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View Full Version : Neanderthals did coexist with Homo Sapiens in Europe



Jean M
08-20-2014, 06:39 PM
Here we go again. Another set of dates, reversing the conclusion of the last one!

New dates rewrite Neanderthal story

http://www.bbc.co.uk/news/science-environment-28693371


Modern humans and Neanderthals co-existed in Europe 10 times longer than previously thought, a study suggests. The most comprehensive dating of Neanderthal bones and tools ever carried out suggests that the two species lived side-by-side for up to 5,000 years. The new evidence suggests that the two groups may even have exchanged ideas and culture, say the researchers. The study has been published in the journal Nature.

dp
08-23-2014, 04:06 PM
Elsewhere I questioned what percentage of Neanderthal admixture was being reported in Geno 2 tests. I knew admixture was reported in Europe but I was a little surprised to find it in Africa too. Here's the article abstract from Plos One:
Citation: Sánchez-Quinto F, Botigué LR, Civit S, Arenas C, Ávila-Arcos MC, et al. (2012) North African Populations Carry the Signature of Admixture with Neandertals. PLoS ONE 7(10): e47765. doi:10.1371/journal.pone.0047765


One of the main findings derived from the analysis of the Neandertal genome was the evidence for admixture between Neandertals and non-African modern humans. An alternative scenario is that the ancestral population of non-Africans was closer to Neandertals than to Africans because of ancient population substructure. Thus, the study of North African populations is crucial for testing both hypotheses. We analyzed a total of 780,000 SNPs in 125 individuals representing seven different North African locations and searched for their ancestral/derived state in comparison to different human populations and Neandertals. We found that North African populations have a significant excess of derived alleles shared with Neandertals, when compared to sub-Saharan Africans. This excess is similar to that found in non-African humans, a fact that can be interpreted as a sign of Neandertal admixture. Furthermore, the Neandertal's genetic signal is higher in populations with a local, pre-Neolithic North African ancestry. Therefore, the detected ancient admixture is not due to recent Near Eastern or European migrations. Sub-Saharan populations are the only ones not affected by the admixture event with Neandertals.

I copied a graphic from the article which indicates that Tunisians have the greatest admixture.
2422
Figure 3. Neandertal genetic introgression in North African populations as a fraction of that found in Europeans.
Relative proportion of Neandertal ancestry for each population is presented as the dark blue section of the pies on a map of North Africa. Additionally, each population is also represented as a barplot of the different geographic genetic components; in red: North African, in blue: Sub-Saharan, in green: European, in yellow: Near East. Populations are shown as having Neandertal ancestry if the estimates are more than two standard errors from zero. Full name descriptions of these population labels are found in Table 2.

PS: IRT Tunisia see:Henn BM, Botigue´ LR, Gravel S, Wang W, Brisbin A, et al. (2012) Genomic Ancestry of North Africans Supports Back-to-Africa Migrations. PLoS Genet 8(1):
e1002397. doi:10.1371/journal.pgen.1002397

Here's a PCA figure from the Botigue paper. Notice the rightmost plot.
2424
-dp

J Man
08-24-2014, 01:01 AM
Elsewhere I questioned what percentage of Neanderthal admixture was being reported in Geno 2 tests. I knew admixture was reported in Europe but I was a little surprised to find it in Africa too. Here's the article abstract from Plos One:
Citation: Sánchez-Quinto F, Botigué LR, Civit S, Arenas C, Ávila-Arcos MC, et al. (2012) North African Populations Carry the Signature of Admixture with Neandertals. PLoS ONE 7(10): e47765. doi:10.1371/journal.pone.0047765


One of the main findings derived from the analysis of the Neandertal genome was the evidence for admixture between Neandertals and non-African modern humans. An alternative scenario is that the ancestral population of non-Africans was closer to Neandertals than to Africans because of ancient population substructure. Thus, the study of North African populations is crucial for testing both hypotheses. We analyzed a total of 780,000 SNPs in 125 individuals representing seven different North African locations and searched for their ancestral/derived state in comparison to different human populations and Neandertals. We found that North African populations have a significant excess of derived alleles shared with Neandertals, when compared to sub-Saharan Africans. This excess is similar to that found in non-African humans, a fact that can be interpreted as a sign of Neandertal admixture. Furthermore, the Neandertal's genetic signal is higher in populations with a local, pre-Neolithic North African ancestry. Therefore, the detected ancient admixture is not due to recent Near Eastern or European migrations. Sub-Saharan populations are the only ones not affected by the admixture event with Neandertals.

I copied a graphic from the article which indicates that Tunisians have the greatest admixture.
2422
Figure 3. Neandertal genetic introgression in North African populations as a fraction of that found in Europeans.
Relative proportion of Neandertal ancestry for each population is presented as the dark blue section of the pies on a map of North Africa. Additionally, each population is also represented as a barplot of the different geographic genetic components; in red: North African, in blue: Sub-Saharan, in green: European, in yellow: Near East. Populations are shown as having Neandertal ancestry if the estimates are more than two standard errors from zero. Full name descriptions of these population labels are found in Table 2.

PS: IRT Tunisia see:Henn BM, Botigue´ LR, Gravel S, Wang W, Brisbin A, et al. (2012) Genomic Ancestry of North Africans Supports Back-to-Africa Migrations. PLoS Genet 8(1):
e1002397. doi:10.1371/journal.pgen.1002397

Here's a PCA figure from the Botigue paper. Notice the rightmost plot.
2424
-dp

This does make sense as most North Africans are largely of West Eurasian origins genetically with a sizable SSA input.

dp
08-25-2014, 07:02 PM
This does make sense as most North Africans are largely of West Eurasian origins genetically with a sizable SSA input.
Last weekend I saw a TV show about the Vandals invading North Africa. I wonder if the Neanderthal DNA came via the Vandal invasion? Carthage became their capital, which is in present day Tunisia.
2437
http://en.wikipedia.org/wiki/Vandals
-dp
PS: of course it could go back to Phoenicians which led up to the Punic Wars.

J Man
08-25-2014, 09:45 PM
Last weekend I saw a TV show about the Vandals invading North Africa. I wonder if the Neanderthal DNA came via the Vandal invasion? Carthage became their capital, which is in present day Tunisia.
2437
http://en.wikipedia.org/wiki/Vandals
-dp
PS: of course it could go back to Phoenicians which led up to the Punic Wars.

I doubt that the Vandals contributed much in terms of the genetic ancestry of modern day North African peoples. Their Neanderthal ancestry comes mainly from their Near Eastern ancestors.