Reconstruction of divergence dates and ancestral distributions of MOTUs. (a) Phylogenetic relationships among 49 GMYC-species and definition of 27 MOTUs. The vertical line indicates the threshold where the speciation processes are replaced by coalescence. Black circles indicate strong support (>95%) for either speciation (left of the threshold) or intraspecific coalescence (right of the threshold). White circles indicate weak support (<95%) for these processes. The dating of divergences within Nannomys was assessed by BEAST using the previously estimated divergence times (see Additional file 2) as priors for calibration of relaxed molecular clock. (b) Reconstruction of ancestral distribution areas (blue – mountains in Eastern Africa, green – tropical forests of central and western Africa; red – open savannah-like habitats surrounding forests and mountains in sub-Saharan Africa. The different colours on pie charts indicate the probability of a particular state of the trait for each node. The analysis of ancestral traits was performed in BEAST (see text for more details).