The ontogeny of feeding behavior. Maria A. Carvalho¹, Beryl Jones², Christen K. Mirth¹. 1) Instituto Gulbenkian de Ciência, Oeiras, Portugal; 2) Janelia Farm Research Campus, Ashburn VA, USA.

   In the wild, the choices an organism makes can be both crucial to its development and molded by its developmental stage. New insights in environmentally-regulated development and the characterization of some of the neurons involved in interpreting the chemical environment and regulating food choice in Drosophila provide an exciting opportunity to investigate how foraging choices in defined ecological contexts depend on developmental processes. We address this question in two ways, 1) By defining how development shapes the foraging preferences of larvae and 2) By identifying how development acts on the neural circuits that regulate foraging behavior to influence the stage-dependent food choices. Our results show that in the third larval instar, an environmentally sensitive developmental event called critical weight shapes foraging preferences. We observe larvae have different food preferences before and after this developmental milestone. Pre-critical weight larvae are more careful in their food choices and forage for longer periods until they burrow in the food substrate than their post-critical weight siblings. Additionally, we screened a Gal4 collection selected to have sparse patterns of expression in the central nervous system. Using a neuronal inhibition approach, we have identified neurons that are strong candidates to be part of the circuit regulating foraging behavior and food preferences throughout development. We predict these neurons either show different morphologies or different activities before and after critical weight, molding, in that way, larval feeding behavior according to its development.