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NetNomad
03-30-2019, 06:00 PM
A dispersal of Homo sapiens from southern to eastern Africa immediately preceded the out-of-Africa migration

Abstract
Africa was the birth-place of Homo sapiens and has the earliest evidence for symbolic behaviour and complex technologies. The best-attested early flowering of these distinctive features was in a glacial refuge zone on the southern coast 10070 ka, with fewer indications in eastern Africa until after 70 ka. Yet it was eastern Africa, not the south, that witnessed the first major demographic expansion, ~7060 ka, which led to the peopling of the rest of the world. One possible explanation is that important cultural traits were transmitted from south to east at this time. Here we identify a mitochondrial signal of such a dispersal soon after ~70 ka the only time in the last 200,000 years that humid climate conditions encompassed southern and tropical Africa. This dispersal immediately preceded the out-of-Africa expansions, potentially providing the trigger for these expansions by transmitting significant cultural elements from the southern African refuge.

URL: https://www.nature.com/articles/s41598-019-41176-3 (no paywall)

Chad Rohlfsen
03-30-2019, 07:33 PM
Problem is, another species was living there...

29580

NetNomad
03-30-2019, 07:45 PM
Problem is, another species was living there...

29580

Hmm, interesting..

He seems to be talking about this: https://en.wikipedia.org/wiki/Homo_naledi

Megalophias
03-30-2019, 08:05 PM
According to that Homo naledi is dated to around 250 000 years ago. And why couldn't they have existed at the same time as Homo sapiens anyway? It's just assumed we would competitively exclude any other hominin, even if physically very different?

NetNomad
03-31-2019, 08:48 AM
If their L0 originated in Southern Africa theory is true, then A1b1 (L419/PF712) may have originated in Southern Africa as well, possibly even A1b1b (A-M32, the ancestor of A1b1b2b/A-M13).

epoch
03-31-2019, 10:01 AM
According to that Homo naledi is dated to around 250 000 years ago. And why couldn't they have existed at the same time as Homo sapiens anyway? It's just assumed we would competitively exclude any other hominin, even if physically very different?

Well, it would be the exception. Evereywhere else AMH replaced the other hominims, absorbing a part of it. Also, West-Africans, Bushmen and Pygmee's have traces of archaic admixture which narrows it down to East and North Africa. The oldest AMH to date is Jebel Irhoud.

But this all is absolutely no conclusive evidence.

Megalophias
03-31-2019, 04:08 PM
Well, we conquered the world 50 000 years ago, but before that clearly we couldn't overrun all other humans.

Anyway, this paper is suggesting that cultural developments in South Africa about 100-70 000 years ago were transmitted to East Africa about 70 000 years ago. Is John Hawks saying that Homo naledi is now dated that late - Homo sapiens hadn't arrived yet? I cannot find anything that suggests this.

epoch
03-31-2019, 07:13 PM
Well, we conquered the world 50 000 years ago, but before that clearly we couldn't overrun all other humans.

True, although Kuhlwilm (https://www.nature.com/articles/nature16544) et al showed that there was a semi-successful dispatch earlier.


Anyway, this paper is suggesting that cultural developments in South Africa about 100-70 000 years ago were transmitted to East Africa about 70 000 years ago. Is John Hawks saying that Homo naledi is now dated that late - Homo sapiens hadn't arrived yet? I cannot find anything that suggests this.

True again. John Hawks is quick to respond. Then again, it's twitter and that is exactly the medium for such immediate yet unredacted responses.

Another thing is this: The paper suggests a small migration..


The number of migrants from the south was probably not very large, as reflected in the present-day frequencies of L0 in eastern Africa of 5–15% on average

..yet suggests it had a deep impact:


It is therefore tempting to speculate that the migrants at 70–60 ka might have transmitted innovations developed in the southern refuge, such as microlithic technology or even novel symbolic activities, to eastern Africa

I dunno.. Symbolism seems like a hereditary rather than an acquired treat, wouldn't you say? Then I think that the evidence, meager as it may be, that there was symbolic behaviour in the Skhul and Qafzeh sites is basically evidence that we simply haven't stumbled upon the Middle-Eastern equivalent of Blombos cave yet.


These are not completely unique to this region or even to Homo sapiens: beads similar to those seen in southern Africa have been found in Morocco at ~82 ka and even earlier in the Levantine coastal sites of Skhul and Qafzeh, and there are even examples amongst European Neanderthals.

Megalophias
03-31-2019, 07:20 PM
Yeah, the paper's claim doesn't seem very convincing to me either, I just don't get what Homo naledi has to do with it.

GailT
04-01-2019, 10:16 PM
It is an interesting paper - it seems very speculative, but plausible speculation. We really need more ancient DNA from Africa at much older dates to test this. One interesting speculation in the paper:


In genetic terms, the earliest out-of Africa populations might even have carried a low level of southern African ancestry, but the out-of-Africa bottleneck was very drastic, with the maternal lineage of all humans outside Africa eventually deriving from a single (and likely random) eastern African sequence, the root of haplogroup L3, and any hypothetical genome-wide South African ancestry was diluted through recombination.

There is a new L0a subclade, that I'm calling L0a5, that is not yet in Phylotree and that has only been found in Armenia L0a5 has an estimated age of about 50,000 years (with large uncertainty in that date because of the small number of samples). With only a few samples from Armenia that share a common maternal ancestor a few thousand years ago, it is not possible to estimate when L0a5 exited Africa, it could be at any time between about 50,000 to 2000 years ago. The fact that it has not yet been found in Africa might indicate an earlier rather than a later exit. I mention this because it is consistent with the speculation that the OoA migration around 70 to 60 ka might have include haplogroups other than L3.

palamede
04-03-2019, 09:29 AM
A dispersal of Homo sapiens from southern to eastern Africa immediately preceded the out-of-Africa migration

Abstract
Africa was the birth-place of Homo sapiens and has the earliest evidence for symbolic behaviour and complex technologies. The best-attested early flowering of these distinctive features was in a glacial refuge zone on the southern coast 100–70 ka, with fewer indications in eastern Africa until after 70 ka. Yet it was eastern Africa, not the south, that witnessed the first major demographic expansion, ~70–60 ka, which led to the peopling of the rest of the world. One possible explanation is that important cultural traits were transmitted from south to east at this time. Here we identify a mitochondrial signal of such a dispersal soon after ~70 ka – the only time in the last 200,000 years that humid climate conditions encompassed southern and tropical Africa. This dispersal immediately preceded the out-of-Africa expansions, potentially providing the trigger for these expansions by transmitting significant cultural elements from the southern African refuge.

URL: https://www.nature.com/articles/s41598-019-41176-3 (no paywall)

Until a long time we know there had been a beautiful very old stone technology in South Africa since 90,000BP , but what is the influence about the first eurasian stones technologies of the AMH, if any ?

But I think the paper understimates the dates compared to tmrca of haplogroups given by Yfull, tmrca already often considered as underestimated
https://www.yfull.com/tree/A0-T/

A0-T formed 235900- 161300 I suppose 235900 is their mean estimated bifurcation date of A0-T and A00
-- A1 tmrca 133400
---- A1b tmrca 130700
------ A1b1 tmrca 121600
-------- BT tmrca 88000
---------- B tmrca 83600
----------- CT tmrca 68500
------------- DE tmrca 65200
------------- CF tmrca 65900

The politically correct consensus cannot reject the numerous evidences for an important "out of Africa" during the very favorable interglacial Eemian 130,000-120,000 when a lot of African zoological and botanical species migrated to Asia and they have survived until now. After the phase 5e Eemian the most favorable, it remains good conditions in Yemen, Asir, Dhofar, Oman, Gulf oasies and elsewhere more northern to survive , even, if Neanderthal was present in the north of Middle East during the first pleniglacial, maybe the time of a first introgression .
The politically correct consensus (which was always partisan of the lowest possible datation : 40,000BP 20 years ago before the datationd of the Australian/New Guinea settlement ) claimed there was a dead end for this first vague and now they placed the successfull "Out of Africa" during the first pleniglacial 75,000-60,000 when the climatic conditions were the less favorable for a migration thru Saharian, Arabian and Iranian deserts and altogether, only some millenia were enough to reach South China, Indochina, Sunda and Sahul.