The developmental basis of phenotypic evolution in ants: hormones, genes, and epigenetics

Complex worker caste systems have contributed to the evolutionary success of advanced ant societies; however, little is known about the developmental processes underlying their origin and evolution. We integrate fieldwork with developmental genetics, endocrinology, epigenetics and phylogenetic analyses to understand how the environment acts during worker development to generate quantitative phenotypic variation within castes, and discrete variation between castes. First, we present a novel epigenetic mechanism that generates quantitative trait variation during worker development. Second, we discovered that the recurrent environmental induction of hidden ancestral developmental programs facilitates the adaptive evolution of novel worker castes. Collectively, we found that the environment can influence development through the integration of hormones, genes and epigenetic mechanisms to generate novelty within and between castes in ant colonies.