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Many of you have probably heard that some fossils found in China in 1979 but not analyzed until recently are claimed to represent a new species of hominin, dating to only 12,000 years ago.
Pop story here: http://www.newscientist.com/article/...n-species.html
Original paper (free) here: http://www.plosone.org/article/info%...l.pone.0031918
I know a few of you are interested in paleoanthropological stuff, and one of you wondered if I would give an opinion on this (out yourself if you want).
I recently gave a lecture about Homo floresiensis, a species that probably went extinct at about the same time, and which is, in my opinion, very clearly a species of hominin quite distinct from modern humans. so I'm not only open to late-surviving non-sapiens hominins, but excited by the prospect.
Keep in mind that very recent human fossils aren't my specialty, nor is craniodental material, which isn't all they have but is all they analyze in the paper. Anyway, here's my very brief take:
They mostly use a very generic (principle components) shape analysis of the cranium to build their argument that these folks weren't human. The problem as I see it is that in most of the analyses, the new stuff falls within the modern human range. The one where it doesn't relies heavily on the new specimen's wide cheekbones (cheekbone, actually, since the other side is reconstructed). Wide cheekbones (or flaring zygomatics, if you like) are a primitive feature common among australopiths, so I understand the temptation to see retention of this primitive trait as significant, but if you look closely at the pictures in the paper, you can see that there are at least three fractures in the zygomatic arch that may have been filled in with sediment and in any case seem to be a reasonable explanation for the mediolateral broadening of the malar region.
The mandible does have a fairly weak chin, which the authors find significant, but it seems to be within the human range.
So for now, I don't buy this as a new species, although I reserve the right to change my tune after I see some better analysis. I expect that this will be a hot topic at the annual meetings next month, so I'll let you know if I hear anything.
Pop story here: http://www.newscientist.com/article/...n-species.html
Original paper (free) here: http://www.plosone.org/article/info%...l.pone.0031918
I know a few of you are interested in paleoanthropological stuff, and one of you wondered if I would give an opinion on this (out yourself if you want).
I recently gave a lecture about Homo floresiensis, a species that probably went extinct at about the same time, and which is, in my opinion, very clearly a species of hominin quite distinct from modern humans. so I'm not only open to late-surviving non-sapiens hominins, but excited by the prospect.
Keep in mind that very recent human fossils aren't my specialty, nor is craniodental material, which isn't all they have but is all they analyze in the paper. Anyway, here's my very brief take:
They mostly use a very generic (principle components) shape analysis of the cranium to build their argument that these folks weren't human. The problem as I see it is that in most of the analyses, the new stuff falls within the modern human range. The one where it doesn't relies heavily on the new specimen's wide cheekbones (cheekbone, actually, since the other side is reconstructed). Wide cheekbones (or flaring zygomatics, if you like) are a primitive feature common among australopiths, so I understand the temptation to see retention of this primitive trait as significant, but if you look closely at the pictures in the paper, you can see that there are at least three fractures in the zygomatic arch that may have been filled in with sediment and in any case seem to be a reasonable explanation for the mediolateral broadening of the malar region.
The mandible does have a fairly weak chin, which the authors find significant, but it seems to be within the human range.
So for now, I don't buy this as a new species, although I reserve the right to change my tune after I see some better analysis. I expect that this will be a hot topic at the annual meetings next month, so I'll let you know if I hear anything.
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