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Old 9th February 2018, 08:39 AM   #161
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Sorry, wrong thread!
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Old 16th March 2018, 12:15 AM   #162
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Modern humans interbred with Denisovans twice in history.

Quote:
Modern humans co-existed and interbred not only with Neanderthals, but also with another species of archaic humans, the mysterious Denisovans. While developing a new genome-analysis method for comparing whole genomes between modern human and Denisovan populations, researchers unexpectedly discovered two distinct episodes of Denisovan genetic intermixing, or admixing, between the two.
They found some Denisovian DNA in East Asians that is different from the Denisovian DNA found in South Asians and Papuans.
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Old 16th March 2018, 09:43 AM   #163
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Originally Posted by UnrepentantSinner View Post
My guess, based on previous experience with Magz is - whites, Jews and mud people.
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Old 20th March 2018, 06:37 AM   #164
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Originally Posted by UnrepentantSinner View Post
My guess, based on previous experience with Magz is - whites, Jews and mud people.
No!!! Not geologists...
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Old 20th March 2018, 02:21 PM   #165
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Originally Posted by catsmate View Post
No!!! Not geologists...
He could mean brickmakers. Or natural beauty therapists...
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Old 9th April 2018, 11:56 AM   #166
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Finger bone points to early human exodus

Originally Posted by BBC News
New research suggests that modern humans were living in Saudi Arabia about 85,000 years ago.

A recently discovered finger bone believed to be Homo sapiens was dated using radio isotope techniques.

This adds to mounting evidence from Israel, China and Australia, of a widespread dispersal beyond Africa as early as 180,000 years ago.

Previously, it was theorised that Homo sapiens did not live continuously outside Africa until 60,000 years ago...
http://www.bbc.com/news/science-environment-43700703
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Old 9th April 2018, 12:00 PM   #167
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Was he flipping the bird?
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Old 30th January 2020, 10:32 PM   #168
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And now.....

African populations also have Neanderthal DNA!

A new computational DNA analysis method called IBDmix was used to analyze DNA. IBD stands for Identity By Decent and the principle is very simple. Genomes are compared and identical IBD segments identified, the more and the longer the segments the more recent the common ancestor shared. This is cool because it does not rely on a reference genome as does previous methods. African DNA was used as a reference because it was assumed it does not contain any Neanderthal DNA due to geographical isolation.
What they found was amazing and totally gels with a bunch of archeological finds. It turns out things were complicated and confusing because Neanderthals also have our DNA in their genomes!
There was an early Homo sapiens exodus from Africa before 100,000 years ago, that did not persist, but blended in with the Neanderthals, leaving traces in their DNA. Then some time between 100,000 and 50,000 years ago there were Neanderthal migrations back to Africa, introducing not only Neanderthal DNA to African populations, but also some of the earlier Homo sapiens DNA.

Neanderthal ancestry also in African populations
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Old 30th January 2020, 10:48 PM   #169
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Originally Posted by Cheetah View Post
And now.....


African populations also have Neanderthal DNA!


A new computational DNA analysis method called IBDmix was used to analyze DNA. IBD stands for Identity By Decent and the principle is very simple. Genomes are compared and identical IBD segments identified, the more and the longer the segments the more recent the common ancestor shared. This is cool because it does not rely on a reference genome as does previous methods. African DNA was used as a reference because it was assumed it does not contain any Neanderthal DNA.
What they found was amazing and totally gels with a bunch of archeological finds. It turns out things were complicated and confusing because Neanderthals also have our DNA in their genomes!
There was an early Homo sapiens exodus from Africa before 100,000 years ago, that did not persist, but blended in with the Neanderthals, leaving traces in their DNA. Then some time later there were Neanderthal migrations back to Africa, introducing not only Neanderthal DNA to African populations, but also some of the earlier Homo sapiens DNA.

Neanderthal ancestry also in African populations
I have been waiting for this one a while now. It pretty much seals the deal regarding modified multiregional.
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Old 30th January 2020, 11:06 PM   #170
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Originally Posted by Red Baron Farms View Post
I have been waiting for this one a while now. It pretty much seals the deal regarding modified multiregional.
You mean 'seals the fate'?
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Old 30th January 2020, 11:12 PM   #171
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Originally Posted by Cheetah View Post
And now.....

African populations also have Neanderthal DNA!

A new computational DNA analysis method called IBDmix was used to analyze DNA. IBD stands for Identity By Decent and the principle is very simple. Genomes are compared and identical IBD segments identified, the more and the longer the segments the more recent the common ancestor shared. This is cool because it does not rely on a reference genome as does previous methods. African DNA was used as a reference because it was assumed it does not contain any Neanderthal DNA due to geographical isolation.
What they found was amazing and totally gels with a bunch of archeological finds. It turns out things were complicated and confusing because Neanderthals also have our DNA in their genomes!
There was an early Homo sapiens exodus from Africa before 100,000 years ago, that did not persist, but blended in with the Neanderthals, leaving traces in their DNA. Then some time between 100,000 and 50,000 years ago there were Neanderthal migrations back to Africa, introducing not only Neanderthal DNA to African populations, but also some of the earlier Homo sapiens DNA.

Neanderthal ancestry also in African populations
Oh, dear! What will all the white nationalists do now ...
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Old 30th January 2020, 11:45 PM   #172
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Originally Posted by Cheetah View Post
You mean 'seals the fate'?
The evidence is shifting more and more towards multiregional as time goes forward and genetic evidence is collected.

Remember, originally the multiregional theory used only morphology and even that was highly controversial. And for a while we even had a more strict OOA and total replacement being the strong consensus... until very recently ...

That cats so far out of the bag I never see it going back in.

But looking forward all we would need for an almost complete multiregional is a continuation of studies similar to this showing mixtures every 50K-100K all the way back to the first OOA event from erectus
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Old 31st January 2020, 12:12 AM   #173
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Originally Posted by Red Baron Farms View Post
The evidence is shifting more and more towards multiregional as time goes forward and genetic evidence is collected.
Afraid not. Not as I understand the multiregional hypothesis as it was presented until it died on it backside a few decades ago. There is no doubt, genetically, that Homo sapiens originated in Africa, and left there quite recently. The genetic evidence for that is undeniable. That some of our ancestors encountered and bred with other sub-species of Homo along the way, says nothing about multiregionalism as I understand it.
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Old 31st January 2020, 12:38 AM   #174
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Originally Posted by jonesdave116 View Post
Afraid not. Not as I understand the multiregional hypothesis as it was presented until it died on it backside a few decades ago. There is no doubt, genetically, that Homo sapiens originated in Africa, and left there quite recently. The genetic evidence for that is undeniable. That some of our ancestors encountered and bred with other sub-species of Homo along the way, says nothing about multiregionalism as I understand it.
Well here is this:
Quote:
"Recent human evolution is an area of great controversy. There is
general agreement that the human lineage evolved in Africa, and
then spread to southern Eurasia as Homo erectus. After Homo erectus
spread out of Africa, the out-of-Africa replacement model posits
that populations in Africa, Europe and Asia had little genetic
contact and evolved independently
, with anatomically modern
humans evolving only in Africa. After the evolution of modern humans in Africa, a second expansion occurred out of Africa about
100,000 years ago that resulted in the global replacement and
genetic extinction of nonmodern human populations by anatomically modern humans."

Out of Africa again and again
Alan R. Templeton
Department of Biology, Washington University, St Louis, Missouri 63130-4899, USA
and so finding more and more interbreeding falsifies that and moves the spectrum towards multiregional.

Of course originally the multiregional proponents only had some morphology that seemed to suggest that certain traits found uniquely in Asian H erectus were indeed still uniquely found in Asian modern populations, suggesting instead of total replacement, a continuity that went back all the way to the original out of Africa populations, and that requires that archaic populations being capable of interbreeding with the modern recent out of Africa wave.

And genetic studies are showing that this did indeed happen, and each breakthrough shows more and more. In particular I was waiting on this one showing movement INTO Africa as well, because it then basically seals the deal that all these "archaic forms" were indeed just regional variations of the same species that had frequent gene flow rather than simply replacement of populations without interbreeding.
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Old 31st January 2020, 02:48 AM   #175
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The mixing with neanderthals happened after anatomically modern Homo sapiens had already evolved, so I'm not seeing the connection here.
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Old 31st January 2020, 05:04 AM   #176
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As everyone is saying the multiregional hypothesis is truly dead.


Originally Posted by Red Baron Farms View Post
"Recent human evolution is an area of great controversy. There is
general agreement that the human lineage evolved in Africa, and
then spread to southern Eurasia as Homo erectus. After Homo erectus
spread out of Africa, the out-of-Africa replacement model posits
that populations in Africa, Europe and Asia had little genetic
contact and evolved independently, with anatomically modern
humans evolving only in Africa."
and so finding more and more interbreeding falsifies that and moves the spectrum towards multiregional.
No.
Homo erectus had already made it out of Africa long before 2 mya and whatever species they evolved into in Europe and Asia (H antesessor, Pekin and Java man, H floriences etc.) appear not to be part of our evolutionary linage.

I could make a pretty good argument that Homo heidelbergensis were actually the first real humans and that Neanderthals, Denisovians, H sapiens and whatever other archaic humans were in the mix at the time are only subspecies of H heidelbergensis.

H heidelbergensis probably made it out of Africa multiple times and between 700,000 and 300,000 ya had given rise to a bunch of geographically isolated subspecies. One of those in Africa became H sapiens, in Europe and Asia Neanderthals, Denisovians and more.
Just because there was a little genetic mixing with Neanderthals, Denisovians and other species that originated out of Africa (all evolving from Homo heidelbergensis though) doesn't in any way mean that H sapiens originated separately in different locations.
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Old 31st January 2020, 01:36 PM   #177
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Originally Posted by Cheetah View Post
Just because there was a little genetic mixing with Neanderthals, Denisovians and other species that originated out of Africa (all evolving from Homo heidelbergensis though) doesn't in any way mean that H sapiens originated separately in different locations.
Agreed. Not "just because". However, take H. antecessor, a proposed chronospecies between H. erectus (c. 1.9–1.4 Mya) and H. heidelbergensis (c. 0.8–0.3 Mya)

H. antecessor is one of those species you claim are not part of our evolutionary linage. (Something only ten years ago was declared/known about Neanderthals BTW)

Yet H. antecessor contains a mixture of modern and primitive traits. Some traits are indistinguishable from H. ergaster (a homo sapiens ancestor from Africa). While other traits are indistinguishable from H erectus that left Africa a million years earlier and H heidelbergensis half a million years later.

I would claim a case could be made that just as modern humans left Africa and interbred with Neanderthal, Denisovan and other archaic descendants of H heidelbergensis , so too H. ergaster left Africa and interbred with the archaic descendants of the first H erectus migration out of Africa.... and so on and so forth in such a way as there was some continuity going all the way back 2 Mya

ETA my main argument would be that once our human ancestors developed the technology to migrate out of Africa and thrive, they never became isolated enough to completely diverge 100% again. There was a continuity of gene flow to greater or lessor degree, but never so little that some traits couldn't flow all the way from ancient Asian H erectus to present H sapiens and vice versa (ancient African H erectus to present H sapiens).
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Old 31st January 2020, 02:59 PM   #178
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Originally Posted by Red Baron Farms View Post
Agreed. Not "just because". However, take H. antecessor, a proposed chronospecies between H. erectus (c. 1.9–1.4 Mya) and H. heidelbergensis (c. 0.8–0.3 Mya)

H. antecessor is one of those species you claim are not part of our evolutionary linage. (Something only ten years ago was declared/known about Neanderthals BTW)

Yet H. antecessor contains a mixture of modern and primitive traits. Some traits are indistinguishable from H. ergaster (a homo sapiens ancestor from Africa). While other traits are indistinguishable from H erectus that left Africa a million years earlier and H heidelbergensis half a million years later.

I would claim a case could be made that just as modern humans left Africa and interbred with Neanderthal, Denisovan and other archaic descendants of H heidelbergensis , so too H. ergaster left Africa and interbred with the archaic descendants of the first H erectus migration out of Africa.... and so on and so forth in such a way as there was some continuity going all the way back 2 Mya

ETA my main argument would be that once our human ancestors developed the technology to migrate out of Africa and thrive, they never became isolated enough to completely diverge 100% again. There was a continuity of gene flow to greater or lessor degree, but never so little that some traits couldn't flow all the way from ancient Asian H erectus to present H sapiens and vice versa (ancient African H erectus to present H sapiens).
Sorry, not buying it. Undoubtedly, and as proven, there was interbreeding of incoming sapiens with the archaic humans they encountered. It would be surprising if there weren't. However, if sapiens evolved essentially from these archaic forms, at various places around the planet, one would not expect to see the difference, genetically speaking, between a European and a Japanese to be lower than much closer (in terms of distance) human groups in the homeland. i.e. Africa. In other words, the genetic diversity in Africa is greater that that between all non-African populations. Which very strongly suggests that all non-African sapiens can trace their origin to a small group that left Africa relatively recently. Were the multiregional hypothesis correct, I would expect to see far greater genetic diversity between all the non-African populations. As much as we see between different African populations today. We do not see that.
And of course there would have been back-migration to Africa. Again, it would be astonishing if there weren't. That some of that back-migration included individuals who carried Neanderthal genes is hardly surprising. What is indisputable, is that the amount of Neanderthal genes seen in Africa is as close to zero as makes no difference, whilst being much higher among non-Africans. Again implying that all non-Africans left that continent relatively recently.
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Old 2nd February 2020, 01:07 PM   #179
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Originally Posted by Cheetah View Post
You mean 'seals the fate'?
Neither "seals the deal" or "seals the fate".
Neanderthal ancestry also in African populations is about interbreeding between Homo Sapiens and Neanderthal . It is new evidence that some Neanderthal population or Homo Sapiens with Neanderthal genes migrated into Africa.

Multiregional origin of modern humans. The original hypothesis is fairly well dead. The "weak" multiregional origin theory is still alive and being researched.

Out of Africa again and again by Alan R. Templeton is a paper written in 2002. It is evidence against a single out-of-Africa event, thus the title. This gave the possibility of archaic populations of Homo in different regions which could interbreed with the Homo Sapiens migrations out of Africa. It may be that this paper was a spur to the change from 'classic' to 'weak' multiregional origin theory in 2003.
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