Fig. 3

Ancestral state reconstruction for simple and compound (unifoliolate, note the articulation at the base of the leaflet marked by a black arrow, trifoliolate, and multifoliolate) leaves under a symmetrical rates model, carried out on a chronogram resulting from a strict clock model implementing a fossil-based constraint for 183 Crotalaria species, 33 species of other Crotalarieae, and 23 species of the remaining genistoids. Pie charts indicate ancestral state probabilities, and node bars 95% posterior probability intervals for nodes ≥0.96 posterior probability. The geological time scale is in million years and follows Cohen et al. [5]. The fossil seedpod most closely resembles the genera Bowdichia and Diplotropis [19]. Photo: P. S. Herendeen. Additional file 5: Figure S5 shows the leaf states also coded for the outgroups