Temporal dynamics of host‐marking in the tropical tephritid fly, Anastrepha ludens

Abstract. The temporal dynamics of host‐marking behaviour in the tropical tephritid fly, Anastrepha ludens (Loew), is described and used to formulate a model of control of marking behaviour. The following temporal patterns in host‐marking behaviour were observed. Time spent marking increased as Aludens females deposited clutches in a given fruit previously marked zero, one, two or three times. This trend was paralleled by an increase in the number of pauses in marking behaviour within the host‐marking bout (and hence an increase in the number of sub‐bouts separated by such pauses). Finally, within any given marking bout, the length of a sub‐bout diminished progressively. The length of a pause, by contrast, showed no significant trend. Based on these results, we propose that host‐marking pheromone, or HMP, while deterrent to females prior to egg‐laying, actually stimulates continued host‐marking behaviour after egg‐laying. We argue that host‐marking is regulated by sensory adaptation or habituation to HMP in conjunction with a dosage‐dependent restoration of inhibition of the motor pattern. Functional aspects of this pattern of motor control are discussed.