The evolution of lycaenid caterpillars and ants: From mutualism to parasitism

The family Lycaenidae contains as many as a third of all butterfly species, and the caterpillars of the majority of these species associate either mutualistically or parasitically with ants. Lycaenid feeding preferences also range dramatically from feeding on plants to highly specialized forms of carnivory. A phylogenetic framework for the Lycaenidae permits a detailed analysis of the evolutionary dynamics of these relationships, and has uncovered evidence of historical constraint in patterns of host-ant choice among lycaenids as well as consistent patterns in the polarity of evolutionary change in the acquisition of predatory or parasitic lifestyles. Ants have played a significant role in the behavioral ecology of lycaenid caterpillars, and together with their host plants, can be considered as an ecological template against which the Lycaenidae have diversified.