Many planktonic animals use setulose appendages to capture food or molecules, and to swim or propel water. Continued investigations into the physical mechanisms by which such appendages move water and separate particles from it will provide understanding of ecological and evolutionary meaning of shape and mechanical function of the appendages. The food- capturing second maxillae (M2's) of calanoid copepods are of primary importance because of the ecological importance of copepod feeding, and because of the diversity of morphologies and behaviors of M2's operatiang at a range of velocities where transitions in function are expected to occur. Dynamically- scaled physical models, based on data gathered from SEM and high-speed microcinematography of a variety of copepods, will be used: 1) to test predictions of mathematical models of the hydrodynamics of these appendages, and 2) to investigate the performance consequences of morphological features and behaviors too complicated to address mathematically. The investigation will show how defined aspects of body shape, appendage morphology, flapping kinematics, and motions of neighboring appendages affect the leakiness, capture range, particle-selectivity, drag, and power requirements of second maxillae.
