Fig. 4

Posterior traces of ancestral locations and posterior migrations for four Ebola virus lineages from genomes (top) and GP sequences (bottom). The inferred ancestral branch location is logged at time points along the path from selected tips to the root of the tree across the posterior distribution of trees. The smoothed trajectories are an indication of where and when a lineage that gave rise to a particular tip is inferred to have existed. Maps on the right show migration events that are inferred to have taken place coloured by their posterior probability with migrations with <0.05 posterior support are shown as dotted white lines. All lineages share a common ancestor in Guéckédou prefecture of Guinea (white outline in the map) where the original zoonotic transmission event occurred near the Guinean border with Sierra Leone and Liberia. Some lineages are also descended from an early spillover event into Sierra Leone