In Luca Ermini., et al’s. article “Major Transitions in Human Evolution Revisited: A Tribute to Ancient DNA” the authors explore the role that DNA (deoxyribonucleic acid) analysis, and specifically aDNA (ancient DNA), has played in reframing the theory of human migration out of Africa. The article addresses such areas as archaic hominins and their interbreeding with AMHs (anatomically modern humans), the path and timing of human migration through Eurasia and the Americas, and Megafauna extinction. All of these topics benefit from new insights and theories due to the role of aDNA analysis. The first area addressed by the article, is the new clarity brought to the human migration out of Africa. It has been a long accepted theory that archaic
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Two groups of archaic hominins have been genetically scrutinized. The Neanderthals are the extinct hominins with the most complete DNA analysis done so far. DNA research has also been performed upon the Denisovans. This research has given great insight into archaic hominin populations. The genetic data suggests that Neanderthals lived in smaller groups, perhaps 1/10th the size of AMHs, and had a high level of inbreeding while the Denisovans would form groups numbering closer to 1/5th of the size. The DNA evidence also shows that while interbreeding between AMHs and archaic hominins did occur, it was almost unheard of with Denisovans, outside a few isolated southeast Asian islands. However, with Neanderthals there is more evidence of genetic admixture, resulting in the modern human genome being comprised of approximately two percent Neanderthal DNA. However, successful interbreeding was a rare occurrence, perhaps just a few cases every century and resulting in hybrid male …show more content…
Many times there is a correlation between the arrival of humans and a rapid die off in the local megafauna. However, determinations of causality are often complicated by the concomitant occurrence of drastic climate change. While separating these factors can be difficult archaeologically, aDNA analysis can prove useful to that end. By analyzing the genetic diversity of a population, it can be more accurately inferred as to the overall population at a given time. This data seems to show that climate and human factors effected the various species of megafauna to a different degree. Some species where more closely tied to climate changes, while others suffered losses coinciding with the arrival of early humans. While most species showed some degree of correlation to both factors, the Woolly Rhino and Musk Ox extinction show no connection to early human
Two groups of archaic hominins have been genetically scrutinized. The Neanderthals are the extinct hominins with the most complete DNA analysis done so far. DNA research has also been performed upon the Denisovans. This research has given great insight into archaic hominin populations. The genetic data suggests that Neanderthals lived in smaller groups, perhaps 1/10th the size of AMHs, and had a high level of inbreeding while the Denisovans would form groups numbering closer to 1/5th of the size. The DNA evidence also shows that while interbreeding between AMHs and archaic hominins did occur, it was almost unheard of with Denisovans, outside a few isolated southeast Asian islands. However, with Neanderthals there is more evidence of genetic admixture, resulting in the modern human genome being comprised of approximately two percent Neanderthal DNA. However, successful interbreeding was a rare occurrence, perhaps just a few cases every century and resulting in hybrid male …show more content…
Many times there is a correlation between the arrival of humans and a rapid die off in the local megafauna. However, determinations of causality are often complicated by the concomitant occurrence of drastic climate change. While separating these factors can be difficult archaeologically, aDNA analysis can prove useful to that end. By analyzing the genetic diversity of a population, it can be more accurately inferred as to the overall population at a given time. This data seems to show that climate and human factors effected the various species of megafauna to a different degree. Some species where more closely tied to climate changes, while others suffered losses coinciding with the arrival of early humans. While most species showed some degree of correlation to both factors, the Woolly Rhino and Musk Ox extinction show no connection to early human