LAY ABSTRACT IBN-98-8859 Integration of wind and sound sensory cues in the evasion system. For an animal under sudden attack by a predator, quick reaction is crucial. Even in the fastest evasive behaviors, integration of information from different sensory modalities may also be essential for behavior appropriate to the specific threat, yet this multimodal integration has rarely been studied behaviorally, and has never been examined in some seminal neuroethological systems. Bats use ultrasonic echolocation to home in on insect prey; some insects have evolved sensory systems and evasive behaviors to help them escape capture. Praying mantises have a cyclopean auditory system that is sensitive to ultrasound, and ultrasonic pulses trigger a complex, short-latency response that helps flying mantises survive bat attacks. We have recently shown that 1) the mantis cercal system is extremely sensitive to wind; 2) mantises respond to wind puffs when flying; and 3) strong wind accompanies bat attacks. Because it provides direction and distance information that the auditory system cannot, we hypothesize that the cercal wind detection system plays an important role in determining the timing, strength and nature of the mantis' evasive response. Using high-speed digital video, laser/solar cell movement detectors, and electromyograms, we will study the interaction of wind and sound stimuli in the evasive behavior of tethered, flying mantises in an anechoic chamber. Using electrodes implanted in a mantis tethered in a large flight room, we will monitor sensory CNS responses to both wind and sound as the insect is attacked by a flying bat. We will assess the efficacy of evasive behavior when only wind, only sound, or wind+sound information is available to the mantis CNS by staging encounters between free-flying mantises and bats in a large flight room. The results will provide the first data on CNS responses of an i nsect during an actual bat attack, and the first behavioral assessment of CNS integration of wind and sound stimuli in insect predator avoidance.
