The influence of temperature on the defensive behavior in Tomodon dorsatus (Serpente, Dipsadidae)

Tetrapodes and ecotermicos vertebrates have a variable body temperature according to the temperature of the environment. Studies addressing lizards and snakes show that several behavior and functions of ectotermicos vertebrates suffer directly or indirectly influence of temperature on biological adequacy (fitness) (BARTHOLOMEW, 1982; HUEY, 1982; LILLYWHITE, 1987, MORI; BURGHARDT, 2001). Anti-predatory behavior constitutes a special case among behaviors influenced by temperature, because it seems to suffer from various types of changes in different groups of tetrápodes ectotermicos as salamanders (BRODIE JR.; DUCEY; LEMOS-ESPINAL, 1991), anuros amphibians (GOMES; BEVIER; NAVAS, 2002), lizards (RAND, 1964; HERTZ; HUEY; NEVO, 1982; CROWLEY; PIETRUSZKA, 1983), and snakes (FITCH, 1965; HERCKROTTE,1967; ARNOLD; BENNETT, 1984; SCHIEFFELIN; QUEIROZ, 1991; KEOGH; DESERTO, 1994; MORI; BURGHARDT, 2001).These studies show that the temperature affects behavioral responses both in terms of magnitude and quality, which suggests that the changes on the type of behavior with temperature be consistent with the effects of temperature on the behavioral performance. The current study tested through an analysis of the behavior Tomodon dorsatus snake (Dipsadidae) at different body temperatures when exposed to an external stimulus simulating a predatory attack. This species was chosen because it presents an enriched defensive repertoire (BIZERRA, 1998). For analysis, the defensive behaviors were classified into two main groups: \"aggressive\" and \"passive or escape as the behavior exhibited when the stimulus. During the study, it was observed that some animals were overly aggressive while others were extremely prone to flight. Therefore, besides the initial classification was made a separate analysis was to classify individual in two groups: DPA and FCP. This division that was useful to analyze the influence of temperature in different animals in their degree of aggressiveness. In this study we found that there was great individual variation in relation to antipredator behavior and the difference between individuals appears to be more significant when compared with the variation may be induced by temperature (AU)