DANIEL, Peter/C; Hofstra University: Do Lobsters Increase Detection of Odorants by Waving Antennules? A 3D Kinematic Analysis

A major goal of chemosensory guidance research is to elucidate how animals extract information from the complex spatial and temporal structure of odorant plumes. Studies using lobsters as model organisms have examined orientation and locomotion of the whole animal as it encounters odorant plumes, as well as the flicking behavior of the antennules, the olfactory organ. Besides flicking, antennules can also move independently of general body movements by adjusting the joints of segments of the antennules more proximal to the body than the lateral and medial flagella that contain chemosensilla. These movements, referred to as antennular waving, have been observed anecdotally to increase in the presence of chemical stimuli. This hypothesis was tested by stereoscopic filming of antennular waving of spiny lobsters (N=8), Panulirus argus, towards control seawater and squid extract. 3D kinematic analysis software was used to measure the second by second coordinates of antennules and the body over 90-sec following stimulus introduction. Antennule coordinates were corrected for body position. Antennular waving and body movement generally increased upon addition of squid extract. However there was a strong correlation between antennular waving and body movement independent of stimulus type. Left and right antennular waving averaged over the 90-sec period were strongly correlated. However second by second velocities of the two antennules were not correlated. Thus left and right antennule movements, while not synchronized, are both tightly coupled to body movement. This results in increased spatial sampling due to body movement and antennular waving.