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newtoboard
12-21-2013, 11:42 PM
Anyone have any idea?

GailT
12-22-2013, 12:09 AM
Just to make sure I understand your question - are you asking why a large variety of y-DNA A haplogroups did not expand into Eurasia? You can ask the same question about mtDNA: Why did only two subclades of L3 expand into Eurasia?

I think the Eurasian haplogroup distribution probably tells us something about the nature of the Out of Africa expansion. The lack of diversity might suggest that relatively small groups expanded into Arabia and/or the Near East. The apparent lack of repeated migrations of populations with a variety of haplotypes might be due in part to unfavorable climate, and to a highly successful initial expansion which increased in size rapidly. A large, successful Eurasian population could have been a barrier to subsequent migrations out of Africa. It seems like there must be studies that have analyzed this...?

newtoboard
12-22-2013, 12:25 AM
I was asking why there isn't any ydna A in some places?

I think a lack of diversity in the out of Africa explains it well. Is it also possible the out of Africa expansion started with CF? Or that downstream lineages were so successful that the frequency of A was reduced to pretty much 0?

lgmayka
12-22-2013, 01:42 AM
There is some A in Eurasia (http://www.familytreedna.com/public/Haplogroup_A/default.aspx?section=yresults).

newtoboard
12-22-2013, 02:15 AM
There is some A in Eurasia (http://www.familytreedna.com/public/Haplogroup_A/default.aspx?section=yresults).

Are we sure this Eurasian A isn't of recent African origin?

RCO
12-22-2013, 12:21 PM
A culturalist hypothesis:

The society of our “out of Africa” ancestors (I)
The migrant warriors that colonized the world
Eduardo Moreno

The “out of Africa” hypothesis proposes that a small group of Homo sapiens left Africa 80,000 years ago, spreading the mitochondrial haplotype L3 throughout the Earth.1–10 Little effort has been made to try to reconstruct the society and culture of the tribe that left Africa to populate the rest of the world.1 Here, I find that hunter-gatherers that belong to mitochondrial haplotypes L0, L1 and L2 do not have a culture of ritualized fights. In contrast to this, almost all L3 derived hunter-gatherers have a more belligerent culture that includes ritualized fights such as wrestling, stick fights or headhunting expeditions. This appears to be independent of their environment because ritualized fights occur in all climates, from the tropics to the arctic. There is also a correlation between mitochondrial haplotypes and warfare propensity or the use of murder and suicide to resolve conflicts. The data implicate that the original human population outside Africa is descended from only two closely related sub-branches that practiced ritual fighting and had a higher propensity towards warfare and the use of murder for conflict resolution. This warfare culture may have given the out of Africa migrants a competitive advantage to colonize the world. But it could also have crucially influenced the subsequent history of The Earth. In the future, it would be interesting to see how we could further reconstruct the society and culture of the “Out of Africa Tribe.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3104569/

RCO
12-22-2013, 12:28 PM
A sequence here:

The “Out of Africa Tribe” (II): Paleolithic warriors with big canoes and protective weapons
Eduardo Moreno*

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3656025/

rokousa
07-31-2014, 11:24 AM
Anyone have any idea?

what about incest?
imagine...5.000 men's share same y dna...5.000 women's share same mtdna...5.000 men's share same mtdna...no one had sex with A dna hg people or Lx women...
some Africans become angry, so OOA population is kicked out of Africa...
why?
since some people believe that humans are related to chimpanzee...and bible...Adam and Eve had 2 sons....Cain was the first human born and Abel was the first human to die...
so, Adam or/and his son Cain have childrens with Eve....

crossover
02-23-2016, 06:20 AM
Are we sure this Eurasian A isn't of recent African origin?

it probably is recent in the last few hundred years but since those people have been living in eurasia for a while, i'll still consider it an example of haplogroup a in eurasia

Ignis90
03-20-2016, 06:35 PM
Technically, there is A in Eurasia: all of them descend from a branch of A so all Eurasians are "A" (except if we find a Neanderthal lineage someday).

Tomenable
04-28-2016, 12:43 AM
Anyone have any idea?

Isn't there also a lack of B in Eurasia ???

A and B separated early on, and migrated to Southern Africa and Central Africa (respectively).

That's they generally didn't participated in OoA event.

=======================

Bonnie posted several maps of haplogroup B here:

http://www.anthrogenica.com/showthread.php?6155-Haplogroup-B-(and-subclades)-frequencies-by-populations-and-by-regions&p=132743&viewfull=1#post132743

As for A, there is some in Sardinia. Francalacci (2013) found 7 x A1b1b2b among 1204 Sardinians.

J Man
04-28-2016, 12:54 AM
Because A never had very large numbers of descendants and was rather confined to parts of Sub-Saharan Africa. Who knows why really?