The populations that eventually populated Australia and New Guinea were part of the same broad dispersal.

The populations that later moved through northeastern Asia toward Beringia would have shared some ancestry with these early southern-route dispersers, because the early human populations of Asia were not completely separate from each other — they interacted and mixed to varying degrees.

The specific affinity of the Population Y signal to Andamanese, Australian, and New Guinean populations — rather than to East Asian or South Asian populations more broadly — points to a specific ancestral component related to these early-dispersing southern-route populations, rather than a general affinity to Asian populations as a whole.

This specificity is one of the aspects of the Population Y signal that makes it scientifically interesting and that constrains the range of plausible explanations.