Controversies in Science/Was there a mitochondrial Eve?/A critique of Absence of Regional Affinities of Neandertal DNA With Living Humans Does Not Reject Multiregional Evolution

From Wikiversity
Jump to navigation Jump to search

(Review Paper) Cited in Controversies in Science/Was there a mitochondrial Eve?/A critique of Absence of Regional Affinities of Neandertal DNA With Living Humans Does Not Reject Multiregional Evolution

Points Made[edit | edit source]

Relethford argues that the idea of a mitochondrial Eve forgets to include migratory and inter-marriage patterns. He concedes we cannot predict, due to such considerations as the Migration Matrix theory, that while basic assumptions would lead one to the conclusion of genetic mixing in early pre-human groups, we cannot prove current Neanderthal contribution to the human mtDNA without knowledge of the initial contribution over ‘x’ amount of generations. He argues that the genetic diversity between Neanderthals and humans, while there, is not as significant to reasonably conclude that they were a separate species, more likely that they were a subspecies of humans given how Neanderthal mtDNA shows up only in isolated portions of the human population. [1]

The candelabra theory is invalid because the evidence to support the genetic connection between the subspecies is too substantial to ignore.

Methods[edit | edit source]

Relethford demonstrates his argument by modeling genetic evolution using migration matrix theory[1].

Results[edit | edit source]

While there is a great deal of genetic difference between neanderthal and human mtDNA,the differences are similar to that of the differences between different species and subspecies of chimpanzees. This suggests that Neanderthals were not likely an entirely different species, but just as likely a subspecies to humans. Regional comparison between mtDNA is not conclusive as it can be found in both replacement and multiregional models. Neanderthal DNA may have not affected human DNA to a very large degree even if there were in similar locations over an extended period time. This could be due to patterns of interaction and/or the amount of differences in DNA. However, any amount of neanderthal DNA in modern humans would suggest that most but not all recent human DNA came out of Africa. Gene change over time depends on the amount of genetic drift but also gene flow between groups. This is why some regional traits continue and some do not. However it is impossible to know what regional traits will continue and which ones will not[1].

I would like to pose the question about identifying which gene traits will continue and which genes will not. If there is a consistant drift with genes between groups, will that not bring regional traits as well? If not, then why can genes mutate within between groups and still maintain similar identifiers? The results of this should be investigated a little further to ensure that regional traits actually could potentially be traced. It is very interesting article but I would like to hear more information about taking the study a little further.Swats376 (talk) 02:07, 28 March 2012 (UTC)
The debate between whether or not human beings came from neanderthals originating previously from Africa, or in contrast, if neanderthals are a subspecies, is based on the axiom of the definition of what is a subspecies or the same species. It is important to think about the distinction we currently make between a species and a subspecies. The differences between what is a species and what is a subspecies is an arbitrary human made distinction that is highly subjective. There are current debates between scientists about animals that are alive today such as the American Hearing Gull [2] It seems premature to even have this debate when the amount of technology that this study is basing it's information off of is incapable of making the distinction between where a population originated and how much we mixed with neanderthal DNA. At the time the study was made it was only a debate over the definition of a term rather than hard scientific proof.

Alaxative (talk) 02:07, 28 March 2012 (UTC)

Through the theory of human evolution it would make sense that the neanderthals would be a predessor to humans. Genes can mutate over time to adapt to the surroundings. So with these mutations this would increase the changes of the matching the DNA to human species. There also is no conclusive proof that the neanderthals mixed with humans at any point in time, nor is it easily proven. However, there is similarities between humans and apes so the probability of evolution is quite high. Avatcher (talk) 02:28, 28 March 2012 (UTC)

References[edit | edit source]

  1. 1.0 1.1 1.2 Relethford, J. (2001) Absence of Regional Affinities of Neandertal DNA With Living Humans Does Not Reject Multiregional Evolution, American Journal of Physical Anthropology 115, 95–98