The impact of body temperature on predation avoidance behaviour in a wild insect
Ruonan Li, Rolando Rodríguez‐Muñoz, Tom Tregenza
Abstract
Body temperature is critical to survival, growth and reproduction in all animals. In ectotherms, key fitness-related traits such as the capacity to escape from predators are expected to depend upon body temperature. Relationships between temperature and predator escape behaviours have been found in lizards. However, despite their central role in terrestrial ecosystems, we know very little about how temperature affects the capacity of insects to escape predators in nature. We studied wild crickets, Gryllus campestris , in a meadow in northern Spain where they respond to potential predator attacks by fleeing into a burrow. We used a high-speed video camera to measure how fast male and female crickets ran in response to a predator stimulus over a range of directly measured body temperatures. We found that females ran faster as their body temperature rose, whereas males did not change their escape speed with temperature. Our findings suggest that the trade-off that insects face between running speed and investment in other capacities results in differences between the sexes in the extent to which they can exploit higher temperatures to run faster. Our findings illustrate that changing temperatures will have effects on behaviours in ectotherms that are difficult to predict. • The impact of body temperature on antipredator behaviour is poorly understood. • We studied the escape responses of wild crickets in a Spanish meadow. • Body temperature was dependent on solar radiation and substrate temperature. • Warmer female crickets escaped faster but male speed was temperature independent. • No sex differences were found in other aspects of predator avoidance.