Fig. 1

The general model and the constrained models. Diagrammatic representations of the general model with no constrained transition rates; an example of a constrained zero model (n3 model) with some transition rates (in this case rate 3, from cryptic solitary to cryptic group) constrained to 0, and examples of two types of constrained equal models (eq47 model and eq57 model) with two of the transition rates (shown as blue dashed arrows) equal. Figure symbols: cryptic (grey), aposematic (red); solitary-living (one triangle), group-living (four triangles)