Update: That charlatan David Klinghoffer seems to be enjoying this. As a rule I don’t follow dishonest propagandists, but it’s interesting how appealing this sort of “two sides” story is to Creationists. End Update
Reading this article this morning, DNA and Fossils Tell Differing Tales of Human Origins, really aggravated me. I believe that it’s totally misrepresenting the tensions in the scientific process here, and misleading the public. The standard conflict/”two views” format is used, and to disastrous effect. Here are some of the sections which I found alarming:
The geneticists reached this conclusion, reported on Thursday in the journal Cell, after decoding the entire genome of three isolated hunter-gatherer peoples in Africa, hoping to cast light on the origins of modern human evolution. But the finding is regarded skeptically by some paleoanthropologists because of the absence in the fossil record of anything that would support the geneticists’ statistical calculation….
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In a report still under review, a third group of geneticists says there are signs of Neanderthals having interbred with Asians and East Africans. But Neanderthals were a cold-adapted species that never reached East Africa.
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Although all known African fossils are of modern humans, a 13,000-year-old skull from the Iwo Eleru site in Nigeria has certain primitive features. “This might have indicated interbreeding with archaics,” said Chris Stringer, a paleoanthropologist at the Natural History Museum in London. “For half of Africa we really have no fossil record to speak of, so I think it’s quite likely there were surviving archaic forms living alongside modern humans.”
Paleoanthropologists like Dr. Klein consider it “irresponsible” of the geneticists to publish genetic findings about human origins without even trying to show how they may fit in with the existing fossil and archaeological evidence. Dr. Akey said he agreed that genetics can provide only part of the story. “But hopefully this is just a period when new discoveries are being made and there hasn’t been enough incubation time to synthesize all the disparities,” he said.
I could have quoted the whole piece and highlighted aspects which I think mislead in terms of public perception. There’s just so much. First, a minor factual issue: I’ve seen presentations on the East Africa Neandertal admixture, and the researchers seem to assume that that is due to “back migration” from Eurasia. In other words, the point about Neandertals being cold-adapted is irrelevant. Second, the big issue seems to be that some paleoanthropologists are unhappy. This is not a debate between all paleoanthropologists and all geneticists. In fact, some genetics are moderately skeptical of admixture because they think it might be due to population structure in the ancient African H. sapiens sapiens. Even within the article you have Chris Stringer, a paleoanthropologist, giving a straightforward reason for why there is a mild discordance here: a lacunae in the fossil coverage across much of Africa due to difficulties of preservation.
The major dynamic to me seems to be that Richard Klein, admittedly a very prominent paleonanthropologist, is also very ticked off. He has some reason to be. Much of the framework within which he has worked is now being shifted (see The Dawn of Human Culture). Klein’s model is that modern humans emerged as a singular speciation event within Africa, and rapidly expanded and replaced other human lineages in totality due to their peculiar genetic innovations (e.g., language). This is hard to align with the current genomic data. But Klein’s views are not the only ones within paleoanthropology. People like John Hawks, Milford Wolpoff, and Erik Trinkaus are no doubt excited by the new statistical inference techniques because they supports their own models, more or less.
What are you seeing here is a battle within paleoanthropology. It is probably correct that statistical geneticists should take more care to integrate fossils into their interpretative frameworks, but there are still plenty of fossil people who feel vindicated by the new genomic findings even granting this objection. Additionally, even those who don’t necessarily taking heart from these findings, such as Chris Stringer, are revising their own viewpoints. You can see the “other perspective” (i.e., not Klein’s) in this paper in Journal of Human Evolution: Did a discrete event 200,000–100,000 years ago produce modern humans?.
I do want to be clear here that I think Richard Klein and his camp are free to feel aggrieved. Science is about dispute and disagreement in many ways. But I think The New York Times does a disservice by confusing what is really a within field controversy into one between two scientific teams.
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