Wing-pattern-specific effects of experience on mating behavior in Heliconius melpomene butterflies

Many animals have the ability to learn, and some taxa have shown learned mate preference. This learning may be important for speciation in some species. The butterfly Heliconius melpomene is a model system for several areas of research, including hybridization, mate selection, and speciation, partially due to its widespread diversity of wing patterns. It remains unclear whether these butterflies can learn to prefer certain mates and if social experience shapes realized mating preferences. Here we test whether previous experience with a female influences male mate preference for two different H. melpomene subspecies, H. m. malleti and H. m. rosina. We conducted no-choice behavioral assays to determine if latency to court and whether males courted (vs no courtship) differed between naive males and males with previous exposure to a young, sexually mature, virgin female. To test whether assortative courtship preference is learned in H. melpomene, males were either paired with a female who shared their phenotype or one who did not. Naive H. m. malletti males courted assortatively, while naive H.m. rosina males did not. Experienced H. m. malleti males reduced their courting relative to naive males, suggesting that social experience with a sexually mature female that does not result in copulation may be perceived as a negative experience. In contrast, experienced H. m. rosina males exhibited similar courting rates to naive H. m. rosina males. Our results suggest that social experience can influence male mating behavior in H. melpomene and that behavioral plasticity may differ across populations in this species.