Deep evolutionary experience explains mammalian responses to predators

Abstract

Prey may have ontogenetic experience, evolutionary experience, or both types of experiences with their predators and how such experiences influences their ability to identify their predators is of great theoretical and applied interest. We capitalized on predator-free exclosures containing populations of native burrowing bettongs (Bettongia lesueur) and introduced rabbits (Oryctolagus cuniculus) that ensured we had knowledge of our subjects’ ontogenetic experiences with predators and asked whether evolutionary experience influenced their visual predator discrimination abilities. Rabbits evolved with red foxes (Vulpes vulpes) and wolves (Canis lupus) but had less than 200 years of prior exposure to dingoes. The rabbit population we studied had been exposed to dingoes (Canis dingo) and foxes 8 months prior to our study and had heightened responses to red fox models, but not dingo/dog (Canis dingo/Canis familiaris) models. The insular burrowing bettong population had no ontogenetic exposure to mammalian predators, brief evolutionary exposure to domestic dogs and possibly dingoes, and a deeper evolutionary history of exposure to thylacines (Thylacinus cynocephalus)—another large mammalian predator with convergent body morphology to dingoes/dogs but no evolutionary or ontogenetic exposure to foxes. Bettongs showed a modest response to the dingo/dog model and no response to the fox model. These results are consistent with the hypothesis that deep evolutionary history plays an essential role in predator discrimination and provides support for the multipredator hypothesis that predicts the presence of any predators can maintain antipredator behavior for other absent predators. Prey may have ontogenetic experience and or evolutionary experience with their predators. How such experiences influence prey species’ ability to identify their predators is of significance to theory on the evolution of antipredator response and to improve the success of translocations and reintroductions for conservation purposes which often fail because of predation on predator naive prey. Here, we show that prey recognition for two prey species with limited or no ontogenetic exposure to predators, rabbits, and burrowing bettongs was greatest toward the predator to which they had the longest period of coevolution. The results are consistent with the hypothesis that evolutionary history plays an essential role in predator discrimination and provides support for the multipredator hypothesis that predicts the presence of any predators can maintain antipredator behavior for other absent predators.