tag:blogger.com,1999:blog-7785493.post1509578752223994966..comments2024-01-04T04:11:55.717+02:00Comments on Dienekes’ Anthropology Blog: Analysis of five Neandertal Genomes (Briggs et al. 2009)Dienekeshttp://www.blogger.com/profile/02082684850093948970noreply@blogger.comBlogger5125tag:blogger.com,1999:blog-7785493.post-5864325810063512992009-07-20T02:21:31.145+03:002009-07-20T02:21:31.145+03:00They managed to clone the mtDNA like a thousand ti...They managed to clone the mtDNA like a thousand times for little cost, what allows as many replications as possible and rechecking the data as many times a need be without further extractions. <br /><br />I do not understand the technological details though.Majuhttps://www.blogger.com/profile/12369840391933337204noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-36710492389137692052009-07-20T01:47:18.249+03:002009-07-20T01:47:18.249+03:00Also equally interesting is their apparent technol...Also equally interesting is their apparent technological breakthrough that allowed them to obtain DNA from much more degraded/contaminated Naenderthal remains than the Croatian sample sequenced earlier this year.<br /><br />But I tried to understand the method in their supplementary file and couldn't. I saw something about neanderthal DNA having some distinctive thing about it that allowed their scanning machine to eliminate human contaminant sequences, reducing costs 100 fold or more. I dunno, it looks to be something that's going to produce big results in the future of ancient DNA testing. Can someone explain it? Also if it applies to just mtdna, or will it be useful for autosomal DNA, also?argiedudehttps://www.blogger.com/profile/11512295756932222613noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-187470431005931862009-07-19T01:43:02.344+03:002009-07-19T01:43:02.344+03:00"This is a sexy hypothesis, but one not prove..."This is a sexy hypothesis, but one not proven at all". <br /><br />I agree. Reduced mtDNA diversity in cold-adapted populations is as likely to be a product of sequential periods of selection amoung migrants into such regions as being due to bioenergetic adaptation. Such selection would also account for the much reduced Neanderthal mtDNA diversity, especially as they seem to have been isolated from any genetic input for much more than 100,000 years if not half a million.terrythttps://www.blogger.com/profile/17327062321100035888noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-11400050299891886922009-07-18T00:27:02.391+03:002009-07-18T00:27:02.391+03:00Even among current cold-adapted populations, mtDNA...<i>Even among current cold-adapted populations, mtDNA diversity is reduced, and this is due to bioenergetic adaptation for a cold climate.</i><br /><br />Reduced mtDNA diversity in cold-adapted populations has not been demonstrated to be DUE to bioenergetic adaptation. This is a sexy hypothesis, but one not proven at all, and an active battlefield in the ongoing neutral / adaptive debates.The Other Jimhttps://www.blogger.com/profile/17570666738076378921noreply@blogger.comtag:blogger.com,1999:blog-7785493.post-69675391773417849972009-07-17T02:40:40.179+03:002009-07-17T02:40:40.179+03:00Fascinating info, thanks.
I really find it hard ...Fascinating info, thanks. <br /><br /><i>I really find it hard to believe that Neandertals died out beause of competition with Homo sapiens. After all, a population of a few thousand could quite easily have been accommodated in Paleolithic Europe; population density was so low, that there were plenty of resources for modern humans and Neandertals alike</i>. <br /><br />I'd say that if "population density was so low" it was precisely because those were the figures the resources allowed for that kind of economy. <br /><br />Along time there may be moments when population is suboptimal or exceeds the optimal figure. But, in the latter case, Malthusian brakes act as regulators - the population can never really grow above the viable figures without immediately decreasing due to scarcity and its derived high mortality. And when the population is suboptimal, natural demographic growth will soon make it reach the optimal figures. <br /><br />And I don't think this would be different for Neanderthals. At most their economic system could have been somewhat different from ours (smaller foraging range for example). So I don't think the objection is valid (though maybe the speculated figures are not correct - can't say). <br /><br />The Live Science article also says that <i>The Neanderthals had about three times less genetic diversity than the modern humans</i>. <br /><br />I find this surprisingly high in fact. After all, modern humans are almost 7 billion people and even 50 kya H. sapiens already occupied more than three times the range of Neanderthals, what probably means that they were already more than three times their numbers.Majuhttps://www.blogger.com/profile/12369840391933337204noreply@blogger.com