Dylan Padilla, John VandenBrooks, Marla B Sokolowski, Michael J Angilletta Jr

A wealth of evidence indicates that the existence of active foragers and sit-and-wait foragers is widespread in nature. While active foragers visit foraging sites and leave them randomly, sit-and-wait foragers only do so if the benefit of leaving exceeds the cost. This dichotomy has been documented in the larval and adult stages of Drosophila melanogaster. For instance, when exposed to a nutrient-rich substrate, some individuals travel significantly longer distances than others. In this study, we designed an experiment to evaluate whether the distribution of food in the environment alters the foraging behavior. If some individuals acquired more food than others in a given environment, we further examined whether variation in the life history occurred among them. Our results indicated that foraging behavior is a plastic trait remarkably shaped by the distribution of food in the environment. We found that active foragers and sit-and-wait foragers increased their locomotion when food was patchy rather than clumped, but the locomotion of active foragers was higher overall. Interestingly, we found no differences in the life history between the two foraging strategies. We suggest that foraging actively should evolve faster anyway because it facilitates local adaptation via founder effect and gene flow.