Fig. 1.

Schematic representation of the spatially structured model representing the history of Neanderthals and anatomically modern humans. We start with a connected string of demes representing the common ancestor (in light blue), spanning Africa and Eurasia (A). Following the split (B), the northern part of the range becomes Neanderthals (purple), and the African part of the range eventually becomes modern humans (in orange). From this African range, modern humans later expand to colonize Eurasia (in red) (C). This figure only provides the logic of the model; for details, including the actual number of demes, see Materials and Methods.