Neural dissection of active predator avoidance behavior in Drosophila. Claire J. Manson-Bishop, Gregg W. Roman. Biology and Biochemistry, University of Houston, Houston, TX.

   The response of Drosophila melanogaster to predators has not only ethological relevance, but will contribute toward the establishment of an anxiety-like behavioral model within this organism. Such a model will enable the dissection of the molecules and neurocircuits involved in the modulation of anxiety. We have characterized the behavioral response of Drosophila to predators; it is the goal of these experiments to begin to dissect the neurochemicals implicated in these behaviors. For these experiments, we study Drosophila within the circular open-field paradigm using two predators, the Pantropical jumping spider (Plexippus paykulli) and the Carolina mantid (Stagmomantis carolina); both predators are capable of capturing and preying upon Drosophila in large arenas. Wild type Canton-S actively avoid a predator caged within the center of a circular open-field arena. Using mutant norpA⁷;orco² flies that are both blind and broadly anosmic, we show that the sensory modalities of sight and smell are together necessary for the detection and avoidance of predators. Toward the elucidation of the neurochemicals responsible for predator avoidance, we sought to determine whether serotonin plays a role using the UAS-gal4 binary system. Modulating the activity of serotonergic neurons did not alter predator avoidance, suggesting that serotonin does not affect this behavior.