The African Butterfly Bicyclus anynana: A Model for Evolutionary Genetics and Evolutionary Developmental Biology

Abstract

INTRODUCTIONThe butterfly model based on laboratory stocks of the African species Bicyclus anynana provides a special system for several reasons. First, a range of phenotypes has proven to be amenable to examination in this system. These include wing color patterns (including eyespots), seasonal forms, male androconia (secondary sexual traits), and a range of life-history traits (relevant to aging research). These phenotypes have a clear ecological relevance that is associated with dramatic differences in ecological environments represented by the dry and wet seasons in East Africa. Second, the Bicyclus genus and closely related genera from independent radiations in Asia and Madagascar are highly speciose, thereby providing opportunities to explore diversity among species for wing patterning, life histories, and male secondary sexual traits. There are also rich opportunities for examining interactions among all of these phenotypes and both natural and sexual selection. Moreover, the size of the organisms provides important practical advantages. B. anynana individuals are small enough to be readily reared in large numbers, but big enough to allow marking and tracking and also to facilitate such manipulations as microsurgical procedures on developing wing discs and the noninvasive sampling of hemolymph. Here, we explore the characteristics of B. anynana that enable integrative research linking variations among genotypes via development and physiology to variations in phenotypes and variations in adaptation to natural environments.