The mammalian order Lagomorpha (hares, rabbits, pikas)

Detailed examination of the pedal morphology of extant and fossil lagomorphs revealed a unique channel (the “calcaneal ca− nal”) running diagonally through the lagomorph calcaneus. The ancientness, ubiquity, and appearance of the calcaneal ca− nal in all, including the earliest recognized lagomorph calcanea, and its absence from the pedes of other mammalian taxa, may indicate a long evolutionary separation of lagomorphs from other, previously suggested lagomorph relatives. While living members of this ubiquitous group are familiar to spe− cialist and non−specialist alike, many features of their skeletal anat− omy are not as easily recognized. There are several analyses of skel− etal morphology of extant lagomorphs (Bensley 1945; Crabb 1946