Another Neandertal paper in Proceedings of the Royal Society B. But, because there is a delay between when the press is released to talk about it, and when it goes live, I haven’t gotten a look at the primary material. There’s a lot of juicy stuff in this piece at NBC Science though, Brain comparison suggests that Neanderthals lacked social skills. The two scientists giving quotes, Chris Stringer and Robin Dunbar, know their stuff (one of Dunbar’s graduate students also contributed heavily). In case you don’t know Stringer, he is the paleoanthropologist who was most forceful in pushing for the “Out of Africa” model. Dunbar is the popularizer of Dunbar’s number. I’m assuming Stringer brings the anatomy to the game, while Dunbar frames the bigger theoretical picture. Basically the morphology of the cranium implies that Neandertals may have allocated more of their cognitive capacity to vision and coordination, and less to social activities (because there’s not as much room for the latter). This explains how Neandertals could have a larger cranial capacity than modern humans (they did, though so did Ice Age modern humans) but be somewhat less “intelligent” than us (regular readers know I’m not a big fan of scare quotes for intelligence, but in this case I think it’s warranted).
The main problem I have isn’t the conclusion. It’s plausible enough. But the whole framework of understanding the difference between ourselves and Neandertals has changed in the past 10 years. In short, 10 years ago it might be defensible to assert Neandertals were another species. This is not so today. Rather, most of us are Neandertals (in part). When Richard Klein wrote the Dawn of Human Culture the chasm between Neandertals and humans in a phylogenetic sense was large. This made more plausible sharp and crisp differences in traits between the two distinct and separate populations. Now it is harder to maintain that cordon, because it seems likely there was admixture between modern humans and Neandertals. The difference between Neandertals and moderns has now become one of degree, rather than kind. So, for example, the idea that Neandertals were at the far end of the autism spectrum based on some suggestive genes.
Papers will be published and careers will be made positing traits which led to the downfall of Neandertals. But until the phylogenetic origin of our own lineage, and possibly those of sister lineages, becomes more rock solid I think this is not particularly useful. We can’t bring back Neandertals and run experiments, so any hypothesis and inference generation system must be interpreted in light of background assumptions. Currently we are picking up signs of punctuated admixture events, but what if there was more constant gene flow between different human lineages? The behavioral differences may be subtle indeed if the latter occurred.
Why we are not mostly Neandertal is I think more soluble right now than understanding the evolution of language. But I don’t think there’s any problem right now in confidently admitting that we really don’t know a lot of things.