The thermal environment may constrain the evolution of mating behaviour of ectothermal organisms. This study evaluates the impact of the thermal environment on the behaviour of male insects waiting for females at encounter sites. In the morning, males of the desert hackberry butterfly, Asterocampa leilia, perch and wait for females on or adjacent to the larval foodplant. Over the course of a morning as temperature increases, male body posture (wing position and orientation to sun) and perch preferences (perch height and perch insolation) change. The results show that the body temperature of males at perch sites is largely independent of air temperature (i.e. they thermoregulate) and the body posture and perch preferences change with air temperature. Observations on thermocouple-implanted models indicate that the observed changes in behaviour lead to decreases in operative thoracic temperature. The results indicate that changes in wing position, perch height preferences, and insolation preferences have adaptive thermal consequences that may constrain mate detection.
ASJC Scopus subject areas
- Ecology, Evolution, Behavior and Systematics
- Animal Science and Zoology