Meeting Abstract
P2.96A Monday, Jan. 5 Genetic and Nutritional Influences on Male Reproductive Performance in Tribolium flour beetles MING, Q.L.*; TIGREROS, N.; FEDINA, T.; LEWIS, S.M.; Tufts University, Medford, MA 02155 USA qinglei.ming@tufts.edu
The evolutionary maintenance of genetic variation for male sexual traits in the face of directional selection represents a long-standing paradox. One possible mechanism responsible for maintaining such variation is genotype-environment interactions (GEI), which can maintain variation because some male genotypes perform better in certain environments while different genotypes do better in other environments. However, few studies have examined the role of GEI in maintaining variation in male sexual traits. In these experiments, we used Tribolium flour beetles to examine the contribution of genotype and nutritional environment to several larval and adult traits as well as to male mating and post-mating reproductive performance. Using a split-brood design for siblings reared on high, medium and low nutritional diets (created by manipulating ratio of flour to non-nutritive microcrystalline cellulose), we estimated genetic and environmental variation and GEI. Quantitative genetic analyses revealed significant genetic and nutritional contributions to larval mass, larval growth rate, and larval development time. Male reproductive performance was influenced both by diet, which affected mating rate, and genotype, which affected insemination success. Nutritional quality of the rearing environment had a significant effect on both adult resistance to starvation and weight reacquisition. The absence of GEI for most male traits suggests that other mechanisms, including condition-dependence, may be responsible for maintaining trait variation in Tribolium flour beetles. This study not only helps us understand how different environments influence Tribolium male traits and reproductive performance, but also provides new insights into how sexual selection changes across different environments.
