Thanks Angela, very interesting thread!
Those early farmers in southern Sweden ca. 4000 BC were in my opinion people of I1 haplogroup.
Igmayka from Anthrogenica wrote:
YFull estimates that I1 diverged from I2 27,500 years ago, but
began to expand only 4700 years ago. This means that exactly one (pre-)I1 lineage survived across the intervening 22,800 years. I don't see how we will ever know where that one lineage sojourned across so many millennia. If, just for example, we find a 20,000-year-old pre-I1 in Spain, and a 10,000-year-old pre-I1 in the Caucasus, we cannot assume that the one lineage that survived until today ever lived in either of those places. Who knows how many pre-I1 lineages went extinct, and where they might have lived and died?
We have a Transdanubian LBK sample of I1 named BAB5 from Balatonszemes-Bagódomb in Hungary. In my opinion that specific (pre-)I1 was originally a European hunter-gatherer lineage which was assimilated by LBK farmers. Then from LBK culture it got to Lengyel culture, and from Lengyel to TRB culture (Funnelbeaker). It experienced a founder effect, perhaps in the northern group of Funnelbeaker. This is why we have such a high frequency of I1 in Scandinavia. This lineage, among others, could also be responsible for spreading the lactase persistence mutation, as it turns out that the northern group of TRB farmers in southern Sweden were highly skilled in dairy farming, in cattle breeding and calving ca. 6000 ybp:
http://www.archaeology.org/news/3613-150817-neolithic-scandinavian-farmers-were-sophisticated
http://sciencenordic.com/first-scandinavian-farmers-were-far-more-advanced-we-thought
ALMHOV, SWEDEN—Researchers studying cow teeth from southern Sweden
dating to around 4000 B.C. have found evidence that early farmers there knew more about livestock husbandry than previously thought. By analyzing the oxygen isotopes in the teeth, the team found that cows were born over the course of a year, not just one season, indicating that the Neolithic farmers could control when calves were born. “It’s very interesting that the farmers of the period were able to manipulate the calving seasons, so all the calves did not come in the spring,” Durham University's Kurt Gron told
ScienceNordic. “This is very hard to do, and would not have taken place if the farmers had not intended to do it.”
By controlling the calving season, the farmers had access to milk year round, which suggests to some archaeologists that the farmers were so sophisticated that they were probably immigrants from Central Europe where such livestock practices were already established. To read about the technology used by people around this time in Europe, go to
"Neolithic Toolkit."
The Transdanubian LBK farmer with I1 lived around 7000-7500 years ago. The oldest samples of I1 from southern Sweden are from 3500 - 3100 years ago. LBK was a Neolithic Non-IE culture. It participated in formation of Lengyel, and northern groups of Lengyel then participated in formation of TRB - which was a farming (Neolithic) culture, but with evidence of assimilation of Mesolithic hunters*. So either that particular lineage of I1 got to TRB from LBK via Lengyel (as the oldest sample of I1 is from Transdanubian LBK), or was assimilated directly by TRB.
Now that they have found evidence of diary farming in southern Sweden from 4000 BC, I'm fairly sure that those were most certainly I1 haplogroup farmers of the northern group of TRB culture.
*Citation:
"(...) The Funnelbeaker culture, short TRB (...) was an archaeological culture in north-central Europe.
It developed as a technological merger of local neolithic and mesolithic [hunter] techno-complexes between the lower Elbe and middle Vistula rivers, introducing farming and husbandry as a major source of food to the pottery-using hunter-gatherers north of this line. (...)"
In terms of mtDNA, TRB farmers were a blend of Near Eastern and European-Mesolithic lineages.
Read also about very considerable Non-Indo-European substrate assimilated into Proto-Germanic:
https://en.wikipedia.org/wiki/Germanic_substrate_hypothesis#Non-Indo-European_influence
The non-Indo-European substrate hypothesis attempts to explain the anomalous features of proto-Germanic as a result of creolization between an Indo-European and a non-Indo-European language. Germanicist John A. Hawkins sets forth the arguments for a Germanic substrate. Hawkins argues that the proto-Germans encountered a non-Indo-European speaking people and borrowed many features from their language. He hypothesizes that the first sound shift of Grimm's Law was the result of non-native speakers attempting to pronounce Indo-European sounds, and that they resorted to the closest sounds in their own language in their attempt to pronounce them.
At least 30% of Proto-Germanic vocabulary was of Non-Indo-European origin.
Most likely that came from TRB farmers, since now we know that Battle Axe* was an IE culture.
*Battle Axe = another name for Corded Ware, especially its Scandinavian branch.
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Northern range of farmers ca. 4500 BC (6500 years ago) and first farmers in Sweden - 4000 BC:
(implying that migrating farmers pushed into Scandinavia during those 500 years in-between):
Map based on these sources:
"Demic and cultural diffusion propagated the Neolithic transition across different regions of Europe":
(in
Early Neolithic in Southern Europe diffusion of farming was almost fully demic,
later in Northern Europe it was more cultural):
http://rsif.royalsocietypublishing.org/content/12/106/20150166.figures-only
And this information provided by Angela:
http://www.archaeology.org/news/3613-150817-neolithic-scandinavian-farmers-were-sophisticated
http://sciencenordic.com/first-scandinavian-farmers-were-far-more-advanced-we-thought
As for Neolithization - just like the title of that paper linked above says, Neolithization was not only demic, but also a cultural process (i.e. assimilation of local hunters into farmer communities).
There are several theories as to how did farmers spread into Europe. One says that they originated in Anatolia (Asia Minor) and came into the Balkans and then onwards. Another theory says that they originated in the Levant and came through Cyprus, Crete and Greece. In fact both theories can be partially true as there could be more than just one wave of immigrations. Farmers from Mesopotamia, Caucasus and North Africa could also participate in some regions. It seems that most of immigrants were from Western and Northern Anatolia, though. The spread of farming was also due to local hunters gradually adopting farming from farmers. But that was especially in Late Neolithic times, when we observe an increase in fequency of indigenous hunter lineages - alongside immigrant lineages - in people from farming communities of Central and Northern Europe. In Early Neolithic times, when farming was spreading in Southern Europe, assimilation of local hunter-gatherers into farming communities was much more limited.
The spread of farmers was initially (Early Neolithic) very rapid - along rivers they were colonizing 3 km per year, IIRC. They slowed down as they went into colder or less fertile areas, and there more of local hunters could be assimilated. Already in Middle Neolithic and then in Late Neolithic samples we observe more of local, Mesolithic lineages in Neolithic communities (there is even an autosomally unmixed Mesolithic sample in a Neolithic cultural context - a "freshly" absorbed hunter).
But Scandinavians are still to a larger degree descended from those Anatolians, than Estonians, Finns, Lithuanians, or Latvians. Of all groups, Estonians have the most of European hunter ancestry, Sardinians have the most of ancestry from Near Eastern farmers.
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As for Bell Beaker influence in Scandinavia on pre-PGmc (early Proto-Germanic):
IMO speakers of pre-PGmc language evolved in Scandinavia, primarily from the mixture of three groups, which came to Scandinavia as distinct immigrant waves: 1) people of the northern group of TRB (Funnelbeaker) culture, who were Neolithic agriculturalists (Non-IE substrate); 2) people of Corded Ware culture, which was Indo-European; and 3) people of Bell Beaker culture, also Indo-European.
Phonetically and grammatically Proto-Germanic (PGmc) language was most closely related to Proto-Balto-Slavic language, leading to the conclusion that the main carriers of pre-PGmc were probably Corded Ware people, and that Proto-Germanic evolved from a common ancestral Balto-Slavo-Germanic language (this is currently the mainstream hypothesis, AFAIK).
However - lexically PGmc was most closely related to both Proto-Italo-Celtic and Proto-Balto-Slavic, but similarities with Balto-Slavic are considered to be cognates (i.e. inherited from an earlier common origin), while similarities with Proto-It-CL are considered to be loanwords, albeit mostly archaic ones (probably from times of pre-Proto-Italo-Celtic phase, so those loanwords were inherited early on).
About 30% or more of PGmc vocabulary is actually Non-IE, picked up from those TRB farmers.
In archaeological terms there was considerable influence of Hallstatt culture (Celts) on Nordic Bronze Age, which led to emergence of Jastorf culture. And later there was also considerable influence of La Tene culture (Celts) on Jastorf culture, which lead to latenization of the latter (here Latenization = an archaeological term referring to the diffusion of the Celtic material La Tene culture).
These archaic loanwords from pre-Proto-It-CL could be from earlier times, from Beaker people.