Wild primate locomotor and quadrupedal variability




McNamara, Allison Joan

Journal Title

Journal ISSN

Volume Title



Primate locomotion is an interesting area of study due to primates’ variability in how they move. In this dissertation I present three research chapters that expand our understanding of how primates’ ecology, morphology, and phylogeny influence how they move in their natural habitats. Primate locomotion and kinematic research is critical for understanding how the interface of movement and ecology influence primate behavior and evolutionary history. Locomotor field studies and laboratory-based quadrupedal and kinematic studies have been popular for decades for understanding the evolutionary history of primate movement. However, merging field and laboratory methods for a more holistic and realistic understanding of primate locomotion and kinematics is a relatively new approach. In this dissertation’s second chapter, I merged laboratory and field methods to study the variability and flexibility of walking gait of ten platyrrhine species when walking on complex, natural substrates. The platyrrhines analyzed increased the overall variability of their walking patterns when moving over inconsistent substrates by making changes to different kinematic variables. Additionally, the platyrrhines in the sample used kinematic flexibility to adjust to inconsistencies while walking. In the third chapter I used the same video data set to analyze how seven platyrrhine species used their prehensile tails while walking in the wild. Prehensile tail use during walking was rare (12%), but was used most frequently when individuals walked on small and discontinuous substrates, and when using asymmetrical and lateral sequence walking patterns. Additionally, Atelinae species used their tails significantly more frequently than Cebinae, suggesting the different morphological features of Atelinae tails may influence non-mass-bearing prehensile tail use during walking. In chapter four, I conducted a meta-analysis of published primate locomotion field studies to understand the relationship between body mass and locomotor repertoires. According to my analysis of 40 years of published literature, body mass is not a reliable predictor variable of primate locomotion, and variability prevails across species of different sizes. Throughout this dissertation, the theme of primate locomotor variability emerges consistently yet in different ways (i.e., gait type, kinematics, tail use, locomotor repertoires) and is an exciting avenue for future research.



LCSH Subject Headings