Meeting Abstract

P2-39   -   Phototactic behavior of red-tail fairy shrimp (Branchiopoda: Anostraca) to broad and narrow spectrum light. Gaughan, M*; Lessios, N; Assumption University maria.gaughan@assumption.edu

Branchiopods are a group of crustaceans that are often found in temporary pond habitats, and are thought to predominantly use light cues for orientation. Fairy shrimp (Branchiopoda: Anostraca) have more spectral photoreceptor classes than might be expected given their reduced nervous systems for processing visual information. Other organisms with many spectral photoreceptor classes tend to have more complex nervous systems which process spectral information as color vision. It is likely that the visual systems of fairy shrimp are configured to use luminance vision, rather than color vision, to process information from their four spectral photoreceptor classes. We tested how the fairy shrimp respond to broad spectrum light using phototactic behavioral assays. Phototactic responses are found in most crustaceans that live in the water column. Light in natural environments varies, but tends to include a broad spectrum. It is unknown if broad spectrum light is processed by the same neural circuits as narrow spectrum light. Here, we present findings of phototactic responses of Streptocephalus. It has been previously reported that male fairy shrimp swim higher in the water column than females, which leads us to ask: what are the mechanisms responsible for this behavior, and what could be the possible fitness benefits?