“An interesting aspect of the Denisova 11 genome is that it allows us to learn things about two populations — the Neanderthals from the mother’s side, and the Denisovans from the father’s side,” said co-author Dr. Fabrizio Mafessoni, from the Department of Evolutionary Genetics at the Max Planck Institute for Evolutionary Anthropology.

The researchers found that Denisova 11’s father, whose genome bears traces of Neanderthal ancestry, came from a population related to a later Denisovan found in the cave.

The mother came from a population more closely related to Neanderthals who lived later in Europe than to an earlier Neanderthal found in the cave, suggesting that migrations of Neanderthals between eastern and western Eurasia occurred sometime after 120,000 years ago.

“So from this single genome, we are able to detect multiple instances of interactions between Neanderthals and Denisovans,” said co-author Dr. Benjamin Vernot, also from the Department of Evolutionary Genetics at the Max Planck Institute for Evolutionary Anthropology.

“It is striking that we find this Neanderthal/Denisovan child among the handful of ancient individuals whose genomes have been sequenced,” said co-lead author Dr. Svante Pääbo, Director of the Department of Evolutionary Genetics at the Max Planck Institute for Evolutionary Anthropology.

“Neanderthals and Denisovans may not have had many opportunities to meet. But when they did, they must have mated frequently — much more so than we previously thought.”

Neanderthals and Denisovans are extinct groups of hominins that separated from each other more than 390,000 years ago. These two groups inhabited Eurasia — Neanderthals in the west and Denisovans in the east — until they were replaced by modern humans around 40,000 years ago. Now, a research team led by scientists at the Max Planck Institute for Evolutionary Anthropology has sequenced the genome of Denisova 11, a 50,000-year-old individual from Denisova Cave in Siberia, and discovered that she had a Neanderthal mother and a Denisovan father.

Image result for ‘Denisova 11’ Had Neanderthal Mother and Denisovan Father
Denisovans were probably dark-skinned, unlike the pale Neanderthals. The picture shows a Neanderthal man.
Image credit: Mauro Cutrona.

Before Neanderthal There Was Denisovan?

By James Donahue

Modern research in human DNA has uncovered some fascinating discoveries in ancient bone and tooth fragments dug up in a Siberian cave. It seems that the DNA of a much older humanoid, dubbed Denisovan, has been identified not only in the bone pieces, but even in the DNA of some contemporary humans, mostly in East Asia and even as far south as Australia.

What is especially interesting about the fossils found in that Siberian cave is that the bones of not only Denisovan, but Neanderthal and even Homo Sapiens, dating back an estimated 640,000 years, have all been found there. And some scientists are daring to imagine that these three types of humanoids not only co-existed, but did some inter-breeding, thus producing some interesting DNA strains turning up in research labs.

The physical features of the Denisovans are almost impossible to imagine because the only proof of their existence is found in a finger and toe bone, and one tooth uncovered in Siberia. Yet the thickness of the bone strongly suggests that the Denisovans were a hearty bunch, possibly similar to our concept of the Neanderthal. That their DNA appears more pronounced in a particular type of human today also suggests that they were dark skinned with black or dark hair and dark eyes.

While archaeologists have found the bones and skulls of a variety of other humanoid types in various parts of the world, the discovery of the Denisovan is a fascinating addition to the mix. This is because once their DNA was identified from the bones of an alleged pure strain in that Siberian cave, evidence of a mixture of that same DNA seems to be turning up in people throughout Asia, Europe and Africa. This suggests that the Denisovan was a relatively successful humanoid that appears to have been in existence long before the Neanderthal came on the scene, and remained here while Neanderthal and even Homo sapiens evolved.

The Neanderthals successfully existed on Earth for about 100,000 years. Did the Denisovans precede the Neanderthals? And if so, were they as successful? Indeed, the DNA from a 400,000-year-old femur bone found in Spain has been confounding researchers. They say the DNA appears to be closer to Denisovan than Neanderthal.

It also has been found that the Denisovan genome contains a component linked to a yet unknown hominin that appears to have existed at an even earlier period. Thus the history of primitive humanoids may date back for perhaps a million years or longer. And no, the DNA of these types still does not link those early folks to the apes.

All of this intensifies the mystery of just where we humans came from. That so-called “missing link” with the apes still remains elusive.

Indeed, a jawbone fragment from a primitive type of “ape-man” that walked upright an estimated 2.8 million years ago, was recently found by a research team working in East Africa. But getting a full picture of such creatures, what they looked like and how they lived remains a teasing part of the puzzle.

And none of this explains why there are so many different races of humans in existence on the planet today; how we evolved so differently and why our cultures are so unique from one another.

https://www.perdurabo10.net/denisovan.html

Scientists Produce Map of Neanderthal, Denisovan Ancestry in Present-Day Humans

Mar 29, 2016
by Enrico de Lazaro

Dr. David Reich from Harvard Medical School and his colleagues have produced a world map of Denisovan and Neanderthal ancestry in 120 diverse populations. Their analysis proposes that Denisovan admixture into humans occurred about 100 generations after Neanderthal admixture.

Dr. Reich and co-authors collected their data by comparing known Neanderthal and Denisovan gene sequences across more than 250 genomes from 120 non-African populations publically available through the Simons Genome Diversity Project.

The analysis was carried out by a machine-learning algorithm that could differentiate between components of both kinds of ancestral DNA, which are more similar to one another than to modern humans.

The results, published this week in the journal Current Biology, showed that individuals from Oceania possess the highest percentage of archaic ancestry and South Asians possess more Denisovan ancestry than previously believed.

This reveals previously unknown interbreeding events, particularly in relation to Denisovans.

“We developed methods that can disambiguate the locations of segments of Denisovan and Neanderthal ancestry in present-day humans and applied them to 257 high-coverage genomes from 120 diverse populations, among which were 20 individual Oceanians with high Denisovan ancestry,” the scientists explained.

“In Oceanians, the average size of Denisovan fragments is larger than Neanderthal fragments, implying a more recent average date of Denisovan admixture in the history of these populations.”

“We document more Denisovan ancestry in South Asia than is expected based on existing models of history, reflecting a previously undocumented mixture related to archaic humans.”

In contrast, Western Eurasians are the non-Africans least likely to have Neanderthal or Denisovan genes.

http://www.sci-news.com/othersciences/anthropology/map-neanderthal-denisovan-ancestry-present-day-humans-03738.html

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