Meeting Abstract
Insects routinely forage in complex sensory environments. Typically the search for a food or pheromone source begins with a whiff of odor, which triggers a flight response. Insects then track turbulent plumes of odor until they approach the vicinity of the odor source. However, pinpointing the precise location of the odor source requires the use of both visual and olfactory modalities. We have investigated the basic rules of this process in the fruit fly, Drosophila melanogaster specifically asking how these flies are able to determine the precise location of an odor source amidst a visually cluttered environment. Our experiments show that the decision of flies to land on a putative odor source is biased by the presence of other visual objects in its vicinity. Flies are more likely to land on visually distinct objects that are close to the odor source, if they are of a higher visual contrast. There are significant quantifiable alterations in their search trajectories based on the presence or absence of one or more visually-distinct objects in the vicinity of the odor source. Our experiments also indicate the possibility of olfactory “working memory” that enables them to continue their search even when the olfactory feedback is reduced or absent. Together, these results allow us to gain insight into some basic rules that the flies may use to determine where the source of odor is located.
