The Mating Habits of Early Hominins | TheScientist

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A newly sequenced Neanderthal genome provides insight into the sex lives of human ancestors.

A high-quality genome sequence obtained from a female Neanderthal toe bone reveals that the individual’s parents were close relatives and that such inbreeding was prevalent among her recent ancestors, according to a paper published today (December 18) in Nature. But the sequence also reveals that interbreeding occurred between Neanderthals and other hominin groups, including early modern humans.

“Did humans evolve like a constantly branching tree? A lot of people think so,” said Milford Wolpoff, a professor of anthropology at the University of Michigan, who was not involved in the study. “But there’s also been this thread of thought, by some people like me, that humans evolved more like a network, where there are different populations and they split and sometimes they come back together and they mate.” The new toe bone sequence data, he said, is “really important because it’s giving us good evidence that there’s been constant interbreeding between different human groups all through prehistory.”

The toe bone was found in a cave in Denisova, Siberia, where the conditions for DNA preservation are near-perfect. “The cave year-round has an average temperature of zero degrees Celsius and that’s probably helping to contribute to the preservation,” explained John Hawks, a professor of anthropology at the University of Wisconsin, who also did not participate in the study.

Indeed, the toe bone and its DNA were so well preserved that it was possible to obtain sequence data that “is on the same level, as far as quality goes, as many other modern human genomes,” said Kay Prüfer, an evolutionary geneticist from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, who led the study. “For every position in the genome we have on average 50 fragments covering it, which is amazing,” he said. Just how amazing? Previously sequenced Neanderthal genomes have average coverages of 0.5 to 1.3.

Also amazing, was the fact that the toe bone was Neanderthal at all. Previous bone and tooth samples found in the cave had yielded high-quality DNA sequences identified as belonging to a new and different group of hominins called the Denisovans, who were named after the location. “We were expecting that it [the toe] would be another Denisovan,” said Prüfer, “but, to our surprise, it wasn’t.”

Written By: Ruth Williams
continue to source article at the-scientist.com

4 COMMENTS

  1. Many features of these early hominids were similar. It seems they could all talk.

    http://news.discovery.com/human/evolution/neanderthals-talked-like-us-130711.htm
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    Neanderthals, like modern humans, likely communicated among themselves and with others using tonal languages.

    New research, published in the journal Frontiers in Language Sciences, presents strong evidence — genetic, fossil, archaeological and more — that modern speech and language existed among Neanderthals, Denisovans (a Paleolithic type of human), and early members of our own species.

    “Modern humans and Neanderthals and Denisovans are very similar genetically, and there are indications of interbreeding as well, strengthening this similarity,” lead author Dan Dediu told Discovery News, explaining that a gene involved in language and speech, FOXP2, is present in all three groups.

  2. the individual’s parents were close relatives and that such inbreeding was prevalent among her recent ancestors, according to a paper published today (December 18) in Nature. But the sequence also reveals that interbreeding occurred between Neanderthals and other hominin groups, including early modern humans.

    I’ve never doubted that interbreeding occurred amongst the three groups, and I have no doubt that there was much inbreeding between closely related individuals too, but I’m curious as to how much inbreeding there was and I want to know how Westermarck’s effect fits in with all of this. Anyone care to speculate?

  3. Maybe they just didn’t look different enough for each species to think – hey that’s another species lets mate…. It’s obvious that ancient humans didn’t know there were other human types in the world…maybe if you seen someone new …you would jump at the chance of new genetic input….that’s a biological drive….Inbreeding must have had to occur at times… but humans were migratory or nomadic so wandering would increase their chances of meeting new humans outside their own small bands of humans….

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