Beetles (Insecta: Coleoptera) are among Earth’s most taxonomically and chemically diverse lineages, whose defensive secretions have fascinated evolutionary biologists since the time of Darwin. Over the past century, significant progress has been made in characterizing coleopteran defensive bouquets, validating compounds’ ecological functions, and describing the gross morphology of the glands that synthesize, store, and secrete them. By comparison, we understand little about the biosynthesis of these compounds or the evolution of exocrine gland structure, despite their importance to the biology of chemically defended species.

In this seminar, Adam will highlight key findings from six years of research aimed at improving our understanding of these and other facets of insect exocrine gland biology. Specifically, candidate molecular mechanisms underlying organic acid and quinone biosynthesis in ground beetles (Carabidae) and darkling beetles (Tenebrionidae) will be discussed. Additionally, patterns and mechanisms of exocrine gland structural evolution, including the repeated gain and loss of discrete traits and notes on adaptations to defensive chemical storage, will be described.