Relationship of Neanderthals to Modern Humans Relationship of Neanderthals to Modern Humans 11 November Genetics After extracting ancient DNA from the 40,year-old bones of Neanderthals, scientists have obtained a draft sequence of the Neanderthal genome, yielding important new insights into the evolution of modern humans.
The evidence we have of Neanderthal-modern human interbreeding sheds light on the expansion of modern humans out of Africa. These new discoveries refute many previous hypotheses in which anatomically modern humans replaced archaic hominins, like Neanderthals, without any interbreeding. However, even with some interbreeding between modern humans and now-extinct hominins, most of our genome still derives from Africa.
For many years, the only evidence of human-Neanderthal hybridization existed within modern human genes. Their findings are the first to show human gene flow into the Neanderthal genome as opposed to Neanderthal DNA into the human genome.
This data tells us that not only were human-Neanderthal interbreeding events more frequent than previously thought, but also that an early migration of humans did in fact leave Africa before the population that survived and gave rise to all contemporary non-African modern humans. We previously mentioned the lack of genetic contributions by Neanderthals into the modern human mtDNA gene pool.
There are several potential explanations for this. It is possible that there were at one point modern humans who possessed the Neanderthal mtDNA, but that their lineages died out.
It is also highly possible that Neanderthals did not contribute to the mtDNA genome by virtue of the nature of human-Neanderthal admixture.
While we know that humans and Neanderthals bred, we have no way of knowing what the possible social or cultural contexts for such breeding would have been.
Because mtDNA is passed down exclusively from mother to offspring, if Neanderthal males were the only ones contributing to the human genome, their contributions would not be present in the mtDNA line.
It is also possible that while interbreeding between Neanderthal males and human females could have produced fertile offspring, interbreeding between Neanderthal females and modern human males might not have produced fertile offspring, which would mean that the Neanderthal mtDNA could not be passed down.
Finally, it is possible that modern humans do carry at least one mtDNA lineage that Neanderthals contributed to our genome, but that we have not yet sequenced that lineage in either modern humans or in Neanderthals.
Any of these explanations could underlie the lack of Neanderthal mtDNA in modern human populations.Neanderthals were significantly shorter and stockier than modern humans, with much broader rib cages and pelvises. To give some perspective, the average height for a man in the USA is metres.
Conversely, based on the fossil records available, the average height for . Neanderthals were a separate species from modern humans, and became extinct (because of climate change or interaction with modern humans) and were replaced by modern humans moving into their habitat between 45, and 40, years ago.
Most of the attributes shared by modern humans are evident in the culture of Neanderthals including the use of tools and control of fire.
The differences as well as the similarities cited serve to support the existence of a close relationship between the two species. After extracting ancient DNA from the 40,year-old bones of Neanderthals, scientists have obtained a draft sequence of the Neanderthal genome, yielding important new insights into the evolution of .
Perhaps the early modern humans who left Africa 60, years ago were already genetically more similar to the Neanderthals—who had left hundreds of thousands of years before—than were the. Passionate encounters between ancient humans and their burly cousins, the Neanderthals, may have left modern people more prone to sneezes, itches and other allergies, researchers say..