Marine Invertebrate Physiology
Ph.D., DukeUniversity, 2004

Galbraith Marine Science Laboratory, Rm 106
727-864-7827 (Office), 727-864-7964 (Fax)
cohenjh@eckerd.edu

My research focuses on the physiology of marine invertebrate sensory systems.  I conduct experiments at shore-based laboratories and on ships at sea, employing microscopy, neurophysiology, behavior, and modeling approaches to understand structure, function, and evolution of sensory systems.  Much of my current work is on the visual systems of marine crustaceans (copepods, amphipods, shrimps, and crabs).  I am investigating what role(s) vision plays in the ecology of zooplankton communities in both the bright, warm surface ocean and the dim, cold deep-sea by characterizing adaptations (structural, physiological, behavioral) that are present to support visual function in these habitats.  Specific adaptations under study include the spectral sensitivity and temporal dynamics of photoreceptor cells, and the ability of animals to perceive ultraviolet, polarized, and biologically-produced light (bioluminescence).  Other projects include how organisms integrate multiple sensory modalities (vision, odor, etc.) to generate behavior; the role of sensory cues, such as the diel light cycle and tides, in migration behavior; and toxic effects of harmful algal species, such as the red tide dinoflagellate Karenia brevis, on zooplankton sensory ecology and behavior.

Courses offered:

Marine Invertebrate Biology, Comparative Physiology, Light and Life

Selected publications:

Cohen, J.H., P.A. Tester, and R.B. Forward, Jr. (in press) Sublethal effects of the toxic dinoflagellate Karenia brevis on marine copepod behavior. Journal of Plankton Research. 

Cohen, J.H. and T.M. Frank (2006) Visual physiology of the Antarctic amphipod Abyssorchomene plebs. Biological Bulletin 211:140-148. 

Cohen, J.H. and R.B. Forward, Jr. (2005) Photobehavior as an inducible defense in the marine copepod Calanopia americana. Limnology and Oceanography 50:1269-1277. 

Cohen, J.H. and R.B. Forward, Jr. (2005) Diel vertical migration in the marine copepod Calanopia americana. II. Proximate role of exogenous light cues and endogenous rhythms. Marine Biology 147:399-410. 

Forward, R.B., Jr., H. Diaz, and J.H. Cohen (2005) The tidal rhythm in activity of the mole crab Emerita talpoida. Journal of the Marine Biological Association of the U.K. 85:895-901.