Are Chinese subsets of Southeast Asians?

That's probably the big takeaway of a new paper on the genetics of Asians, a set which includes South Asians, but in the new research mostly focuses on the people of East Asia. In a global context this work is important. The backstory is that there are disagreements about the exact process of the "Out of Africa" migration. Most researchers would agree that the vast majority, perhaps all, of the distinctive genetic content of the human species derives from a migration from the African continent between 50 and 100 thousand years ago (closer to the former date than the latter likely). Note that there were other human lineages outside of Africa, the Neandertals being the most prominent, but various "archaic" groups were extant in eastern Asia as well down to the arrival of modern African-derived human groups. This is part of the reason why H. floresiensis isn't that outlandish, a lineage of H. er ectus was extant in Southeast Asia until the ~50,000 years ago, with the arrival of moderns. Those are the agreements. The disagreement, in particular in regards to East Asia, is rather simple. Was there one, or two, waves from Africa, and did one, or both, settle East Asia? The two-wave model was promoted heavily in the early aughts by Spencer Wells. The whole argument is laid out in his book The Journey of Man: A Genetic Odyssey. The title hints to the fact that Wells and his collaborators primarily focused on paternal lineages, the Y chromosomes, in their reconstructions. Here's a screenshot from The Genographic Project which highlights the two-wave model: