tag:blogger.com,1999:blog-7315236707728759521.post6609272158299333551..comments2024-03-27T22:28:06.861-06:00Comments on Dispatches From Turtle Island: Ancient mtDNA from Homo heidelbergensis rocks paradigmsAndrew Oh-Willekehttp://www.blogger.com/profile/02537151821869153861noreply@blogger.comBlogger8125tag:blogger.com,1999:blog-7315236707728759521.post-79298894524318604322013-12-15T20:27:57.848-07:002013-12-15T20:27:57.848-07:00"The question needs to be asked why is our sp..."The question needs to be asked why is our species or breed the last left? Why are we so superior to the rest?" <br /><br />Given the timing of the point at which modern humans became dominant, dog domestication is a pretty likely candidate.andrewhttps://www.blogger.com/profile/08172964121659914379noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-18108092804181213842013-12-07T19:52:00.317-07:002013-12-07T19:52:00.317-07:00"The question needs to be asked why is our sp..."The question needs to be asked why is our species or breed the last left? Why are we so superior to the rest?" <br /><br />It is 'superior' because it has accumulated the 'best' genes from all the previous species. It is becoming more and more obvious that various human species have contributed to the modern human gene pool, leaving open the possibility that the various 'species' were often completely inter-fertile. terrythttps://www.blogger.com/profile/17327062321100035888noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-76167213799297478702013-12-06T15:10:01.844-07:002013-12-06T15:10:01.844-07:00I am skeptical how distinct these species were and...I am skeptical how distinct these species were and how we are able to classify them so well. All the different skeletal remains called Neanderthals may be many very unrelated breeds. Since Densovian autosomal DNA was more related to the Neanderthal sample than Neanderthals are to modern humans but the Neanderthal mtDNA lineage is closer to modern humans. That would mean that there was mixing between different human breeds. That also means it is a possibility Heidelbergensis was ancestral to Neanderthals.<br /><br />Human species must have been out of Africa for a very long time. SinceNeanderthals,Heidelbergensis, and Densovians all originated in Eurasia. It is possible modern humans descend from a back migration to Africa or didn't originate in Africa at all.<br /><br />The question needs to be asked why is our species or breed the last left? Why are we so superior to the rest? Krefterhttps://www.blogger.com/profile/01055804913528477710noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-62726530424281834982013-12-06T15:04:27.293-07:002013-12-06T15:04:27.293-07:00A Hobbit observation that seems a good fit with th...A Hobbit observation that seems a good fit with the DNA link is <a href="http://en.wikipedia.org/wiki/Homo_floresiensis" rel="nofollow">this one:</a><br /><br />"Tocheri et al. (2007) (including Morwood, Larson, and Jungers), compared three carpal bones believed to belong to LB1 with carpal bones of modern humans, some earlier hominids and African apes. They concluded that the carpals from the Liang Bua cave resembled ape carpal bones and were significantly different from the bones of H. sapiens, Homo neanderthalensis or even Homo antecessor, and that they were comparable to carpal bones of Australopithecus. The carpal bones of H. floresiensis were found to lack features that evolved with ancestors of modern humans at least about 800,000 years ago. These features are already formed during embryogenesis and therefore Tocheri et al. argue that it is improbable that the shape of H. floresiensis wrist bones could be a result of a developmental disease. This evidence also suggests that H. Florensiensis is not a modern human with an undiagnosed pathology or growth defect, but that it represents a species descended from a hominin ancestor that branched off before the origin of the clade that includes modern humans, Neandertals, and their last common ancestor.[9]"<br /><br />The archaic hominin Flores population seems to date from about 850,000 years ago +/- about 10,000 years, which is pretty close in time to <a href="http://en.wikipedia.org/wiki/Homo_heidelbergensis" rel="nofollow">H. Heid.'s appearance.</a><br /><br />The possibility that they thrived in Flores since they didn't have to compete with H. Erectus there because they could reach it and Erectus could not makes sense to me.andrewhttps://www.blogger.com/profile/08172964121659914379noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-60600188477236939392013-12-06T14:04:24.992-07:002013-12-06T14:04:24.992-07:00"H. floresensis is merely Hss locally adapted..."H. floresensis is merely Hss locally adapted to unusual conditions, derived from pygmy-San ancestors" <br /><br />I agree with the 'locally adapted to unusual conditions' bit but am extremely doubtful of the 'derived from pygmy-San ancestors'. <br /><br />"A post-Wallace line introgression is still very plausible". <br /><br />'A post-Wallace line introgression' is basically impossible, unless the Flores population maintained a 'Denisova' element for something like half a million years. There was no-one else beyong Wallace's Line until modern hujmans crossed it. And preumably they already carried the Denisova element. It has probaly been diminished through Eurasia by the later expansion of populations lacking the element. <br /><br />"there is evidence of hybrid infertility in the loci where introgressed from Neanderthal alleles in modern human are located in the genome". <br /><br />Yes, there is evidence, but I'm not sure how convincing that evidence is. We have the example of Europe which seems to have undergone repeated incursions of haplogroups and genes from elsewhere which have diminished the proportion of older genes. Much of this during just the period of the Neolithic. Over amuch longer period I can easily see how ancient DNA would become greatly reduced as a proportion of current DNA. terrythttps://www.blogger.com/profile/17327062321100035888noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-70117650624620665052013-12-06T13:09:47.920-07:002013-12-06T13:09:47.920-07:00H. floresensis is merely Hss locally adapted to un...H. floresensis is merely Hss locally adapted to unusual conditions, derived from pygmy-San ancestors...Ebu gog = (Bembu congo) IMODDedenhttps://www.blogger.com/profile/10033851770461086341noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-56275116518711455012013-12-05T21:24:01.011-07:002013-12-05T21:24:01.011-07:00The Indonesian admixture assumption is based on th...The Indonesian admixture assumption is based on the location of the introgressed populations and doubt about the subsequent total replacement of that UP population. So, the origins of the Denisova and their route to Indonesia are irrelevant. A post-Wallace line introgression is still very plausible.<br /><br />Able to interbreed doesn't mean that this produced fertile children with the same ease. Indeed, there is evidence of hybrid infertility in the loci where introgressed from Neanderthal alleles in modern human are located in the genome.andrewhttps://www.blogger.com/profile/08172964121659914379noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-91991661967316032992013-12-05T20:15:30.414-07:002013-12-05T20:15:30.414-07:00"Thus, we do now that this 'sub-genus'..."Thus, we do now that this 'sub-genus' identification for the Denisovan implies that the source of Denisovan mtDNA in modern humans must have been intrusive to Indonesia where it probably introgressed into modern human DNA" <br /><br />Intrusive to Indonesia, yes. Unlikely to have introgressed into the modern human population in Indonesia though. As your quote from John Hawks: <br /><br />"Let's explore an alternative: that the Denisovans we know are in part descendants of an earlier stratum of the western Eurasian population. ... But they could share a heritage within the Middle Pleistocene of western Eurasia, deriving their mtDNA from this earlier population" <br /><br />That places Denisove securely in wetern Eurasia, not in the east. <br /><br />"More generally, this evidence seems to support the notion that the hominin evolutionary tree was much bushier than previously suspected with many more unattested species that were not closely genetically related co-existing than we had previously believed". <br /><br />But all able to interbreed successfully. terrythttps://www.blogger.com/profile/17327062321100035888noreply@blogger.com