Can someone send me the article below:
The complete mitochondrial DNA genome of an unknown hominin from southern Siberia
doi:10.1038/nature08976
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature08976.html
Here is the abstract:
With the exception of Neanderthals, from which DNA sequences of numerous individuals have now been determined1, the number and genetic relationships of other hominin lineages are largely unknown. Here we report a complete mitochondrial (mt) DNA sequence retrieved from a bone excavated in 2008 in Denisova Cave in the Altai Mountains in southern Siberia. It represents a hitherto unknown type of hominin mtDNA that shares a common ancestor with anatomically modern human and Neanderthal mtDNAs about 1.0 million years ago. This indicates that it derives from a hominin migration out of Africa distinct from that of the ancestors of Neanderthals and of modern humans. The stratigraphy of the cave where the bone was found suggests that the Denisova hominin lived close in time and space with Neanderthals as well as with modern humans
Insteresting stuff, but not the only interesting new article out…
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Afarensis: Anthropology, Evolution, and Science 
Hi afarensis, I sent the article to (I think) the most recent email I have for you. Let me know if you need the Supp Info too.
Imagine that – THREE hominin species living in the same neighbourhood at (roughly) the same time. Quest for Fire, anyone?
Done.
Okay, the species — if species it is —- separated from the line that led to humans and neanderthals one million years ago. How old are the bones. From the abstract it could be the remains of a Homo erectus. If a new species, and recent, it maybe our first specimen of H. Almastai and proof of a contemporary alternate species of human.
Proof of yeti or sasquatch?
Not likely, from descriptions it is fairly evident those two animals, while bipedal apes, are hardly what you’d call human. Since Homo altai (to give him a provisional name) has been identified as human he hardly be a yeti or sasquatch or ancestral to either.
So, how old are the bones?
Found the Wikipedia page on the subject. The remains are about 41,000 years old, and a bracelet of some sort was found associated with them. This last indicating the ability to engage in decorative behavior. The species Denisova Girl belonged to would then be the third species of human known to decorate himself, after modern humans and neanderthals. The page also mentions nuclear DNA studies being done on what material has been found, but says that those results were yet to be released at the time of publication. News stories from Reuters and the New York Times are linked to as well
So at present it would appear that some 41,000 years ago there were 4 species of human running around, sapiens, neanderthaliensis, floresiensis, and altai. Or humans, ogres, hobbits, and elves. 🙂
Now here’s something interesting. Turns out Denisova Cave is a neanderthal site. So far the girl is the only elf found there. She might be the remains of a meal, or at the other extreme an ogre adoptee. Either way she would be proof of interaction between. human species.
BTW, the bracelet mentioned turns out to be a carved piece of stone and might be neanderthal in origin. If it was the girl’s it might be a gift from her adoptive neanderthal parents. Considering how much work stone carving is, if it was a gift from ogre to elf it would indicate a degree of deep affection.
Seems to be some post depositional mixing in the strata the bone came from, Krause et al – in the supplementary material argue for caution in interpreting that level…
So the elf could be younger than 41,000 years, or older. Let’s hope they find additional skeletal material, and material from other individuals of the same species.
I would not be so quick to by into the idea that it is a separate species – testing that particular hypothesis hasn’t been done yet and probaly couldn’t be with the material at hand.
Isn’t that the message of the abstract, of a new species of human based on the mitochondrial DNA?
Yes, but…
One man’s take. Me thinks you and John are being excessively cautious in this matter. Better than being excessively optimistic, but not that much better. Better yet to say, “We don’t know.”
I’ll lean towards optimism, while awaiting nuclear DNA testing. At the moment, based on the MtDNA I think it most likely she is a specimen of a new species, though additional evidence may say differently.
BTW, now that you have the article how is the assimilation of the data going?
I have to wonder about the Neanderthal-Denisova pairwise nucleotide differences. Bear in mind that gene trees are not species trees.
Sounds like your blog post on the subject is going to be interesting. Now, are we talking about Nuclear DNA pairwise differences, or mtDNA pairwise differences?
BTW, while gene trees may not be species trees, after almost a million years of separation I think you can bet on a pretty close match. Hell, in some clades we’d be talking genera or families.
I think because the 95% C.I. of TMRCA slightly overlaps with the time that H. heidelbergensis existed, we cannot reject the hypothesis of the Denisova individual = a descendant of H. heidelbergenesis, but if H. heidelbergenesis were ancestors of Neanderthals, the ancestors of Neanderthals and the Denisova individual were genetically quit different. What do you guys think?
I forgot about H. ergaster and that is another possibility in addition to H. heidelbergensis. If we believe that Asian H. erectus was a different species from African H. ergaster who were direct ancestors of H. heidelbergenesis, H. neanderthalensis, and H. sapiens, the Denisova individual could be a descendant of H. ergaster who took very different evolutionary path from Neanderthals and Anatomically modern human. The 95% C.I. of TMRCA (1.-0.7) also slightly overlap with the time H. ergaster existed in East Africa (1.8-1.3 mya).
It could also be previously unsampled variation in the Neanderthal lineage.
I considered the possibility of an unsampled Neanderthal, too. I feel like I am trying to get too much from TMRCA, but I thought that the TMRCA is too old, considering that Neanderthals analyzed so far is genetically not diverse and effects of drift affecting mtDNA is strong because of small effective population size of mtDNA. If, in fact, the Denisova individual was a Neanderthal, Neanderthal was genetically much more diverse than many genetic researchers thought and phylogenetic tree suggests that Neanderthals were ancestors of modern human. Judging from the genetic evidence we have, this is unlikely scenario. Of course, we should not conclude that the Denisova individual was not Neanderthals, because we do not know enough about this individual or human evolution.
Wel, what we have to go by right now is the mtDNA analysis, and that says the specimen differed substantially from both humans and neanderthals. So being parsimonious I have to learn towards a third species. That’s my stance until additional evidence points in another direction.
The child could be a neanderthal. She could be H. ergaster, though the latter would be an extremely late surviving specimen considering. But the mtDNA tells me we’re telling with a hominin rather distantly related to humans and neanderthals. A comparison with the mtDNA of ergaster, and erectus, could tell us a lot, but until such a comparison is made the available evidence tells me that we are dealing with a new species.
That’s how I operate, when the available evidence says something is thus and so, I take the evidence at its word. When I see footage of a new species of great ape I don’t decide it has to be fraudulent simply because this new species lives in North America. When I read about a new species of human discovered through mtDNA analysis I don’t decide the animal must be some variation on another, known species because she just might be. That is speculation, and speculation can lead one astray.
The discovery of additional remains could point to a close kinship to neanderthals or modern humans. An analysis of the of girl’s nuclear DNA — beyond that needed to sex her that is — may also place her in the two contemporaneous species of human. That said, they may firmly place her in her own species. I may, in short, be wrong. But until the work is done showing that she was a modern human or a neanderthal I will maintain my stance that she is a new species and is to be treated as such.
So, are we to see a blog post out of this?