An evolutionary exploration of polyphenism in lepidopteran caterpillars

I review the phenomenon of larval polyphenism in Lepidoptera, noting examples of diet-, heat-, light-, and crowding-induced examples of phenotypic plasticity. Of special interest is the largely unheralded green-to-black polyphenism that occurs in many Lepidoptera prone to population outbreaks. We were able to induce green to black color changes in both directions by manipulating larval densities in the lab and field. The core of the presentation will examine the phylogenetic distribution of the green-to-black polyphenism in the Geometridae amd Noctuidae and consider adaptive explanations for this widespread color transformation.