Batesian mimicry, in which an undefended species resembles an unpalatable or otherwise undesirable prey item, is found throughout the tree of life. Mimicry is arguably best studied in butterflies, perhaps because it is relatively common, especially in the tropics, and because the earliest concepts of mimicry were based on lepidopteran examples. A handful of lepidopteran lineages have closely related mimetic species (and populations within species) with striking phenotypic differences between them. These apparently evolved because the prevalence of different potential “model” species in different areas selects for resemblance to the locally abundant model. Conversely, distantly related species can mimic the same widespread model and therefore resemble each other despite their geographic and phylogenetic distance. The butterfly genus Elymnias (Nymphalidae: Satyrinae) is a monophyletic group of Old World Butterflies that exemplifies an adaptive radiation of highly evolvable Batesian mimics. I will discuss the evolutionary history of this group as inferred with a robust molecular phylogeny and demonstrate remarkable phenotypic convergence and divergence. The most common and widespread species, Elymnias hypermnestra, is a facultative dual mimic. Males always mimic melanic Euploea species, but females can mimic melanic Euploea or orange Danaus depending on their locale. GWAS suggests that WntA may act as a genetic switch enabling females to mimic one model or the other. I speculate that the tremendous phenotypic variability in this group may result from deploying existing developmental pathways of wing pigments and pattern elements in novel combinations to produce rapid evolution of divergent mimetic phenotypes.
Adaptive radiation of Batesian mimics: Rapid divergent phenotypic evolution within and between species