouted, NBA Jam-style, "He's heating up!" while fantasizing about the inevitability of women who sprout wings and men who shoot lasers out of their nostrils.
While the more prevalent notion has been that evolution has slowed or halted, favoring cultural rather than biological change, 7% of all human genes showed evidence of recent natural selection.
"The technology can't detect anything beyond about 2,000 years ago, but we see no sign of [human evolution] slowing down. So I would suspect it is continuing," Harpending told BBC News.
The two looked at single nucleotide polymorphisms, single-point mutations in the genetic sequence, to track changes. Their argument is that if the same chromosome from a large group of people shows the same sequence of single-point changes, it's because the useful sequence hasn't been broken up recently.
Their explanation for the boom comes in two forms. First, a population boom came as early modern humans left Africa, giving natural selection more mutations to work on. Second, as we left Africa, we were exposed to new climates and diseases, forcing adaptation. [Also, James Watson has been tinkering in the lab to make himself closer to his ideal than he may well be. Hint: he's growing laser eyes.]
The BBC is mostly positive on the story, though it cites objections from other researchers who say that once population size hits a certain, relatively small point, it stops being a factor in natural selection.
"The general picture that evolution has speeded up in the last 10,000 years as we change from, to put it bluntly, being animals to being humans is clearly true," said geneticist Professor Steve Jones of University College London. "To suggest it is happening at this instant, I would suggest, is probably wrong."
More generally, creationists have merely edited their documentaries with a "No, duh. The earth's only been around for 10,000 years."
The New York Times offers more skepticism from researchers saying that the two authors hadn't been cautious enough with their interpretations as the test begins to fail with more recent and distant changes.
Caution, smaution. We already know our origins are inauspicious [Poop!]. When are my superpowers coming?
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