A COMPARATIVE ANALYSIS OF THE ECOLOGICAL SIGNIFICANCE OF MAXIMAL LOCOMOTOR PERFORMANCE IN CARIBBEAN ANOLIS LIZARDS.

We examined the sprinting and jumping capabilities of eight West Indian Anolis species during three natural activities (escape from a predator, feeding, and undisturbed activity). We then compared these field data with maximal performance under optimal laboratory conditions to answer three questions: (1) Has maximal (i.e., laboratory) sprinting and jumping performance coevolved with field performance among species? (2) What proportion of their maximum capabilities do anoles sprint and jump in different ecological contexts? (3) Does a relationship exist between maximal sprinting and jumping ability and the proportion of maximal performance used in these contexts? Among species, maximal speed is tightly positively correlated with sprinting performance during both feeding and escape in the field. Sprinting speed during escape closely matches maximal sprinting ability (i.e., about 90% of maximum performance). By contrast, sprinting performance during undisturbed activity is markedly lower (about 32% of maximum) than maximal sprinting performance. Sprinting ability during feeding is intermediate (about 71% of maximum) between field escape and field undisturbed activity. In contrast to sprinting ability, jumping ability is always substantially less than maximum (about 40% of maximum during feeding and undisturbed activity). A negative relationship exists among species between maximal speed and the proportion to which species sprint to their maximal abilities during field escape.