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View Full Version : Ancestral mitochondrial N lineage from the Neolithic ‘green’ Sahara



NetNomad
03-06-2019, 04:00 PM
Abstract
Because Africa’s climate hampers DNA preservation, knowledge of its genetic variability is mainly restricted to modern samples, even though population genetics dynamics and back-migrations from Eurasia may have modified haplotype frequencies, masking ancient genetic scenarios. Thanks to improved methodologies, ancient genetic data for the African continent are now increasingly available, starting to fill in the gap. Here we present newly obtained mitochondrial genomes from two ~7000-year-old individuals from Takarkori rockshelter, Libya, representing the earliest and first genetic data for the Sahara region. These individuals carry a novel mutation motif linked to the haplogroup N root. Our result demonstrates the presence of an ancestral lineage of the N haplogroup in the Holocene “Green Sahara”, associated to a Middle Pastoral (Neolithic) context.

URL: https://www.nature.com/articles/s41598-019-39802-1 (no paywall)

NetNomad
03-06-2019, 04:21 PM
I hope that they eventually extract autosomal data from these ancient remains. I'd assume they are similar to the Taforalt Iberomaurusian population if I were to guess.

pgbk87
03-06-2019, 04:32 PM
Does this revive the argument for an (Supra-Saharan) African origin of mtDNA M & N?

NetNomad
03-06-2019, 04:35 PM
Does this revive the argument for an (Supra-Saharan) African origin of mtDNA M & N?

It helps that side of the argument, but then again skeptics will then argue that they are North Africans with back-migration ancestry.

It is an interesting find nevertheless.

pgbk87
03-06-2019, 05:09 PM
It helps that side of the argument, but then again skeptics will then argue that they are North Africans with back-migration ancestry.

It is an interesting find nevertheless.

Agreed. If they were only able to sequence autosomal DNA or mtDNA from more specimens, it would give better clarity on the matter.

Mansamusa
03-06-2019, 11:38 PM
Does this revive the argument for an (Supra-Saharan) African origin of mtDNA M & N?

It ought to, but most professional geneticist and amateur genetic bloggers will favor far-fetched and unproven Eurasian back-migration theories as an alternative explanation, as do the authors of the paper who nowhere even mention the possibility of an African origin in their rambling conclusion. Here they are:


The M and N haplogroups, which lie at the base of Eurasian mtDNA diversity, are today globally distributed outside Africa and are dated to around 50–65 ka, very close to the ancestral L3 clade. Their divergence from it is commonly considered to have occurred outside Africa or during the expansion. The Arabian Peninsula represents a possible area where this occurred and a cradle from which the new branches spread toward Eurasia and back to Africa,

Only in Africa will the discovery of an ancestry mitochondrial lineage be interpreted as evidence of origin from somewhere else. They even suggest that pastoralism in Africa, which is older than in the Middle East, was brought in by Eurasians:


It is known that livestock was introduced from Southwest Asia33 and early pastoralist connections between Northeast Africa and Arabia are indicated by a few sites along the Red Sea with sheep/goat dated to ~8.1–7.5 ka34,35,36. Thus, the spread of pastoralism from the Levant to Northeast Africa could probably represent the context for the introgression of the N haplogroup into the central Sahara, even if it is commonly associated with derivative lineages

The idiocy will never end!

Megalophias
03-07-2019, 12:11 AM
Less basal than Oase-1 in Europe. Certainly, it could be a remnant from before Out of Africa, not much evidence either way.

One of the Dzudzuana samples was U6 and one is just said to be N. I wonder if that could be pre-N as well? U6 showed up after Oase-1 in Romania (35 000 years ago) too. And of course in North Africa. Probably coincidence though.

beyoku
03-07-2019, 05:31 PM
. They even suggest that pastoralism in Africa, which is older than in the Middle East,:


Source ?

Anyone have any hypothesis on autosomal affinity?

NetNomad
03-07-2019, 05:41 PM
Source ?

Anyone have any hypothesis on autosomal affinity?

Like those Taforalt samples, most likely. Perhaps with even more Natufian affinity because they are more Eastern located.

Megalophias
03-07-2019, 07:45 PM
The paper says "It is worth noting, however, that when geometric morphometric analysis of the skull of TK RS H1 is compared with a large published dataset it shows closer affinities with sub-Saharan contexts, such as Gobero in Niger whose occupation is dated from ~9.6–4.8 ka", citing a study that I can't get access to. Not clear if means Kiffian or Tenerean or both. The oldest Tenerean pastoralists would be contemporary I think.

Going out on a limb: a line from Sardinia through Tunisia to Lake Chad passes through the highlands of the Central Sahara. Roy King has suggested before that R1b-V88 in Africa could be related to the spread of pressure-flaked blades and trapezoidal arrowheads across the Mediterranean - the Castelnovian culture of southwestern Europe and the Upper Capsian of Tunisia beginning ~7000-6500 BC - possibly with ultimate origins in Ukraine, where as we now know there was Mesolithic R1b-V88. Pastoralists apparently from the southern Sahara settled around Lake Chad ~1800 BC (Gajiganna culture). Kind of far-fetched but could be a link in a chain from southeastern Europe via the Capsian Neolithic to Central Africa. There's a subclade of A-M13 that's found in Sardinia as well: A-PH804, with downstream members in North and Central Africa - it could have gone north with Early Holocene foragers, then come back south with herders, some men crossing the opposite direction to R1b-V88.

On the other hand since they have an extinct mt haplogroup they might just not have left any significant number of descendants.

Mansamusa
03-08-2019, 03:57 PM
Source ?

Anyone have any hypothesis on autosomal affinity?

Nabta Playa and Its Role in Northeastern African Prehistory, Fred Wendorf
and Romuald Schild (https://ac.els-cdn.com/S0278416598903191/1-s2.0-S0278416598903191-main.pdf?_tid=84ecd74e-8987-4f16-9e05-f0835cfcfc2a&acdnat=1552060651_42970af6c60686cfa6dea129c0994fb2 ).

TuaMan
03-08-2019, 10:45 PM
There probably was not in fact an independent domestication of cattle in North Africa. Agro-pastoralism in Africa is an import from the Middle East.

https://link.springer.com/article/10.1007/s10963-017-9112-9


It is concluded that (a) Bos remains from the early Holocene at Nabta Playa—Bir Kiseiba were those of
hunted aurochs; (b) domesticated caprines were likely present in Northeast Africa
before domesticated cattle; and (c) the domesticated cattle spreading across
Northeast and northern Africa, including Nabta Playa—Bir Kiseiba, from the late
seventh millennium BC or early sixth millennium BC onwards were descendants of
Bos taurus domesticated in the Middle Euphrates area of the Middle East.

Mansamusa
03-09-2019, 04:34 AM
There probably was not in fact an independent domestication of cattle in North Africa. Agro-pastoralism in Africa is an import from the Middle East.

https://link.springer.com/article/10.1007/s10963-017-9112-9 I am familiar with the alternative explanations to Wendorf and Schild. They have been present from since the first day the seminal study by the two were published. This review is just an updated version of it. The review gives a comprehensive list of all teh evidence to support the domestication of cattle in Africa, and then just goes "Meh, it doesn't matter. They did not domesticate it!" Can we try to tell the difference between the opinions of researchers and the data they present? Wendorf and Schild remain resolute and stand behind their original conclusions, and they have published a number of updates.