This is the sort of news that the leading frauds in the Creationist cults must be dreading, if they still have an hope of convincing their dupes that the Theory of Evolution is a theory in crisis, about to be overthrown and replaced by religious superstition. It is the news that leading evolutionary palaeontologist and geneticist, Professor Svante Pääbo, director of the Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany has been awarded a Nobel Prize for his work in the field of human evolution.
Far from being a theory in crisis, the Theory of Evolution is very much mainstream biomedical science, to the extent that the work Pääbo and his team are doing is central to our understanding of our recent history and how we relate to the archaic hominins that were our direct ancestors and the direct ancestors of other species of the Homo genus.
One of Pääbo's first major contributions to evolutionary biology was in sequencing Neanderthal genomes, then discovering that modern non-African Homo sapiens have at various times in recent history, had a significant ingression of Neanderthal DNA due to interbreeding between the two species. This horizontal gene transfer meant anatomically modern hominins acquired genes that had evolved in Neanderthals over a period of some 250,000 years, giving us significant adaptations to the cold, cloudy northern climates in Eurasia. Today, modern non-African humans have 2-4% Neanderthal DNA, most of it acquired about 40,000-60,000 years ago when the two species co-existed in Eurasia.
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Pääbo and his team then succeeded in sequencing the genome of a previously unknown hominin from a finger bone found in the Denisova Cave in Siberia and showed that this was a third distinct species of hominin, the Denisovans, who coexisted with Neanderthals, with whom they interbred extensively, and with H. sapiens with whom they also interbred. This led to the discovery that south East Asian and Melanesian people today have a significant proportion of Denisovan DNA, indicating frequent interbreeding as Homo sapiens spread out of Africa across central, southern and south-eastern Asia and into Indonesia, New Guinea and Australia.So What Did The Neanderthals Ever Do For Us?
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There is also a mysterious fourth hominin whose DNA has been found in Neanderthals and some Homo sapiens. Neanderthals and Denisovans were the descendants of an earlier migration out of Africa of an archaic hominin, probably H. erectus. H. sapiens are almost certainly the descendants of those H. erectus who stayed in Africa.
What this tells us is that for much of recent human history, we have co-existed with several other hominin species whose evolutionary divergence from us and each other was not sufficiently advanced to prevent interbreeding, probably because for most of the 250,000 years that Neanderthals had lived in Eurasia, during which the ancestors of H. sapiens lived in Africa, interbreeding was a rare event so there was no evolutionary pressure to either reintegrate into a single species or to establish barriers to hybridization.
Having said that, though, there is a recent explanation for the disappearance of Neanderthals which suggests that they were never exterminated but simply merged into the growing population of H. sapiens which quickly outnumbered them, to the extent that there is now more Neanderthal DNA in the world than there ever was prior to 40,000 years ago. When Homo sapiens came out of Africa, the period of co-existence was too short for barriers to hybridization to evolve, so for much of our recent history, the Homo complex of species behaved very much like a ring species of incompletely speciated regionals species and subspecies.
Creationist frauds now have the task of explaining to their credulous dupes why, if the TOE is a theory in crisis, one of its main exponents, whose work only makes any sense in the context of evolving hominin species, has been awarded the most prestigious prize in science - a Nobel Prize. We can now expect a proliferation of childish conspiracy theories as they seek to cope with the cognitive dissonance.
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