Posted on 01/31/2017 7:14:03 AM PST by Louis Foxwell
New DNA Study Shows Humans Bred With Unknown Species
Denisovans interbred with yet another extinct population that lived in Asia more than 30,000 years ago one that is neither human nor Neanderthal.
Updated genome sequences from two extinct relatives of modern humans suggest that these archaic groups bred with humans and with each other more extensively than was previously known.
The ancient genomes, one from a Neanderthal and one from a member of an archaic human group called the Denisovans, were presented at a meeting on ancient DNA at the Royal Society in London. The results suggest that interbreeding went on between the members of several ancient human-like groups in Europe and Asia more than 30,000 years ago, including an as-yet-unknown human ancestor from Asia.
What it begins to suggest is that were looking at a Lord of the Rings-type world that there were many hominid populations, says Mark Thomas, an evolutionary geneticist at University College London who was at the meeting but was not involved in the work.
The first published Neanderthal and Denisovan genome sequences revolutionized the study of ancient human history, not least because they showed that these groups bred with anatomically modern humans, contributing to the genetic diversity of many people alive today.
All modern humans whose ancestry originates outside of Africa owe about 2% of their genome to Neanderthals. Certain populations living in Oceania, such as Papua New Guineans and Australian Aboriginals, share about 4% of their DNA with Denisovans, members of a group named after a cave in the Altai Mountains in Siberia, Russia, where they were discovered. The cave contains remains deposited between 30,000 and 50,000 years ago.
At the meeting, however, David Reich, an evolutionary geneticist at Harvard Medical School in Boston, Massachusetts, who worked on those studies, said that the conclusions were based on low-quality genome sequences, riddled with errors and full of gaps. His team, along with collaborator Svante Pääbo at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, has now produced much more complete versions of the Denisovan and Neanderthal genomes matching the quality of contemporary human genomes. These high-quality Denisovan and Neanderthal sequences are both based on bones from the Denisova Cave.
The Denisovan genome indicates that the population got around: Reich said at the meeting that as well as interbreeding with the ancestors of Oceanians, they also bred with Neanderthals and the ancestors of modern humans in China and other parts of East Asia. Most surprisingly, Reich said, the genomes indicate that Denisovans interbred with yet another extinct population of archaic humans that lived in Asia more than 30,000 years ago one that is neither human nor Neanderthal.
The meeting was abuzz with conjecture about the identity of this unknown population of humans. We dont have the faintest idea, says Chris Stringer, a paleoanthropologist at the Natural History Museum in London, who was not involved in the work. He speculates that the population could be related to Homo heidelbergensis, a species that left Africa around half a million years ago and later gave rise to Neanderthals in Europe. Perhaps it lived on in Asia as well, says Stringer.
Note: this topic is from 1/31/2017. Thanks Louis Foxwell.
All modern humans whose ancestry originates outside of Africa owe about 2% of their genome to Neanderthals. Certain populations living in Oceania, such as Papua New Guineans and Australian Aboriginals, share about 4% of their DNA with Denisovans, members of a group named after a cave in the Altai Mountains in Siberia, Russia, where they were discovered. The cave contains remains deposited between 30,000 and 50,000 years ago.
In an analysis of the DNA of 1,000 individuals from 41 Pacific populations, an international team of scientists found strong evidence showing that Polynesians and Micronesians in the central and eastern islands had almost no genetic relationship to Melanesians, in the western islands like Papua New Guinea and the Bismarck and Solomons archipelagos. The researchers also concluded that the genetic data showed that the Polynesians and Micronesians were most closely related to Taiwan Aborigines and East Asians. They said this supported the view that these migrating seafarers originated in Taiwan and coastal China at least 3,500 years ago.
Studying human migrations, Hagelberg and her colleagues were analyzing hundreds of people from Papua-New Guinea and Melanesia. MtDNA samples on Nguna Island showed, as expected, three main population groups from colonizations over thousands of years. But in all three there also occurred a single mutation previously only known from one northern European. Hagenberg and her colleagues (1999) think it highly improbable for such a rare mutation event to occur repeatedly in such an isolated location. A more likely explanation would be recombination between different mitochondrial DNA types... Such findings, if upheld, seriously complicate the basis of using mtDNA to provide straightforward genetic lines, such as assumed in the Mitochondrial Eve hypothesis. The surprising homogeneity in the mtDNA of modern humans interpreted, in the Mitochondrial Eve hypothesis, as resulting from a recent common ancestor, may simply show the dilution of mutations caused by the recombination of mtDNA.
Some aboriginal Australians can trace as much as 11% of their genomes to migrants who reached the island around 4,000 years ago from India, a study suggests. Along with their genes, the migrants brought different tool-making techniques and the ancestors of the dingo, researchers say... It contradicts a commonly held view that Australia had no contact with the rest of the world between the arrival of the first humans around 45,000 years ago and the coming of Europeans in the eighteenth century... Irina Pugach, a postdoctoral researcher in Stonekings laboratory, discovered signs of the Indian migration by comparing genetic variation across the entire genomes of 344 individuals, including aboriginal Australians from the Northern Territory, highlanders from Papua New Guinea, several populations from Southeast Asian and India and a handful of people from the United States and China. Pugach confirmed an ancient association between the genomes of Australians, New Guineans and the Mamanwa -- a Negrito group from the Philippines. These populations diverged around 36,000 years ago, suggesting that they all descended from an early southward migration out of Africa.
New genetic evidence suggests Australia may have been populated by two separate groups of humans, one arriving via Papua New Guinea, the other via Indonesia, a researcher says.
Huge genetic diversity among Papuan New Guinean peoples revealed
Fri, Sep 15, 2017
Genetic diversity found to mirror linguistic and cultural diversity among Papuan New Guinean people.
http://popular-archaeology.com/issue/fall-2017/article/huge-genetic-diversity-among-papuan-new-guinean-peoples-revealed
The Neandertal Enigma"Frayer's own reading of the record reveals a number of overlooked traits that clearly and specifically link the Neandertals to the Cro-Magnons. One such trait is the shape of the opening of the nerve canal in the lower jaw, a spot where dentists often give a pain-blocking injection. In many Neandertal, the upper portion of the opening is covered by a broad bony ridge, a curious feature also carried by a significant number of Cro-Magnons. But none of the alleged 'ancestors of us all' fossils from Africa have it, and it is extremely rare in modern people outside Europe." [pp 126-127]
by James Shreeve
in local libraries
Agreed.
Scott does great sci-fi, but the Aliens/Prometheus story devolved to a disappointing conclusion in Covenant.
Don't be a stranger, we missed you, hope all is well.
New DNA Study Shows Humans Bred With Unknown Species
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my first husband?
Great find. Thank you for the repost after lo these many months.
I’ve seen pictures of the crazy terrain in Papua New Guinea...that entirely distinct populations could develop is totally not surprising. I don’t know who could get around that place without air travel!
that’s the one scene I did not understand in that movie
Thanks BroJoeK!
New DNA Study Shows Humans Bred With Unknown Species
Certainly some have.
I knew something was up when I got the results of my DNA ancestry test: 30% Irish, 50% Northern European, 20% Doberman. I have to say it was a little disappointing.
I know what you mean. Irish blood would be very depressing to me as well.
Prehistoric trailer trash ...
They had DEMOCRATS back then???
Good call, although if one person could walk over into a place, so could another...
:^)
My pleasure!
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