Dr. Stephen M. Gatesy, Assistant Professor
Farlow, J.O., Gatesy, S.M., Holtz, T.R., Jr., Hutchinson, J.R., and Robinson, J.M. 2000. Theropod locomotion. American Zoologist 40:640-663.
SYNOPSIS. Theropod (carnivorous) dinosaurs spanned a range from chicken-sized to elephant-sized animals. The primary mode of locomotion in these dinosaurs was fairly conservative: Theropods were erect, digitigrade, striding bipeds. Even so, during theropod evolution there were changes in the hip, tail, and hindlimb that undoubtedly affected the way these dinosaurs walked and ran, a trend that reached its extreme in the evolution of birds. Some derived non-avian theropods developed hindlimb proportions that suggest a greater degree of cursoriality than in more primitive groups. Despite this, fossilized trackways provide no evidence for changes in stride lengths of early as opposed to later non-avian theropods. However, these dinosaurs did take relatively longer strides—at least compared with footprint length than bipedal ornithischian dinosaurs or ground birds. Judging from track-way evidence, non-avian theropods usually walked, and seldom used faster gaits. The largest theropods were probably not as fleet as their smaller relatives.
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