By M.P. Pellicer | Stranger Than Fiction Stories The ability to map a person's DNA is popular to verify your ancestors, but what if your actual roots turn out not to be what you've been told for years, but somewhere totally different? The evolution of man has for many years been tied to the search for the supposed missing link. However this theory has come under scrutiny in recent years. Starting with the supposed six million years that it took for humans and chimps to evolve from the same ancestor, which is too short a time for this divergence to take place. The dates of fossil skulls, previously hailed as exact were later disregarded. Other proofs used for the "out of Africa" model (OoAM) of human evolution is not as ironclad as once thought. Many of these challenges stem from recent scientific papers on the human genome, mitochondrial DNA and Y-chromosomes. OoAM also referred to as the African replacement model, argues that modern human (Homo sapiens) evolved in East Africa about 200,000 years ago. Then about 120,000 years ago, these modern humans started to spread throughout the world. The main exodus from Africa is dated to about 70,000 years ago. They allegedly replaced "less advanced humans" such as Neanderthals in Asia, Europe and the Old World. This was supposed to have happened with little or no interbreeding. The alternative to OoAM is multi-regionalism which argues that ancestors of modern day human groups are human (Homo erectus) left Africa about two million years ago. They settled roughly where they are today, evolving throughout different regions. There was however interbreeding between these groups. Greg Jefferys, an Australian historian explains that: "The whole ‘Out of Africa’ myth has its roots in the mainstream academic campaign in the 1990′s to remove the concept of Race. When I did my degree they all spent a lot of time on the ‘Out of Africa’ thing but it’s been completely disproved by genetics. Mainstream still holds on to it." The academics most responsible for the OoAM theory with the common African mother named "Eve", were Professors Alan C. Wilson and Rebecca L. Cann. They did specify in their paper that placing Eve in Africa was just an assumption not an assertion. In 2012, the paper Re-Examing the "Out of Africa" Theory and the Origin of Europeoids (Caucasians) in the Light of DNA Genealogy confirmed the denial of any African ancestry in non-Africans. It does support the existence of a common ancestor, but this individual "would not necessarily be in Africa. In fact. it was never proved that he lived in Africa." Examination of 7,556 haplogroups resulted in the absence of any African genes. The researchers stated: "the finding that the Europeoid haplogroups did not descend from 'African' haplogroups A or B, is supported by the fact that bearers of the Europeoid, as well as all non-African groups do not carry either SNI’s M91, P97, M31, P82, M23, M114, P262". Their theory maintains that non-Africans and current Africans descended separately from a more ancient common ancestor. Also the OoAM proposes that there was little if any interbreeding between groups, which has been challenged by evidence from ancient DNA. Modern human and other human groups such Neanderthals and Denisovans interbred, proving they are the same species. A report issued in 2017, using evolutionary dating found that mitochondrial DNA (mtDNA) taken from a Neanderthal thigh bone from 124,000 years ago, indicated that African mtDNA genes were found in Neanderthals, but over 270,000 years ago. This puts modern humans in or near Europe long before they left Africa, or before they even evolved there. A Homo sapiens skull found in Jebel Irhoud, Morocco originally dated at 160,000 years ago, was reevaluated to be from 315,000 years ago. This means humans appeared in Africa 100,000 years earlier than thought, and in North Africa, not East Africa. Previously the earliest modern human fossils found outside of Africa were dated to 90,000 to 120,000 years ago. The human species has been found to contain at least 20% DNA from other other hominids such as Neanderthal, Denisovan, African archaic, Homo erectus and now possibly Hobbit (Homo floresiensis). It might be as high as 40%, but it has not been identified yet. Modern humans are the only one who survived, and their closest extinct relatives were the Neanderthals, who lived in Europe and Asia until they went extinct about 40,000 year ago, however the divergence from Neanderthals to modern human happened about 550,000 to 765,000 years ago. About 1.5 to 2.1 percent of the DNA of anyone outside Africa is Neanderthal in origin. Humanity, genetically speaking is a hybrid species that did not share the same hunter-gatherer ancestry in Africa.
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Stranger Than Fiction StoriesM.P. PellicerAuthor, Narrator and Producer Archives
November 2024
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