Using step width to compare locomotor biomechanics between extinct, non-avian theropod dinosaurs and modern obligate bipeds

摘要: How extinct, non-avian theropod dinosaurs locomoted is a subject of considerable interest, as the manner in which it evolved on line leading to birds. Fossil footprints provide most direct evidence for answering these questions. In this study, step width—the mediolateral (transverse) distance between successive footfalls—was investigated with respect speed (stride length) trackways Late Triassic age. Comparable kinematic data were also collected humans and 11 species ground-dwelling Permutation tests slope plot width against stride length showed that decreased continuously increasing extinct theropods (p < 0.001), well five tallest bird studied 0.01). Humans, by contrast, an abrupt decrease at walk–run transition. modern bipeds, patterns reflect use either discontinuous locomotor repertoire, characterized distinct gaits (humans), or continuous where walking smoothly transitions into running (birds). The are consequently inferred have had possibly including grounded running. Thus, features characterize avian terrestrial locomotion begun evolve early history.