[eddyzh]

Makes a huge claim at the start.

>"The huge gap between those ages could change our understanding about how humans spread across the world. If the ancestors of today’s non-Africans didn’t sweep across other continents until 47,000 years ago, then those older sites must have been occupied by earlier waves of humans who died off without passing down their DNA to the people now living in places like China and Australia."

But at the end gets a bit more balanced

>"He Yu, a paleogeneticist at Peking University in Beijing who was not involved in either study, said that the mystery wouldn’t be solved until scientists find DNA in some of the ancient Asian fossils. “We still need early modern human genomes from Asia to really talk about Asia stories,” Dr. Yu said."

This puzzle is still missing key elements.

[jl6]

It doesn’t seem like an outlandish claim that many waves of humans tried and failed to colonize the world, until one succeeded. I would find it harder to believe that the first to leave Africa got it right first time.

[defrost]

One question raised by a researcher in the article:

    Dr. Skoglund also said it would be strange for non-African ancestors to have arisen about 47,000 years ago while modern humans in Asia and Australia dated back 100,000 years. The sites in question could have been incorrectly dated, he said, or people could have reached Asia and Australia that long ago, only to die out.

Doesn't mesh well with genetic studies from Australia that show a long history of relatively stable regionalism within Australia (with some still unresolved mixing from Denisovan ancestors.

see:

(2016) https://www.abc.net.au/news/science/2016-09-22/world-first-s...

(2017) https://www.nature.com/articles/nature21416

etc.

[shellfishgene]

I doubt it's correct to assume groups of humans in Africa one day decided to 'colonize' another place and walked thousands of kilometers to settle down elsewhere. It's probably more like a slow expansion (and reduction) of the settled area, no?

[enkid]

I don't think a group of people living somewhere for thousands of years would be "getting it wrong." You're embedding an assumption that evolution has been working toward an end goal of getting humans to spread globally, which isn't how evolution works.

[h0l0cube]

I think the claim is that earlier founders did colonize the world before the final group left and also colonized the world. Land bridges disappeared as the last ice age came to a close, making later attempts more difficult

[tetris11]

I think they just walked to other places as and when the climate changed. Some adapted and stayed, others moved the greener pastures. This slow and climate-driven process can hardly be described as colonization.

[kspacewalk2]

And their failure doesn't mean they're completely absent from our genome.

[mapt]

It doesn't seem like an outlandish possibility.

That's distinct from making a claim, an assertion with supporting evidence.

To make a claim, we would want evidence, and the evidence here would be a genetic isolation (lack of chronological overlap, synonymous with lack of interbreeding) of ancient Asian humans from ancient African humans. This requires sequencing a lot of ancient Asian DNA, which seems not to have happened yet. We barely have a cohesive evidence supported grasp of Neanderthal interactions in Europe, but are gradually updating to support more and more absorption by interbreeding.

[miniwark]

The view of the chinese researcher is in line with the Multiregional origin hypothesis of modern humans, where asian humans may partially come from asia. So his reply is not surprising.

https://en.wikipedia.org/wiki/Multiregional_origin_of_modern...

Instead, the article follow the Out of Africa origin, and therefore did not explain the old chineses and autralian remains. The article try to explain this by saying than it's because this lines where extincts or than the dates are wrong, but this explanations are not very convincing.

[bee_rider]

What’s the most significant difference between the theories? The Wikipedia article says:

> “The primary competing scientific hypothesis is currently recent African origin of modern humans, which proposes that modern humans arose as a new species in Africa around 100-200,000 years ago, moving out of Africa around 50-60,000 years ago to replace existing human species such as Homo erectus and the Neanderthals without interbreeding.[5][6][7][8] This differs from the multiregional hypothesis in that the multiregional model predicts interbreeding with preexisting local human populations in any such migration.”

But it is a somewhat weird quote in the Wikipedia article. They’ve got the whole thing in quotes with multiple citations (so it isn’t clear which citation the quote comes from), it isn’t attributed to anybody in particular, and it doesn’t seem to be a very accurate description of what I though the consensus was, at least. (It is widely believed that humans interbred with other hominids, right?)

[PittleyDunkin]

Am I missing something? Surely Europe is the same continent as Asia. Why wouldn't people just walk over? It seems reasonable to assume that if evidence exists on one side of the continent that it'd imply existence on the other side, too. If anything you'd need a theory why they failed to spread to formulate interesting discussion!

[hackinthebochs]

The Steppes are a natural barrier between East and West until the point where technology caught up to make it passable.