Living organisms are exposed to environmental cycles that result from the movement of the planet, as well as the movement of the moon. Most species have adapted to the solar day and the alternation of seasons and show oscillations in their physiology and behavior that are in synchrony with these cycles. Furthermore, species living at the seashore show biological oscillations in synchrony with the tidal cycle. Many of these daily and tidal biological oscillations are generated by biological clocks, which are endogenous biological processes that can oscillate in synchrony with the environment. Very little is known about the neural and molecular components that constitute these biological clocks in crustaceans of coastal habitats. The main goal of this project is to characterize the biological clocks responsible for daily and tidal rhythmicity in crustaceans living in coastal areas. Techniques will be used that involve isolation of specific genes involved in the clock mechanism and the study of behavioral rhythmicity in the laboratory. The studies will contribute to the understanding of biological timing systems and it will more specifically establish how species inhabiting the seashore have adapted to the environmental changes that result from the solar day and the tidal cycles. This project provides an excellent opportunity to study biological rhythms in a unique costal environment, namely the Pacific Northwest Coast and will provide a forum for both graduate and undergraduate student research training, by exploiting the research facilities at University of Washington and at Friday Harbor Laboratories.