Copepods present a spectacular diversity of antennule and setal morphologies, orientations and degree of ornamentation. The causes and consequences of this diversity remain unexplored, but the staggering degree of morphological variation suggests structure-function relationships between mechanosensor properties and their sensory roles. Using copepods as a model system, this work will address the relationship between the shape of mechanosensory structures and their movement under non steady-state fluid conditions.
The goal of this project is to quantify the relationship between fluid motion and sensory morphology. Scanning electron microscopic measurements of the size and width of different setae and transmission electron microscopic measurements of cuticular thickness and the extent of the dendritic penetration up the shaft of individual mechanoreceptors will be made for three species of copepods. The force required to bend the seta and the physiological response of individual hairs to the well described flows created in the lab will be quantified with respect to the physical characteristics of the receptor. The empirical data will be used to build two interacting models: Finite Element Method (FEM) and Computational Fluid Dynamics (CFD). The FEM will be used to model the motion of individual seta with known morphology and bending characteristics while the CFD will be used to calculate the hydrodynamic force and torque applied to each region of the seta and the influence of the seta on the surrounding flow. These data are fundamental to understanding how these small, neurologically simple organisms can distinguish from the myriad of biologically and physically induced fluid movements.
The project includes several self-contained sub-projects that will provide exceptional opportunities for motivated undergraduate students to receive hands-on research experience learning sophisticated culturing techniques, the fundamentals of optics, microvideography, neurophysiology and the power of numerical simulations. High school students will also be invited into the lab to maintain cultures and help the undergraduate students with their projects. The PI will also work with the COSEE program (designed to bring ocean science to rural areas) and the ''Keller Bloom'' project which provides a week long science immersion course to gifted high school students from rural Maine. Results of the project will also contribute to the development of other BLOS educational and outreach programs, most notably the Phytopia project www.bigelow.org/phytopia/) and a weekly summer seminar series open to the public.
