For many animals, vibrations transmitted by air or water provide information about the local three-dimensional environment. Often there are extremely complex mechanosensory systems integrating extremely complex stimulus fields. This collaborative research project exploits a small aquatic crustacean, a copepod, as a novel model system that can be considered much simpler than the insects and large crustaceans used in other analyses. The copepod brain has fewer than 1000 neurons and lives in a simple flow environment where the animal creates a feeding current across the antennae. This current has some local turbulence in the open, but is converted to a smooth laminar flow field across the antenna. Microscale hydrodynamics, receptor neurophysiology and behavioral studies are used to clarify the mechanisms that transduce the 3-D information of natural signals into a neural signal, and underlie behavior such as feeding or escape from swimming predators detected by this small but sophisticated mechanosensory system. Results will be important for understanding 3-D processing in mechanosensory systems, and there is potential impact beyond neuroscience to biological oceanography because of the importance of copepods in the food web, and potential impact on the design of biosensors and robotic sensory technology.
