Recent Genetic Evidence Helps Synthesize Two Hypotheses to Solve Indo-European Homeland Puzzle

Search for the homeland of the original Indo-European (IE) speakers has been a quest for more than two centuries. Though many hypotheses have been put forward over the years, none of them have been completely consistent with all evidence available from linguistics, archaeology, and genetic research. While there are two hypotheses that have garnered significant support, both have inconsistencies with what is known. In this article, we collate the evidence now available from genetic research about the ancestry of current and past attested IE speaking population and show that the Neolithic Iranian farmers are the most likely candidate of being the original IE speakers as they are the only population who have contributed their genes to all attested IE speakers. Migration path as identified by genetic research clearly shows that both in Europe and in south Asia the IE speaking population is a product of three-way admixture. In south Asia, the admixture happened in Neolithic period between local population and Iranian farmers and later between the resultant population and Steppe pastoralists who in turn got half their ancestry from Iranian farmers. In Europe similar admixture happened first between local population and Anatolian farmers who in turn had part of their ancestry from Iranian farmers and second with Steppe pastoralists. We assert that since Iranian farmers were the original IE speaker both Anatolian farmers and Steppe pastoralists were IE speaker implying that both in Europe and in south Asia there were admixture of two branches of IE speakers. Therefore, we name our hypothesis as "Admixture hypothesis". We also show that our hypothesis is consistent with the available data from Archaeology and Linguistics.