Opinion Article Example | Topics and Well Written Essays - 1500 words

Opinion - Article Example Genetic analysis using the most modern methodologies alone can help recreate the ancestral relation of modern man to each of its ancestors and help track down the origin of man. Introduction Based on the study of fossils by paleoanthropologists, it was established that Homo Erectus was present in East Africa nearly 2 million years ago (Pic1). Homo Erectus is known to have large cranial capacity and was conversant with hunting however was still unfamiliar with methods of building or agriculture. Most scientists believe that Homo Erectus moved out of Africa where they slowly developed into Neanderthals and other homo erectus groups. Out of the two proposed hypotheses for the origin of man, the out-of-Africa hypothesis, though debated upon, is largely supported with fossil evidences and genetic analysis. According to the article selected, genetic analysis of homo sapiens or the modern man shows that Homo sapiens descended from Homo erectus in Africa nearly 200,00 years ago. Post this, H omo sapiens moved out of Africa to different places such as Asia, Europe and later to Australia and America. Thus, gradually Homo Sapiens are said to have replaced all the Homo Erectus according to the out-of-Africa theory. One of the most important evidences to support this is mt DNA analysis of African and non-African populations. Mitochondrial analysis clearly reveals that the mt DNA (mitochondrial Dna), which is the DNA extracted from mitochondria, sequence diversity is greater among Africans than that of non-Africans thereby establishing the point that the ancestors of Homo Sapience must have had diverged in the African region. DNA sequences obtained from Y-chromosome or mitochondria support the fact that the roots of the modern man are based in east Africa. DNA analysis also establishes that large scale migration of Homo sapiens occurred out of the East African region to Ethiopia, Eurasia, Asia etc More advanced genetic analytic studies like that of single nucleotide polymorph ism (SNP) or microsatellite study also supports the fact that the modern man originated in Africa and then spread to other parts of the world.However, there are several unanswered questions regarding this migration and the out-of-Africa hypothesis. BODY 1. Mark Stoneking and Johannes Kruase compared the DNA sequence of Neanderthal to that of modern day mani. The mt DNA of the Neanderthals differed vastly from that of Homo sapiens. Newer studies suggest admixture i.e. interbreeding of species where genetic material exchanges are seen. The out-of-Africa theory was tested according to which â€Å"a single dispersal from Africa followed by separate migrations from this ancestral non-African source population, and this scenario receives the strongest support from the data (P = 0.74)† (Stoneking & Kruase). I feel that the previous out-of-Africa theory needs to be modified since genome analysis provides a direct relationship according to which it is seen that Neanderthals and Deniso van genomes diverged from hominin genome. After this the sister groups i.e. Neanderthal and Denisovan diverged and migrated as admixtures while the rest of the hominins in Africa gradually became the modern man. Therefore, the prior belief that Homo sapiens evolved entirely in Africa before migrating to other places is modified into the fact that hominins diverged into groups which interbred and this admixture migrated to other places