We know that phenotypic plasticity itself, a ubiquitous property of development, can undergo an enormous degree of evolutionary diversification, leading for example to the genetic canalization of a previously plastic phenotype. While the mechanisms regulating phenotypic plasticity are starting to be elucidated (see my section on Regulation of Plasticity), how these mechanisms themselves evolve and diversify remains poorly understood.
Horned beetles once again offer an excellent system to address this question given the outstanding diversity of nutrition-sensitive horn development in the genus Onthophagus. I focus on three species of horned beetles which exhibit diverse degrees of nutrition-responsive horn growth. I am currently working on using a comparative RNAseq approach to understand how patterns of gene expression underlying nutrition-responsive growth evolve in relation to the degree of morphological plasticity observed across closely related species. Come back in a few months for an update (or contact me)!