???

I didn’t say this at all.

Not talking about something that is true doesn’t make it untrue. The differences exist in the real world.

I’m not going to debate the political implications; I just want the record to be set straight whatever it may be.

Jason Malloy nails it when he says that Hawk himself is seeing the world through PC glasses: we also don’t know just how many genes were transferred and then subsequently lost for lack of fitness advantage. We should all want to know what the function of the genes are that were preserved.

Just to let people know, Hawks has had a second post up, addressing (and arguing against) “alternate interpretations” such as were described here, at Dienekes’, and in Carl Zimmer’s post. If I feel competent to say anything after reading Hawks, I will.

Actually, the fact that Europeans and Neanderthals co-existed for 1000s of years in Europe, and yet Europeans show no more admixture than Asians (even despite the fact that they could’ve used far more alleles than the Asians) would seem to indicate that humans and Neanderthals did behave like separate species. No natural hybridization in overlapping range? Not same species. (That’s the biological species concept.) This is unsurprising given our deep phylogenic divergence, and the persistent, complex behavioral differences between Sapiens and Neanderthalensis.

Introgression doesn’t demand a reliable behavior pattern, only a handful of one-off encounters. So introgression can’t be used to argue for unity of species.

In reality, they are never quite 100% fated to stay apart – it’s always probabilistic. It’s somewhat contingent upon ecological conditions, which could change arbitrarily at any moment. But if they’re highly likely to never fully merge, I’d call them good species. If wolves and coyotes are amalgamating in a way that looks like it will probably go all the way, I call them one species.

Of course, using my species concept, there can be a gray area where the probability of mergation/non-mergation is not 5/95, nor 95/5, but something closer to 50/50. This gray area is ugly, and the classical biological species concept doesn’t have a gray area. But ‘my’ concept (which I’d guess has been discussed a lot since before I was born) makes more sense on a large-scale diachronic view.

Heck, humans and chimps may even be interfertile, it has been speculated:
http://en.wikipedia.org/wiki/Humanzee

personally, i don’t think it is important whether x and y belong to different species because i don’t think of species as metaphysical entities, like creationists believe with “kinds.” it’s just shorthand to describe other things, like genetic distance or occupation of different niches in the same ecology, etc.

We don’t consider Wolves and Dogs the same species as Coyote. Dogs and Wolves are generally considered subspecies, similar to Human and Neanderthals. There are other examples as well.

naked animals aren’t sexual (i think that’s the implicit model being exposed here, and it doesn’t have a left-right difference).