groups with more ANI relatedness into ones with less". "suggest that ancient male-mediated migratory events and settlement in various regional niches led to the present day scenario and peopling of India." Mahl (2021), in a study of the Brahmin ethnic group, identified the ancient male protagonists of the sampled population could be traced to twelve geographic locations, eleven of which were outside South Asia. Of the Y-DNA haplogroups identified, four were carried by ~83% of those sampled, and of these four, two were of Central Asian origin and one of the Fertile Crescent. All sampled groups were admixed with populations of South Asian origin. North-south cline According to there is "a general principal component cline stretching from Europe to south India". This northwest component is shared with populations from the Middle East, Europe and Central Asia, and is thought to represent at least one ancient influx of people from the northwest. According to Saraswathy et al. (2010), there is "a major genetic contribution from Eurasia to North Indian upper castes" and a "greater genetic inflow among North Indian caste populations than is observed among South Indian caste and tribal populations". According to and Saraswathy et al. (2010) certain sample populations of upper caste North Indians show a stronger affinity to Central Asian caucasians, whereas southern Indian Brahmins show a less stronger affinity. Scenarios While Reich notes that the onset of admixture coincides with the arrival of Indo-European language, according to Metspalu (2011), the commonalities of the ANI with European genes cannot be explained by the influx of Indo-Aryans at ca. 3,500 BP alone. They state that the split of ASI and ANI predates the Indo-Aryan migration, both of these ancestry components being older than 3,500 BP." Moorjani (2013) states that "We have further shown that groups with unmixed ANI and ASI ancestry were plausibly living in India until this time." Moorjani (2013) describes three scenarios regarding the bringing together of the two groups: "migrations that occurred prior to the development of agriculture [8,000–9,000 years before present (BP)]. Evidence for this comes from mitochondrial DNA studies, which have shown that the mitochondrial haplogroups (hg U2, U7, and W) that are most closely shared between Indians and West Eurasians diverged about 30,000–40,000 years BP." "Western Asian peoples migrated to India along with the spread of agriculture [...] Any such agriculture related migrations would probably have begun at least 8,000–9,000 years BP (based