Meeting Abstract
Different performance tasks can impose conflicting demands on the behavioral, skeletomuscular, and biochemical mechanisms underlying locomotor performance, resulting in trade-offs. However, when studying animal locomotion, performance trade-offs are often difficult to detect because of large variation in the quality, health, and motivation among individuals. There are likely many traits that enhance various types of performance without hindrance to others (e.g., larger muscle mass or increased metabolic efficiency), thereby making potential trade-offs between different performance tasks more difficult. We aimed to determine if locomotor trade-offs exist in snakes with and without taking individual performance quality into account. Using cornsnakes (Pantherophis guttatus), we quantified locomotor performance during 10 different locomotor modes/ecological situations. We hypothesized that functional trade-offs among pairs of locomotor modes/situations would be detected only after accounting for individual quality. We also expected to detect a generalist-specialist trade-off with quality-corrected speed data. We found no significant trade-offs among performance measures that were not corrected for quality. After taking individual quality into account, cornsnakes exhibit a specialist-generalist trade-off across all locomotor performance measures. We found a positive correlation between terrestrial lateral undulation and swimming. Significant negative correlations between lateral undulation and concertina, as well as between several measurements of arboreal performance, were found only after individual quality was accounted for. These results strongly suggest that locomotor performance should be corrected for individual quality before making comparisons among modes and species.
