Meeting Abstract

P3.54  Saturday, Jan. 5  Do snakes possess locomotor adaptations in frequently-used microhabitats? Performance and energetic costs of different modes of locomotion in colubrid snakes GERALD, Gary W.*; CLAUSSEN, Dennis L.; Miami University; Miami University geraldgw@muohio.edu

Maximizing locomotor ability in all habitats an animal encounters throughout its normal activity range may not be possible if traits that enhance locomotion in one situation conflict with traits that enhance locomotion in another. Limbless animals, such as snakes, provide an excellent model to test these ideas, because of their propensity to use various modes of locomotion in different habitats. Five species of North American colubrid snakes (Elaphe guttata, Elaphe quadrivittata, Pituophis sayi, Nerodia sipedon, Thamnophis sauritus) that differ in patterns of microhabitat use were used to examine the hypothesis that the performance and energetics of various modes of limbless locomotion will reflect those patterns of microhabitat use (arboreal vs. terrestrial vs. aquatic). Locomotor performance was measured in all individuals from all five species during terrestrial lateral undulation, concertina, arboreal, and aquatic locomotion. Moreover, excess post-exercise oxygen consumption (EPOC) was measured following movements via each locomotor mode. The lowest energetic costs were experienced during swimming, followed by lateral undulation, concertina, and, lastly, arboreal locomotion. Results suggest that species display higher locomotor efficiencies during modes used most often in nature and display poorer locomotor efficiencies during those used more rarely. This indicates that trade-offs in locomotor abilities exist among modes of limbless locomotion and that this trade-off varies among species that differ in microhabitat use.