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To: 240B; 75thOVI; Adder; albertp; asgardshill; At the Window; bitt; blu; BradyLS; cajungirl; ...
IOW, the assumed timeclock in mtDNA mutation rates turned out to be wrong, or to put it another way, mtDNA stability is much greater than previously assumed. Thanks GonzoII.
More approaches have been brought to bear on the emergence and outgrowth of Homo sapiens sapiens (i.e., modern humans) than any other species including full genome sequence analysis of thousands of individuals and tens of thousands of mitochondria, paleontology, anthropology, history and linguistics [61, 142-144]. The congruence of these fields supports the view that modern human mitochondria and Y chromosome originated from conditions that imposed a single sequence on these genetic elements between 100,000 and 200,000 years ago [145-147]. Contemporary sequence data cannot tell whether mitochondrial and Y chromosomes clonality occurred at the same time, i.e., consistent with the extreme bottleneck of a founding pair, or via sorting within a founding population of thousands that was stable for tens of thousands of years [116]. As Kuhn points out unresolvable arguments tend toward rhetoric.Summary and conclusionScience greedily seizes simplicity among complexities. Speciation occurs via alternative pathways distinct in terms of the number of genes involved and the abruptness of transitions [148]. Nuclear variance in modern humans varies by loci in part due to unequal selection [149] and the linkage of neutral sites to those that undergo differential selection. Complexity is the norm when dealing with variance of the nuclear ensemble [150-154]. It is remarkable that despite the diversity of speciation mechanisms and pathways the mitochondrial sequence variance in almost all extant animal species should be constrained within narrow parameters. Mostly synonymous and apparently neutral variation in mitochondria within species shows a similar quantitative pattern across the entire animal kingdom. The pattern is that that most -- over 90% in the best characterized groups -- of the approximately five million barcode sequences cluster into groups with between 0.0% and 0.5% variance as measured by APD, with an average APD of 0.2%. Modern humans are a low-average animal species in terms of the APD. The molecular clock as a heuristic marks 1% sequence divergence per million years which is consistent with evidence for a clonal stage of human mitochondria between 100,000- 200,000 years ago and the 0.1% APD found in the modern human population [34, 155, 156]. A conjunction of factors could bring about the same result. However, one should not as a first impulse seek a complex and multifaceted explanation for one of the clearest, most data rich and general facts in all of evolution. The simple hypothesis is that the same explanation offered for the sequence variation found among modern humans applies equally to the modern populations of essentially all other animal species. Namely that the extant population, no matter what its current size or similarity to fossils of any age, has expanded from mitochondrial uniformity within the past 200,000 years.Mark Stoeckle and David S Thaler, Why should mitochondria define species?

81 posted on 06/10/2018 1:01:46 PM PDT by SunkenCiv (www.tapatalk.com/groups/godsgravesglyphs/, forum.darwincentral.org, www.gopbriefingroom.com)
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To: SunkenCiv

Just as the Bible states. Uh-oh.


82 posted on 06/10/2018 1:06:29 PM PDT by 2ndDivisionVet (You cannot invade the mainland US. There'd be a rifle behind every blade of grass.)
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To: Armscor38; a little elbow grease; alexander_busek; BitWielder1; BroJoeK; central_va; dangerdoc; ...
Of course, the real headline should be, the Earth isn't 6000 years old. :^) To say that the paper currently under discussion (using that term loosely) is an outlier is something of an understatement. At best it could lead to an examination of the basis for the molecular clocks used to estimate dates for mitochondrial DNA mutation branching.

165 posted on 06/13/2018 7:35:29 AM PDT by SunkenCiv (www.tapatalk.com/groups/godsgravesglyphs/, forum.darwincentral.org, www.gopbriefingroom.com)
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233 posted on 11/29/2018 3:17:56 AM PST by SunkenCiv (and btw -- https://www.gofundme.com/for-rotator-cuff-repair-surgery)
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