Ant-related oviposition in a facultatively myrmecophilous butterfly

Oviposition location is an important decision for many insects and can have substantial effects on immature survival and growth. Species whose immature stages engage in mutualistic interactions with other organisms should prefer to lay eggs where high quality mutualist partners are present. I tested for ant-related oviposition in a myrmecophilous lycaenid, the Miami blue butterfly. Adult females that were not raised with Camponotus floridanus ants as larvae avoided ovipositing on host plants with ants present. However, adult females that were tended by ants as larvae showed no preference according to ant occupancy on host plants. Ovipositing females did not distinguish among host plants based on the presence of ant pheromones, nor did oviposition preference change as the adult butterflies senesced. These results indicate that gravid Miami blues do not prefer ovipostion sites occupied by mutualistic ant species. Indeed, female butterflies appeared to avoid the potentially aggressive C. floridanus workers, suggesting that ants may behaviorally deter females from ovipositing at sites that would benefit their larvae. However, I also found that experience with ants during the larval stage can mollify this innate aversion later in life, which is the first conclusive demonstration of natal habitat preference induction for ant mutualists among ant-associated lycaenid butterrflies.