Responses of naive primates to snakes: experiments with selected species kept in Prague zoo

In the wild, snakes are known to elicit strong antipredator responses in primates. Primates often mob the snakes, which is also accompanied by loud calls. In evolution, the deadly threat posed by snakes goes as far as to the origin of placental mammals. In this study, the reactions of naïve individuals to snakes were tested. Naïve pigtail macaques (Macaca nemestrina) and mouse lemurs (Microcebus murinus) avoided the snake stimulus. For the macaques there was a longer latency to touch the rubber snake compared to the latency to touch the rubber lizard. The mouse lemurs avoided feeding on the side of experimental box where the snake odor was presented. The reactions of macaques and mouse lemurs were not accompanied by vocalizations and they seemed to be overall mild. Nevertheless, the snake stimuli used here were strong enough for these naïve primates. For ringtail lemurs (Lemur catta), the reactions to uncovering a hidden rubber snake was tested. But the lemurs showed no avoiding reactions. A question for further research is whether the different results for lemurs were not caused by different experimental procedure. As well as in macaques and mouse lemurs, the reactions seemed to be very mild. But no deeper analysis of the behavior was performed. Thus, a reaction could have been overlooked, which..