The function of environmentally acquired perfume blends in male orchid bees

Abstract

AbstractPerfume making by male orchid bees is a remarkable behavior giving rise to an entire pollination syndrome in the neotropics. Male orchid bees concoct and store perfume mixtures in specialized hind-leg pockets using volatiles acquired from multiple environmental sources, including orchids. However, the precise function and ultimate causes of this behavior have remained elusive. We supplemented maleEuglossa dilemmareared from trap-nests with perfume loads harvested from wild conspecifics. In dual-choice experiments, males supplemented with perfumes mated with more females, and sired more offspring, than untreated, equal-aged, control males. Our results demonstrate that male-acquired perfumes function as chemical signals emitted during courtship and received by females when selecting mates. Sexual selection might be a key agent shaping the evolution of perfume signaling.One-Sentence SummaryThe possession of exogenous volatiles increase male mating success and paternity in orchid bees.