March 30, 2015

Ice age Europeans on the brink of extinction

Ice-age Europeans roamed in small bands of fewer than 30, on brink of extinction (Horizon magazine)
In some cases, small bands of potentially as few as 20 to 30 people could have been moving over very large areas, over the whole of Europe as a single territory, according to Professor Ron Pinhasi, principal investigator on the EU-funded ADNABIOARC project.

This demographic model is based on new evidence that suggests populations were much smaller than is generally thought to be a stable size for healthy reproduction, usually around 500 people. Such small groupings may have led to reduced fitness and even extinctions.

‘As an archaeologist and anthropologist, I was quite shocked to see how limited, how small the population numbers were. You know, shockingly small,’ said Prof. Pinhasi, based at University College Dublin, Ireland.

...

Prof. Pinhasi’s team has found that the genomes sequenced from hunter-gatherers from Hungary and Switzerland between 14 000 to 7 500 years ago are very close to specimens from Denmark or Sweden from the same period.

These findings suggest that genetic diversity between inhabitants of most of western and central Europe after the ice age was very limited, indicating a major demographic bottleneck triggered by human isolation and extinction during the ice age.

‘We’re starting to be able to reconstruct the actual dynamics of migrations and colonisation of the continent by modern humans and that’s never been done before the genomic era,’ explained Prof. Pinhasi.

He believes that early humans crossed the continent in small groups that were cut off while the ice was at its peak, then successively dispersed and regrouped over thousands of years, with dwindling northern populations invigorated by humans arriving from the south, where the climate was better.

‘You see a real reduction in population numbers and diversity, so you see the few lineages that probably split or separated before the ice age, and then stayed isolated during the ice age,’ he said. ‘Some time after the ice age, they kind of re-emerge, or disperse, and get together, as we see new contributions to European lineages from Asia and in particular the Near East.’
The last couple of statements are interesting because they hint at post-glacial recolonization of Europe after the Ice Age. So far, we are in the dark about what happened in Europe between the time of Kostenki and 8kya. Hopefully another interesting study is on its way to throw some light into the lattter part of this time interval.


11 comments:

Gioiello said...

This coud be another demonstration that R-M269 wintered in Western Europe with its bottleneck of more than 6000 years, and the same some lines of hg. I: see the YFull tree and also the "smal tree" on "R1b1a2 (P312- U106-) DNA Project". The same E-V13 and so on...

arch said...

which is all kind of pointless, because the mega-majority of modern european descended peoples outside of Finland or the Baltics do not have any meaningful shred of ancestral descent from this pre-Indo population.

pretending that there is large scale or even meaningful scale genetic continuity into modern europeans from the ice age isnt based in any reality

DARK MATTER AND THE EXPANSION OF OUR UNIVERSE said...

Where did you get the genetic material to determine the facts of this article.

Gioiello said...

Both R1a-M198 (formed 14300 ybp, TMRCA 8400 ybp), R1b1-V88 (formed 16700 ybp, TMRCA 7300 ybp) and R1b-M269 (formed 13100 ybp, TMRCA 7000 ybp) emerged after a bottleneck of 6000 years. As I have written about the Haak's paper on Samara, I think R1a in Northern European hunter-gatherers and R1b in the Southern Europeans ones.

eurologist said...

"He believes that early humans crossed the continent in small groups that were cut off while the ice was at its peak, then successively dispersed and regrouped over thousands of years, with dwindling northern populations invigorated by humans arriving from the south, where the climate was better."

I mean, that's not exactly news, here. Sometimes it's worthwhile to consider archaeological evidence, as well...

...which also tells us that the northern (and even central) populations were not "dwindling," but rather non-existent during LGM.

Also note that the graphic in the article states: "First homo sapiens 'out of Africa' 125 000 years ago"! :thumbup:

Anonymous said...

there were U5b1 who were already ~13ka on the Rhine at Oberkassel attested . Loschbour too was U5b1 which back then perhaps belonged to the same group at Rhine valley.
About Y not sure. I2 are expected.
I just don't think that I and C were in south Iberia. that's why I think E1b1b or non-m269 R1b were possibly there and in Switzerland north the alps.

Unknown said...

I dont think we have anything like the amount of data we would need to make such sweeping statements. The is pop-science pulp and insubstantial.

Grey said...

so they didn't go extinct then

and the survivors weren't completely wiped out by near eastern farmers

so it only needs some of them to have survived the Indo-Europeans and they made it.

batman said...

@Grey

No they didn't.

In fact they saurvived both the LGM as well as rhe Older and Yomnger Dryas - contrary to the arctic lions, tigers, rhinos and eleafants (mommoths). The last mammoths and giant deers made it through both of the first cold-periods, but not thoough the last, shortest but worst one.

As the Laacher See volcano kick-started the Younger Dryas, 12.900 yrs BP, the last populations of mammoths died out. The very lasts ones known lived some 13.000 yrs ago - in England, Denmark, Skaney and Estonia.

Thus e do know where the last climate refugia was - which is now confirmed as they discover that spruce and pine, oxen and cows, horses and beavers have survived the last and worst cold-periods in ice-free pockets of coastal Scandinavia.

Consequently we will have to re-define the extent of the Scandianvian Ice-sheet - and consequently reasess the location of the possible refugias of the Eurasian paleolithic.

Today we have ONE time-line that may explain the continuity - from paleolithic to mesolithic - as stated by this study. TThuis line starts with the palaolithic cultures of the Aurignac/Mousterien/Gravettien - through the periods of Solutrean that beacme 'Magdalenien' during the LGM, before it manifests as "the Hamburg-culture" - as in Ahrensburg and Bromme - before the last and terminal cold-dip.

Obviously the humans that managed to survive LGM and OD - at the danish islands of Older and Younger Dryas - was the very first to start re-producing and populating northern Eurasia after ice-time. Thus wwe have location for the'cradle' of the poast-cro-nagnons, also called 'caucasians'.

Since they had survived ice-time in the north they were already ell-equiooed, physically as well as culturally, to live and prosper in the climates. Thus we may understand how they could spread all over northern Eurasia as soon as the warmer Holocene-period got started, between 12.000 and 11.700 years BP.

On the female side there was obviously some hg U involved, probably also V and T. On the male side there were obviously som hg F involved, from which it was possible to produce (new) lines of GHIJK, as the new populations took shape. Thus we may have to look for a 'most recent ancestor' among the refugiants of the Bromme-Lyngby-culture, known to have survived the last and terminal phase of ice-time, even if by only a few...

http://en.wikipedia.org/wiki/Bromme_culture



batman said...

Redrawing the map of ice-age Scandinavia:

http://sciencenordic.com/trees-survived-ice-age-scandinavia

Refugiants from the northern shores of the Atlantic facade:

http://sciencenordic.com/scandinavians-are-earliest-europeans

Mark Moore (Moderator) said...

Apparently mountain gorillas have been dealing with a population size with a median size of a few hundred for thousands of years. Maybe these folks did the same. http://www.sciencedaily.com/releases/2015/04/150409143031.htm