RESPONSES OF NAIVE LIZARDS TO PREDATOR CHEMICAL CUES

The ability to recognize chemical cues from predatory snakes is congen ital in the common lizard Lacerta vivipara. This conclusion follows fr om a series of experiments in which we observed the behavior of naive lab-born lizards in terraria that had previously been inhabited by pre datory snakes. Chemicals from both the viper Vipera berus (a sympatric predator) and the smooth snake Coronella austriaca (an allopatric sau rophagic snake) elicited a sharp increase in tongue-flick rates. The l izards, when confronted with snake chemicals, exhibited an increased n umber of foot shakes, tail vibrations and starts, and moved about in a strange, jerky way. In these aspects, the behavioral response of juve nile lizards resembled that of adults. The only quantitative age-relat ed difference concerned thermoregulatory behavior: whereas juveniles r efrained almost completely from basking in the presence of snake chemi cals, adult lizards basked equally long in snake and control experimen ts.