Using primate models to study the evolution of human locomotion: concepts and cases

Abstract

This note introduces the types of models used in functional morphological research in order to clarify certain semantic issues and to present some examples of the use of extant model species to contribute to our understanding of bipedal locomotion. The existing models fall into two broad categories: “abstraction models” are simplifications/abstractions of living organisms, whereas “comparative models” are extant organisms used as models or analogues for other organisms (e.g. extinct species). In a palaeoanthropological context, comparative models may be selected for their close (but always imperfect) resemblance to the organism of interest, but some atypical model species can also produce insights not despite their imperfect resemblance, but because of it. We present three examples of our own work on comparative primate models during studies of terrestrial bipedal locomotion in bonobos (Pan paniscus), olive baboons (Papio anubis), and white-handed gibbons (Hylobates lar), showing how they each provide insights into the evolution of human bipedal locomotion.