Figure 7. Ancestral state reconstruction of the patella in Eutheria.

The main tree shows a parsimony reconstruction using unordered character states, where branch colour indicates the reconstructed state. Our results suggest that the ossified patella evolved only once within Eutheria and (as far as is currently known) has only been lost by the bat genus Pteropus (not counting groups which have lost hindlimbs, e.g. Trichechus manatus/crown Sirenia, Tursiops truncatus/crown Cetacea).