Per http://en.wikipedia.org/wiki/W%C3%BCrm_glaciation and the figure "Vegetation types at the last glacial maximum", at roughly the time of the suggested in migration to Tibet, the vegetation was "polar and alpine desert" (if I can correlate the colors correctly). What would push a population (thought to be small?) to such a climate when other areas of southeast Asia have vegetation types that seem to be much more suitable for human occupation?
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I have no financial, professional, organizational, institutional, academic, familial or other competing interests.
Authors Reply
Roscoe Stanyon, University of Florence and Bologna
16 February 2009
Due to space limitations we did not discuss completely the evidence for the hypothesis that Tibetan settlement could well be earlier than that of Japan. We noted that the genetic diversity is much higher, usually considered indicative of earlier settlement, and that the coalescence time of the Tibetan Y chromosome sublineage is older than that of Japan (52,000 vs 37,000). We can add here that Shi et al also noted that the both the Tibetan and Japanese sub-haplogroups have a short-distanced, star-like network structure, typical of founding lineages. Further, the earliest material evidence for modern humans in Japan is at 30,000 year ago while recent archeological data shows modern human presence in Northern Tibet is as least as old if not older (30 to 40,000 year ago). All these data are consistent with an ancient settlement date for Tibet. We cannot judge the detail and the accuracy of the Wikipedia entry, but it is clear that at least some parts of Tibet were apparently hospitable for humans earlier than previously thought. Finally, current research deals mostly with questions of the when and where of modern human migration. The questions of why raised in this comment are not only more challenging, but also more rewarding and certainly will eventually be the subject of future research.
Settlement of Tibet
16 February 2009
Per http://en.wikipedia.org/wiki/W%C3%BCrm_glaciation and the figure "Vegetation types at the last glacial maximum", at roughly the time of the suggested in migration to Tibet, the vegetation was "polar and alpine desert" (if I can correlate the colors correctly). What would push a population (thought to be small?) to such a climate when other areas of southeast Asia have vegetation types that seem to be much more suitable for human occupation?
Competing interests
I have no financial, professional, organizational, institutional, academic, familial or other competing interests.
Authors Reply
16 February 2009
Due to space limitations we did not discuss completely the evidence for the hypothesis that Tibetan settlement could well be earlier than that of Japan. We noted that the genetic diversity is much higher, usually considered indicative of earlier settlement, and that the coalescence time of the Tibetan Y chromosome sublineage is older than that of Japan (52,000 vs 37,000). We can add here that Shi et al also noted that the both the Tibetan and Japanese sub-haplogroups have a short-distanced, star-like network structure, typical of founding lineages. Further, the earliest material evidence for modern humans in Japan is at 30,000 year ago while recent archeological data shows modern human presence in Northern Tibet is as least as old if not older (30 to 40,000 year ago). All these data are consistent with an ancient settlement date for Tibet. We cannot judge the detail and the accuracy of the Wikipedia entry, but it is clear that at least some parts of Tibet were apparently hospitable for humans earlier than previously thought. Finally, current research deals mostly with questions of the when and where of modern human migration. The questions of why raised in this comment are not only more challenging, but also more rewarding and certainly will eventually be the subject of future research.
R. Stanyon, M. Sazzini & D. Luiselli
Competing interests
None