Diversity of motor responses initiated by a wind stimulus in the freely moving cricket, Gryllus bimaculatus

The behavioral responses to a wind stimulus were studied in the freely moving cricket, Gryllus bimaculatus. The observed responses included walking, running, jumping, turning, withdrawing, abdominal lifting, hind-leg lifting, kicking, cereal cleaning, antennal swinging, and ''no action'' and were classified into five behaviors as functional categories: escape, evasion, offense, surveillance and ''no action''. The elicitation of each type of behavior by an identical stimulus was variable and unpredictable. However, the stochastic approach showed that the probabilities of the behaviors converged in a series of responses obtained from one cricket and in mass response data collected from 48 crickets. These probabilities, the values calculated from the different populations, were the same. The statistical analysis, using the probabilities, revealed that the probabilities of these wind-evoked behaviors were affected by the intensity of the wind stimulus. The escape and ''no action'' were dominant, together constituting more than 60% of the total responses. The stimulus method and the animal conditions determining a high probability of escape are also discussed.