Meeting Abstract

P2.99  Friday, Jan. 4  Capital vs. Income, Stable Isotopes Reveal Nutrient Allocation to Reproduction and Turnover in the Flesh Fly, Sarcophaga crassipalpis WESSELS, F. J.*; HAHN, D. A.; University of Florida; University of Florida fwessels@ufl.edu

Nutrient allocation patterns from both capital and income resources control the timing and magnitude of life history events. Understanding the origin and allocation of nutrients can elucidate physiological mechanisms underlying life histories. Capital and income nutrient pools were labeled by providing diets with distinct ratios of stable carbon and nitrogen isotopes. We found that when provided unlimited adult income, turnover in the reproductive pool was nearly complete. Eggs from two reproductive cycles were derived almost entirely from adult income. Further work focuses on the roles of lipids in this system. Lipids are essential macromolecules in development and reproduction, accounting for roughly half of the nutrients provisioned to insect eggs. Polar and neutral lipids were extracted and fractionated from reproductive and somatic tissues. The lipids from both tissue types were analyzed with an isotope ratio mass spectrometer in order to determine lipid turnover and allocation.