How man migrated out of Africa: Study sheds new light on the journey our ancestors took 100,000 years ago The first modern humans are thought to have left Africa up to 100,000 years ago Techniques for sequencing genomes of ancient ancestors are improving With this increased data, scientists need better ways to analyse their findings Now a new model could take us a step closer to understanding the journey of our ancestors
Mena: All the people on Earth needs to know that Black African people are the first people on Planet Earth. Black African people are the parents of all the different human races and Black African people are the owners and guardians of Planet Earth. Black people should be treated with respect by all the other races, Black people shouldnt be discriminated against and be kill by the other races.
When a racist White, Latino and Arab racist person are saying that a Black person is inferior they are ignorantly insulting themselves. It is like they are saying my mother and father are inferior. If Black people are inferior then White, Latino and Arabs are inferior to because you are the children of Black people. In reality there is only one race on planet earth the Human race aka the Black race and his subset or variation.
Scientists are bringing us a step closer to understanding the life-changing journey our ancestors took when they first moved out of Africa, with a new way to trace migration events published today. Map of the migration of humans out of Africa, based on mitochondrial DNA
Their model says there was a radiation of modern human populations shortly after leaving Africa, matching the work of archaeologists
Posts: 5374 | From: sepedat/sirius | Registered: Jul 2012
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In reality, the article does no such thing it fails to explain how Ust’-Ishim can represent the western ancestral Eurasian population, when this individual has no living descendants, and there appears to be two ancestral populations for the eastern Eurasians, since Tianyuan man is characterized by mtDNA B, while the Australasians mainly carry the mtDNA M clade.
As I pointed out elsewhere you can analyze genetic research papers via my “ A PROTOCOL TO EVALUATE POPULATION GENETICS PAPERS” https://www.academia.edu/12196288/A_PROTOCOL_TO_EVALUATE_POPULATION_GENETICS_PAPERS The Protocol provide a framework for analyzing and interpreting population genetics articles. Bayesian Statistics combines prior beliefs and sample DNA information to make inferences about the sample based on the researchers prior beliefs.
The authors claims that “Here, we report a model that provides a good statistical fit to allele-frequency correlation patterns among East Asians, Australasians, Native Americans, and ancient western and northern Eurasians, together with archaic human groups. The model features a primary eastern/western bifurcation dating to at least 45,000 years ago, with Australasians nested inside the eastern clade, and a parsimonious set of admixture events. “ These clades are represented by the Tianyuan individual (the eastern type) the Malta individual (the western type) .The evidence in the paper does not support this conclusion.
The sample used in the study were the archaic humanoids: Altai Neanderthals, and the Denisova; the western Eurasian clade was represented by Mal’ta 1 and , Ust’-Ishim individuals; indigenous populations from , New Guinea, Australia, Onge ( from the Andaman Islands), and the Ami (aboriginal Taiwanese) represented the eastern clade.
The basic error in this method is that the authors are comparing ancient and modern DNA, with the full knowledge that the ancient DNA, rarely corresponds to contemporary populations. In addition the authors use the date of the Ust’-Ishim individual as the terminal date for the separation of the eastern and western clades. Granted, the authors acknowledge that the Ust’-Ishim individual shows no admixture in Australasians . But this is not surprising , there are no living descendants of Ust’-Ishim. As a result, s/ he can not represent the point when the eastern and western clades separated .
Interestingly, the Tianyuan DNA, belongs to the mtDNA R macrohaplogroup, namely haplogroup B, in addition a deletion of a 9-bp motif (5′-CCCCCTCTA-3′, revised Cambridge reference sequence positions 8,281–8,289). This haplogroup is not carried by the indigenous populations from , New Guinea, Australia, Onge ( from the Andaman Islands), and the Ami (aboriginal Taiwanese) that represented the eastern clade in this study.
The authors of this article failed to discuss the Tianyuan DNA which also dates to 40kya, while the eastern sample used in the study are all modern. The failure to adequately discuss the Tianyuan DNA, makes the conclusion of the paper suspect, since the authors are claiming that the Australasians, represent the eastern clade, eventhough the Tianyuan individual is 45ky old. Moreover, the presence of the 9-bp motif clearly indicates an African influence among the Tianyuan.
Reference: Qiaomei Fu et al. DNA analysis of an early modern human from Tianyuan Cave, China. PNAS, published online before print January 22, 2013. http://www.pnas.org/content/110/6/2223.full
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