tag:blogger.com,1999:blog-7315236707728759521.post2396608217076917546..comments2024-03-28T21:52:52.100-06:00Comments on Dispatches From Turtle Island: Ancient Neanderthal Y-DNAAndrew Oh-Willekehttp://www.blogger.com/profile/02537151821869153861noreply@blogger.comBlogger3125tag:blogger.com,1999:blog-7315236707728759521.post-20631666133353413022016-04-13T17:48:13.263-06:002016-04-13T17:48:13.263-06:00I think it is becoming increasingly difficult to a...I think it is becoming increasingly difficult to accept anything other than that the ancestors of modern humans must have moved into Africa some time after they split from Neanderthals. That is around half a million years ago. Neanderthals must have formed from Denisovans (most likely what used to be called H. heidelbergensis) somewhere in Eurasia. The separation of Neanderthals and moderns may simply have been caused by increasing aridity through the Sahara/Arabian Peninsula. terrythttps://www.blogger.com/profile/17327062321100035888noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-55820536956386551432016-04-11T11:00:43.337-06:002016-04-11T11:00:43.337-06:00"This also corroborates that Y-DNA A00 is unl..."This also corroborates that Y-DNA A00 is unlikely to be an introgression from an archaic hominin species"<br /><br />I think that would depend on your definition of archaic. If it's quite literally intermediate between modern humans and the modern human / Neanderthal common ancestor, I think that's a pretty interesting edge case.Ryanhttps://www.blogger.com/profile/07906194112935320590noreply@blogger.comtag:blogger.com,1999:blog-7315236707728759521.post-38070167634203663132016-04-09T17:51:02.942-06:002016-04-09T17:51:02.942-06:00"Indeed, reduced fertility or viability of hy..."Indeed, reduced fertility or viability of hybrid offspring with Neandertal Y chromosomes is fully consistent with Haldane’s rule, which states that 'when in the [first generation] offspring of two different animal races one sex is absent, rare, or sterile, that sex is the [heterogametic] sex'." <br /><br />To me that is a sufficient explanation. In most pairs of mammalian species male fertility is the first to drop off as the species become more separated in time. Obviously it is not a purely linear relationship as some species separated by as much as a million years do not exhibit male sterility, but in others it can be as little as half a million years, which is the time between modern and Neanderthal. I have read many ridiculous ideas of why the Neanderthal Y-DNA has died out such as the Anthropology blog, where they ignore the obvious: <br /><br />https://anthropology.net/2016/04/09/modern-males-lack-neanderthal-y-chromosome-genes/<br /><br />If two species form hybrids where the F1 males are unable to reproduce then obviously just one male line will come to dominate even if hybrid females are able to successfully reproduce. But if hybrid individuals are accepted into the mother's species and just one of those species comes to dominate then the mt-DNA from the species that becomes extinct will also become extinct. terrythttps://www.blogger.com/profile/17327062321100035888noreply@blogger.com