Caucasian origin
Main article: Caucasian origin of the Azerbaijanis
According to Encyclopædia Britannica about Azeris in the Republic of Azerbaijan:
“ The Azerbaijani are of mixed ethnic origin, the oldest element deriving from the indigenous population of eastern Transcaucasia and possibly from the Medians of northern Persia.[92] ”
The Caucasian origin mostly applies to the Azeris of the Caucasus, most of whom are now inhabitants of the Republic of Azerbaijan. There is evidence that, despite repeated invasions and migrations, aboriginal Caucasians may have been culturally assimilated, first by Iranians and later by the Oghuz. Considerable information has been learned about the Caucasian Albanians including their language, history, early conversion to Christianity, and close ties to the Armenians. Many academics believe that the Udi language, still spoken in Azerbaijan, is a remnant of the Albanians' language.[93][94]
This Caucasian influence extended further south into Iranian Azerbaijan. During the 1st millennium BCE, another Caucasian people, the Mannaeans (Mannai) populated much of Iranian Azerbaijan. Weakened by conflicts with the Assyrians, the Mannaeans are believed to have been conquered and assimilated by the Medes by 590 BCE.[95]
Genetics
Some new genetic studies suggest that recent erosion of human population structure might not be as important as previously thought, and overall genetic structure of human populations may not change with the immigration events but in the Azerbaijani case; some Azerbaijanis of Azerbaijan republic genetically resemble other Caucasian people like Kurds and Armenians[96] and people in the Azerbaijan region of Iran to other Iranians.[97]
According to a study of Eurasia's population by the American Society of Human Genetics, the different Iranian populations show a striking degree of homogeneity and nonsignificant FST values among themselves.[98] It seems that the people are largely Iranian settlers both before and after Islam.
2010 genetic study of Andonian et al shows Turkification of this region was predominantly by the process of elite dominance, i.e. by the limited number of invaders who left only weak patrilineal genetic trace in modern populations of the region and not mass migration.[99]
Studies conducted at Cambridge and Stanford Universities
A recent study of the genetic landscape of Iran was completed by a team of Cambridge geneticists led by Dr. Maziar Ashrafian Bonab (an Iranian Azerbaijani).[100] Bonab remarked that his group had done extensive DNA testing on different language groups, including Indo-European and non Indo-European speakers, in Iran.[101] The study found that the Azerbaijanis of Iran do not have a similar FSt and other genetic markers found in Anatolian and European Turks. However, the genetic Fst and other genetic traits like MRca and mtDNA of Iranian Azeris were identical to Persians in Iran.
In 2006 M. Regueiro and A.M. Cadenas of Stanford University show that the population of central Iran (Isfahan) group to Caucasian Azeri people more than population of Turkey in terms of haplogroup distributions and genetic homogeneity.[102]
Studies conducted in the Caucasus
A study in 2011 showed that the Iranian Azaris have much weaker genetic affinity with the populations from Central Asia and the Caucasus than with their immediate geographic neighbors in Iran.[103]
A 2003 study found that: "Y-chromosome haplogroups indicate that Indo-European-speaking Armenians and Turkic-speaking Azerbaijanians (of the Republic of Azerbaijan) are genetically more closely related to their geographic neighbors in the Caucasus than to their linguistic neighbors elsewhere."[104] The authors of this study suggest that this indicates a language replacement of indigenous Caucasian peoples. There is evidence of genetic admixture derived from Central Asians (specifically Haplogroup H12), notably the Turkmen, that is much higher than that of their neighbors, the Georgians and Armenians.[105] MtDNA analysis indicates that the main relationship with Iranians is through a larger West Eurasian group that is secondary to that of the Caucasus, according to a study that did not include Azerbaijanis, but Georgians who have clustered with Azerbaijanis in other studies.[106] The conclusion from the testing shows that the Caucasian Azeris are a mixed population with relationships, in order of greatest similarity, with the Caucasus, Iranians and Near Easterners, Europeans, and Turkmen. Other genetic analysis of mtDNA and Y-chromosomes indicates that Caucasian populations are genetically intermediate between Europeans and Near Easterners, but that they are more closely related to Near Easterners overall.[104] Another study, conducted in 2003 by the Russian Journal of Genetics, links Iranians in Azerbaijan (the Talysh and Tats) with Azerbaijanis of the Republic:
“ the genetic structure of the populations examined with the other Iranian-speaking populations (Persians and Kurds from Iran, Ossetins, and Tajiks) and Azerbaijanis showed that Iranian-speaking populations from Azerbaijan were closer to Azerbaijanis than to Iranian-speaking populations inhabiting other world regions.[107] ”
A 2011 study at Yerevan State University and Tehran University of Medical Sciences shows Azeris have much weaker genetic affinity with the populations from Central Asia and the Caucasus than with their immediate geographic neighbours. Relying on these outcomes one can suggest that language change with regard to Azeris occurred through elite dominance mechanism rather than demographic diffusion model.[103]