The Behavioral Repertoire of Dinoflagellates: High-Speed, High-Resolution Imaging of Ecologically Important Species-Species Interactions
Dinoflagellates are abundant and ecologically important species in marine ecosystems, and they play diverse roles in marine food webs. They may be best known to the general public as the organisms associated with periodic harmful algal blooms, or situations when toxins produced by fast-growing populations affect fish, shellfish, and marine mammals, as well as human use of coastal resources. These single-celled organisms have evolved a range of behaviors for obtaining nutrients from the environment, capturing prey, and evading predators. In this project, the investigators will use a newly developed high-speed microscale imaging system (HSMIS) in the lab and field to characterize dinoflagellate behaviors in unprecedented detail in space and time to understand ecologically important species-species interactions. The goal is to understand the relationships among behavior, morphology, and ecological function for dinoflagellates. More broadly, results will help explain processes that regulate the biomass of, distribution of, and chemical cycling by marine plankton. In addition, the investigators will develop and use a novel technology, provide research training for undergraduate students, and give demonstrations and lectures to the public. Dinoflagellates are one of the most abundant and ecologically important groups in marine ecosystems, playing diverse roles in marine food webs. These single-celled organisms have evolved an impressive repertoire of sensory, allelochemical, and behavioral capabilities for obtaining nutrients, capturing prey, evading predators, and competing against other organisms. This repertoire remains largely unexplored, however, in part because traditional microscopy limits observations at the relevant scales for the natural behavior of dinoflagellates. The investigators will conduct a laboratory and field project to use a high-speed microscale imaging system (HSMIS) to characterize dinoflagellate behavior in unprecedented spatial and temporal detail across a range of ecologically important species-species interactions. HSMIS overcomes several limitations inherent to traditional microscopy, such as wall effects due to small sample volumes, confinement to a horizontal field-of-view, and strong convection caused by using strong light. The goal is to achieve a mechanistic understanding of interspecies detection, avoidance, and capture. Observations will span a range of size scales and trophic levels and will include examples of different flagellar propulsive systems. Differences in swimming and flow will be used to understand trade-offs in body form and kinematics for nutrient uptake, resource competition, selective feeding, and predator/parasite avoidance.