This paper has been for more than a week in my "to do" folder and I really think it deserves a separate mention even if it also leaves me a bit cold:
Xiaouyun Cai et al., Human Migration through Bottlenecks from Southeast Asia into East Asia during Last Glacial Maximum Revealed by Y Chromosomes. PLoS ONE 2011. Open access.
The authors think that they can track overall Y-DNA flow between Austroasiatic and Hmong-Mien speakers in SE Asia and they therefore believe that, genetically speaking, Austroasiatic peoples are "ancestral" to Hmong-Mien.
It does not contradict anything I generally espouse for the demographical history of the region, rather the opposite but still it leaves me quite cold. Why? Because the analysis is based on STR rather than SNP-defined phylogeny, what has led to errors in the past, because the authors insist in associating genetics with language and want to somehow argue that Hmong-Mien and Austroasiatic are related just because the speakers are related. That may well be like comparing Jamaicans and Angolans and deciding that way that English and Portuguese are related... and be right by mere chance. Or be wrong or...
Still the supplementary material offers a nice resource for those interested in the detail of East Asian Y-DNA genetics.
There is also some more detailed information on Y-DNA O, always interesting. For example:
|Left to right: O2a1 (M95), O3a2b (M7) and O3a2c1a (M117)|
This is the kind of stuff where you really get the impression of how haplogroups are distributed and why it is likely that they coalesced in the South. But we'd need a more complete work of this kind, addressing all major haplogroups.
So, well, there it is and I'm sure that many readers would be interested in knowing about it. But nothing that shakes the world in any case.
"there it is and I'm sure that many readers would be interested in knowing about it".ReplyDelete
"This is the kind of stuff where you really get the impression of how haplogroups are distributed and why it is likely that they coalesced in the South".
M95 is O2a1, a derived haplogroup long associated with Austro-Asiatic, Kradai and Malay, along with South Asia, so no surprises with the map. But where is O2b for us to be able to draw any valid conclusions regarding deeper origin? M7 is O3a2b, a derived haplogroup long associated with Daxi, Hmong-Mien and Mon-Kmer, and so no surprises with the map. But where are O3a2a and O3a2c for us to be able to draw any valid conclusions regarding deeper origin? M117 is at least a subclade of the latter haplogroup: O3a2c1a. A derived haplogroup long associated with Sino-Tibetan, Japan and East and SE Asia. Again no surprises with the map. How does this information indicate anything other than that these three particular derived haplogroups 'likely that they coalesced in the South'?
By the way. I notice that the auhtors use the 'old' nomenclature, O3a3b-M7 and O3a3c1-M117. ISOGG now calls the haplogroups as above.ReplyDelete
Precisely that's why the paper leaves me a bit cold: it could be wider and more detailed.ReplyDelete
"Precisely that's why the paper leaves me a bit cold: it could be wider and more detailed".ReplyDelete
Yes. It's time someone did some solid work on Y-hap O instead of setting out to 'prove' some political point. I cannot believe that East Austronesian O3a is basal in any way, for example. It has to be 'derived'. I'm sure it is monophyletic, similar to your idea concerning Socotran Y-hap J*.