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Skomand
2018-02-06, 11:43
Most people are now familiar with the traditional "Out of Africa" model: modern humans evolved in Africa and then dispersed across Asia and reached Australia in a single wave about 60,000 years ago. However, technological advances in DNA analysis and other fossil identification techniques, as well as an emphasis on multidisciplinary research, are revising this story. Recent discoveries show that humans left Africa multiple times prior to 60,000 years ago, and that they interbred with other hominins in many locations across Eurasia.

A review of recent research on dispersals by early modern humans from Africa to Asia by researchers from the Max Planck Institute for the Science of Human History and the University of Hawai'i at Manoa confirms that the traditional view of a single dispersal of anatomically modern humans out of Africa around 60,000 years ago can no longer be seen as the full story. The analysis, published in the journal Science, reviews the plethora of new discoveries being reported from Asia over the past decade, which were made possible by technological advances and interdisciplinary collaborations, and shows that Homo sapiens reached distant parts of the Asian continent, as well as Near Oceania, much earlier than previously thought. Additionally, evidence that modern humans interbred with other hominins already present in Asia, such as Neanderthals and Denisovans, complicates the evolutionary history of our species.


Read more at: https://phys.org/news/2017-12-story-dispersal-modern-humans-eurasia.html#jCp

Question: Is there also evidence of the presence of human DNA in Neanderthal, Denisovan etc ?

Skomand
2018-02-06, 16:34
Here is something, not exactly a hybrid, but still a human with up to 9 per cent Neanderthal

https://www.the-scientist.com/?articles.view/articleNo/43354/title/Neanderthal-Human-Hybrid-Unearthed/

Neanderthal-Human Hybrid Unearthed

DNA from the 40,000-year-old bones of a modern human found in Europe contains Neanderthal genes.


DNA taken from a 40,000-year-old modern human jawbone from the cave Pestera cu Oase in Romania reveals that this man had a Neandertal ancestor as recently as four to six generations back.IMAGE, SVANTE PAABO, MAX PLANCK INSTITUTE FOR EVOLUTIONARY ANTHROPOLOGYBetween 35,000 and 45,000 years ago, modern humans spread throughout Europe. Around the same time, Neanderthals disappeared from the landscape—but not before interbreeding with Homo sapiens. Recent research has revealed that all non-Africans living today retain a genetic trace—1-3 percent of the genome—of Neanderthal ancestry. And 40,000 years ago, human genomes may have contained twice as much Neanderthal DNA, according to a study published today (June 22) in Nature.

Genetic material recovered from 40,000-year-old human bones unearthed in Romania harbors about 6-9 percent Neanderthal DNA, the study reports. Some of this DNA was contained in three relatively large chromosome segments, suggesting the individual had a Neanderthal ancestor only four to six generations back. “I think the conclusions are quite clear, and it’s really quite remarkable that they were lucky to find a hybrid that was so recent to be able to date it to a few generations back,” said Rasmus Nielsen, a University of California Berkeley population geneticist who was not involved with the work.

thetick
2018-02-06, 19:30
Below is the latest human tree from Dec 2017
https://i.pinimg.com/originals/de/c0/c7/dec0c797be86264d071b9cfc037ba239.jpg

And Vimeo link for "Chris Stringer: What’s New in Human Evolution? 5 December 2017"
https://vimeo.com/248446274

Reason1234
2018-02-06, 19:37
Question: Is there also evidence of the presence of human DNA in Neanderthal, Denisovan etc ?

Neanderthals and denisovans are human.

CWF
2018-02-06, 19:44
So the only change here is that some OOA dispersals may have begun as early as 120K years ago but the overwhelming push OOA was still about 60K years ago. Is that the understanding?

Also, many modern humans alive today have neanderthal input but I wouldn't call them hybrids. I don't get that.

Skomand
2018-02-06, 19:59
Neanderthals and denisovans are human. .....
Also, many modern humans alive today have neanderthal input but I wouldn't call them hybrids. I don't get that.

Nomenclature for a biological continuum is difficult and often simplified, but you know what is meant.

CWF
2018-02-06, 20:07
Nomenclature for a biological continuum is difficult and often simplified, but you know what is meant.

Scientific papers should not be engaging in a play on words. They need to be specific and clear about the definitions they use. I'm disgusted that as our technology advances we fail to follow appropriate protocols in formal communication. This would not have happened in scientific reporting decades ago.

For the record it seems you've also mixed Reason1234 's reply with mine but the point carries.

thetick
2018-02-06, 21:12
Neanderthals and denisovans are human.

Yes but there were far more archaic humans than just two. Currently three archaic humans are known to have contributed to human DNA, the two mentioned above and an previously unknown African lineage.