The future of the Eurasian past: highlighting plotholes and pillars of human population movements in the Late Pleistocene

The major genetic divergences among non-Africans took place within a relatively short period of time, between 50 and 40 thousand years ago. These events shaped human diversity worldwide and set the basis for our current understanding of demographic history, patterns of adaptation and genetic burden across human populations. While the global picture appears already set, with the main human expansion Out of Africa inferred to have occurred between 60 and 70 thousand years ago and the main separation between contemporary East and West Eurasian to have taken place at around 40 thousand years ago, several finer details remain unresolved, including the whereabouts of such expansions and the dynamics of their interactions with archaic hominins and the interplay between environmental, cultural and demographic effectors. Here we review the major events that characterize human movements across and beyond Eurasia until the last glacial maximum and, at the end of each paragraph, spell out in italics the major questions that remain unsolved and that may provide major breakthroughs in the field in the upcoming years.