Fig. 4.

Genomic scenario of the human dynamics in north Sahul during the Upper Pleistocene. Light blue arrows represent the settlement of north Sahul following a scenario with one migration to Sahul (model A). The dark blue arrows represent the settlement of north Sahul following a scenario with two migrations to Sahul (model B). The dotted dark blue arrow represents a gene flow following a scenario with two migrations to Sahul (model B). Yellow arrows represent the settlement of New Guinea. The dotted orange arrows represent gene flows after the initial settlement of Sahul. The black dots represent approximate locations of archaeological sites older than 40 ka (O’Connor 2007; Summerhayes et al. 2017). The dashed black lines represent ecological lines in Wallacea. The dark gray areas represent current land area, with light gray areas representing estimated land area around 50,000 years ago based on paleogeological reconstructions (Coller 2009).