Effects of morphology, substrate use, and potential trade-offs on locomotor performance during multiple modes of snake locomotion

Question: How do morphology, substrate usage, and biomechanical constraints (i.e. trade-offs) influence locomotor performance of multiple modes of snake locomotion? Data studied: Nine morphological traits, substrate preferences and use, and locomotor performance (maximal speed and endurance) of four modes of locomotion (terrestrial lateral undulation, swimming, concertina, and arboreal) in five species of North American snakes. Search method: Principal component analysis and regression models to determine whether morphological differences were associated with speed and endurance of each mode of locomotion. Linear regressions to relate time spent on terrestrial, aquatic, and arboreal substrates to performance during modes used to traverse each substrate. Determine relationships between performance of different modes to identify potential trade-offs. Each species was analysed separately. Conclusions: Morphology significantly influenced size-relative, maximal speeds differentially across the various modes of locomotion and species, especially during modes that each species often utilizes in nature. Relationships between locomotor performance and substrate use exist, but patterns differed among species. Few trade-offs in performance were detected between modes for any species.