Meeting Abstract

S6-4  Tuesday, Jan. 5 10:00  Evolutionary endocrinology of dispersal polymorphism in insects ZERA, A.J.; Univeristy of Nebraska

Studies of dispersal polymorphic insects have and continue to contribute significantly to the development of evolutionary endocrinology. This talk will briefly summarize key early and current studies, and future directions, with a focus on evolutionary-endocrine studies of wing-polymorphic and phase-polyphenic insects. Classic studies of juvenile hormone (JH) and its regulators in wing-polymorphic Gryllus crickets were the first to provide a deep integration of quantitative genetics and endocrinology by estimating, for the first time, key quantitative genetic parameters for endocrine traits in non-domestic animals, showing how artificial selection can modify endocrine function, and identifying genetic correlations between endocrine and important life history traits and trade-offs. Recent detailed studies of JH signaling in G. firmus have identified unexpected morph-specific circadian rhythms for both JH titers and global gene expression, sparking an exciting expansion of evolutionary-endocrinology to include chronobiology (circadian rhythms). Recent neuroendocrine studies of locusts are providing detailed information on the mechanisms by which variable environmental signals are transduced via the endocrine system to guide fast-acting phenotypic transformations. These studies are important for understanding the mechanisms underlying adaptive polyphenism– a key topic in evolutionary biology. Finally, the endocrine regulation of morph development has been a longstanding topic in insect evolutionary endocrinology. Classic studies, which have focused primarily on the role of key metamorphic hormones such as JH and ecdysteroids, are being complemented by newer investigations focusing on other hormones, notably insulin-like peptides. These studies collectively provide important insights on how developmental and metabolic pathways are modulated to induce alternate morphs and how the expression of morph-specific traits are regulated during adulthood.