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A new population analysis of Indigenous Australians and Papuans shows they can trace their origins back to the very first arrivals on the continent about 50,000 years ago.
Claims that Indigenous Australians are the most ancient continuous civilization on Earth have been backed by the first extensive study of their DNA, which dates their origins to more than 50,000 years ago.

Scientists were able to trace the remarkable journey made by intrepid ancient humans by sifting through clues left in the DNA of modern populations in Australia and Papua New Guinea. The analysis shows that their ancestors were probably the first humans to cross an ocean, and reveals evidence of prehistoric liaisons with an unknown hominin cousin.

Prof Eske Willerslev, an evolutionary geneticist who led the work at the University of Copenhagen, said: "This story has been missing for a long time in science. Now we know their relatives are the guys who were the first real human explorers. Our ancestors were sitting being kind of scared of the world while they set out on this exceptional journey across Asia and across the sea."

The findings appear in one of four major human origins papers published in Nature this week, which together give an unprecedented insight into how humans first migrated out of the African continent, splintered into distinct populations and spread across the globe.

Willerslev's findings, based on a new population analysis of 83 Indigenous Australians and 25 Papuans, shows that these groups can trace their origins back to the very first arrivals on the continent about 50,000 years ago and that they remained almost entirely isolated until around 4,000 years ago. "They are probably the oldest group in the world that you can link to one particular place," said Willerslev.

En route to Australia, early humans would have encountered a motley assortment of other roving hominin species, including an unknown human relative who has now been shown to have contributed around 4% to the Indigenous Australian genome. Previously, scientists have discovered that prehistoric couplings have left all non-Africans today carrying 1-6% of Neanderthal DNA.

Willerslev said the latest findings added to the view that Neanderthals and other now extinct hominins, traditionally portrayed as low-browed prehistoric thugs, were "in reality not particularly different" from our own ancestors.

Adding to this picture, a second study found that the advent of modern human behaviours around 100,000 years ago, indicated by cave art and more sophisticated tools, does not appear to have been accompanied by any notable genetic mutations.

"Your genome contains the history of every ancestor you ever had," said Swapan Mallick, a geneticist at Havard Medical School who led the analysis of the genomes of people from 142 distinct populations.

The study also suggests that the KhoeSan (bushmen) and Mbuti (central African pygmies) populations appear to have split of from other early humans sooner than this, again suggesting that there was no intrinsic biological change that suddenly triggered human culture.

"There is no evidence for a magic mutation that made us human," said Willerslev.

Chris Stringer, head of human origins at the Natural History Museum in London, said the findings would be controversial in the field, adding: "It either means that the behaviours were developed earlier, they developed these behaviours independently, they acquired them through exchanges of ideas with other groups, or the estimated split times are too old."

Willerslev's study also resolves the apparent discrepancy between genetic findings implying that Indigenous populations have been in Australia for tens of thousands of years and the fact that the languages spoken by these populations are only around 4,000 years old. "You see a movement of people spreading across the continent and leaving signatures across the continent," said Willerslev. "That is the time that this new language has spread. It's a tiny genetic signature. It's almost like two guys entering a village and saying 'guys, now we have to speak another language and use another stone tool and they have a little bit of sex in that village and then they disappear again."

Aubrey Lynch, an Indigenous elder from the Goldfields area, said: "This study confirms our beliefs that we have ancient connections to our lands and have been here far longer than anyone else."

http://www.theguardian.com/australia-news/2016/sep/21/indigenous-australians-most-ancient-civilisation-on-earth-dna-study-confirms

Not sure why this jumped out at me from this interesting
article, but I gather the African-origin people share NO
Neanderthal DNA? I wonder why when they were so predominant
during that time.

i'm guessing the neanderthals were a lot dumber than early humans.. i've read that they were pretty much "blended in" with our ancestors, by ways of mating and wars...

and I thought we all came from Scotland

Ya, smaller brains.
But Europe was not that far from Africa, just seems strange that DNA passed down through every race except African.

I mean they made it to New Zealand and Papua.

Very nice article,and it just goes to show how our scope of knowledge expands with every new discovery. When you think about how many people have devoted their lives to putting this huge jig-saw puzzle of our history together,it is expansive in itself. Alfred Wallace,Darwin,The Leaky family,and many others have spent their lives in gathering these discoveries.
Not long ago,I removed an early american artifact from a riverbank near me. I couldn't help but ask myself,Who was this person who made and used this tool? Were they like me? Did they have the same needs and desires? How did their emotions run? were they happy and grateful,or were they competing for ground? Did they laugh a lot,or was life too hard to have much room for humor? Somehow,and in many ways,I think we still have a lot in common with our paleolithic ancestors,and we still have a lot to learn about who we are,and what we are becoming.

there's some chatter about maybe humans originated in China, not Africa...but i think it was more towards the middle east, since they have the oldest "modern" civilization to date..

So true, Moe has crazy-good articles on stuff like this.

one theory is that light skinned people evolved from dark skinned peoples... as they moved away from Africa into cooler climates, their skin lightened... maybe the true Africans never interacted with neanderthals, making their DNA more "pure"... just a guess, i really have no idea...

Ty, food for thought :-)

I think that National Geographic has mapped earliest DNA sources and traced the origins and descendant migrations world wide. Pretty interesting.

If you want to get the most from this, I recommend a couple of things to keep in mind or think about:

* first, the headline is potentially a little misleading. This study didn't decide that the Australians were the oldest CIVILISATION, it decided that they were the least genetically integrated peoples. Once they came to inhabit Australia, it appears that other waves of migration did NOT follow them there, as happened most everywhere else.

* this also suggests that this is informative of how easy or difficult it was for humans to traverse the oceans at various times. It may indicate that there were land bridges to the area 50,000 years ago, which were never renewed once they gave way soon after that time.

* the finding of Neanderthal DNA in many places, doesn't mean that THEY traveled that extensively, it means only that people carrying that DNA traveled.

no, the headline said aboriginals were the oldest confirmed peoples that settled in one place... do you just like to argue about everything?

Moe, don't you know? He's a genius, he knows everything.

yea, i guess i forgot...

You always post good stuff, Moe.
Thank you.

thank you, miss rose...

Since you apparently aren't seeing the same page I am, here is the title of this thread:



So. Are you going to withdraw your latest erroneous insult?

look at the title of the webpage, and tell me how thats gunna fit in here... in all your infinite wisdom, i'm sure you know we can only make the title so long... as far as "insults" go, go whine to the mods...

Ancient human migrations out of Africa may have been driven by wobbles in Earth's orbit and tilt that led to dramatic swings in climate, a new study finds.

Modern humans first appeared in Africa about 150,000 to 200,000 years ago. It remains a mystery as to why it then took many millennia for people to disperse across the globe. Recent archaeological and genetic findings suggest that migrations of modern humans out of Africa began at least 100,000 years ago, but most humans outside of Africa most likely descended from groups who left the continent more recently — between 40,000 and 70,000 years ago.

Previous research suggested that shifts in climate might help explain why modern human migrations out of Africa happened when they did. For instance, about every 21,000 years, Earth experiences slight changes to its orbit and tilt. These series of wobbles, known as Milankovitch cycles, alter how much sunlight hits different parts of the planet, which in turn influences rainfall levels and the number of people any given region can support.

Now scientists have developed a new computer simulation of Earth to pinpoint how these changes in orbit and solar radiation levels might have affected rainfall, temperature, sea levels, glacial ice, vegetation, carbon dioxide levels and global modern human migration patterns over the past 125,000 years. The researchers noted that this model's predictions agree well with previous findings regarding ancient climates.

The model suggests that modern humans dispersed from Africa in multiple waves across the Arabian Peninsula and the area known as the Levant, the eastern Mediterranean region that includes Israel and Syria. These results closely align with previous estimates garnered from archaeological and fossil data of when modern humans arrived in areas such as the Middle East, Europe, Asia, Australia and the Americas.

"Earth's wobble with a periodicity of 21,000 years played a huge role in our dispersal across the planet and most likely also in our evolution and adaptation," said study lead author Axel Timmermann, a climate researcher at the University of Hawaii at Manoa. "If the climate had been constant over the past 125,000 years, we would have evolved in a very different way."

Specifically, the researchers found that intensified rainfall in northern Africa, the Arabian Peninsula and the Levant would have generated habitable green corridors for modern humans to migrate through the Sahara and Arabian deserts. These corridors would have been open during four distinct times — about 106,000 to 94,000 years ago; 89,000 to 73,000 years ago; 59,000 to 47,000 years ago; and 45,000 to 29,000 years ago — "enabling Homo sapiens to leave northeastern Africa and embark onto their grand journey into Eurasia, Australia and the Americas," Timmermann told Live Science.

The model suggests these migrations were not one-way in nature away from Africa, "as is often portrayed in schematics," Timmermann said. "A green migration corridor between Africa and the eastern Mediterranean meant that Africans were migrating into Eurasia, and Eurasians were moving into Africa. The backflow of Homo sapiens into certain regions and the corresponding backflow of genes may be crucial for understanding who we are, why we are, where we are."

The model also suggests that modern humans should have arrived nearly simultaneously in southern China and Europe about 80,000 to 90,000 years ago. However, the oldest-known modern human fossils in southern China predate the oldest-discovered modern human fossils in Europe by about 35,000 to 40,000 years. The researchers proposed that the slow entry of modern humans into Europe might have been due to Neanderthals there.

In the future, "I am planning to include Neanderthals in our computer model" and account for factors such as interbreeding, cultural exchange and competition over food, Timmermann said.

Timmermann and his colleague Tobias Friedrich at the University of Hawaii at Manoa detailed their findings in the Sept. 22 issue of the journal Nature.

http://www.livescience.com/56188-humans-left-africa-due-to-earth-wobbles.html