INFLUENCE OF DIFFERENT EYE REGIONS ON STRIKING, SIZE DISCRIMINATION AND HABITUATION IN MANTIS SHRIMP

The striking behaviour of several species of Gonodactylus, of Pseudosq uilla ciliata and of Odontodactylus scyllarus was studied in unharmed animals and in animals with modified eyes and/or antennal scales and a ntennae. Modifying sensory inputs increases aggressiveness i.e., strik ing frequency. Precision of hitting the centre of a target disk increa ses if the middle bands of the eyes are covered and in one-eyed animal s without antennal scales, and decreases if the sides of the eyes are covered. Habituation occurs if trial intervals are shorter than fiftee n minutes. Localization and hitting a target in a critical zone should be automatic according to a previously developed model. According to the experiments reported here an additional, learned identification se ems to be necessary for the decision to strike. The capacity for learn ing is shown by habituation. The possible mechanisms for instantaneous and simultaneous localization and identification of a prey (even by a nimals missing large parts of the eyes) in parallel, nervous subsystem s is discussed.