Detailed tracking of body and leg movements of a freely walking female cricket during phonotaxis

We describe a semi-automated tracking system for insect motion based on commercially available high-speed video cameras and freely available software. We use it to collect detailed three-dimensional kinematic information from female crickets performing free walking phonotaxis towards a calling song stimulus. We mark the insect's joints with small dots of paint and record the movements from underneath with a pair of cameras following the insect as it walks on the transparent floor of an arena. Tracking is done offline, utilizing a kinematic model to constrain the processing. We can obtain the positions and angles of all joints of all legs and six additional body joints, synchronised with stance-swing transitions and the sound pattern, at a 300 Hz frame rate. This data will be used in the further development of models of neural control of phonotaxis.

► A new experimental setup for tracking cricket kinematics during phonotaxis. ► High-speed stereo video from underneath the animal shows position of all leg joints. ► Semi-automated simultaneous tracking of 27 joint markers by fitting kinematic model. ► Output joint angles and positions, stance-swing transitions and sound pattern.