Fig. 4.

Conditioned suppression should render social effects more detectable when aversive stimuli are present. (A) Safe environment. We assume that bees have learned to associate the feeding holes in artificial flowers with sucrose rewards. Therefore, in the absence of aversive stimuli, the chances of acceptance on encountering a flower are high (here set at 0.9, for illustration purposes). The presence of a demonstrator is also attractive (here set at 0.45), perhaps because bees have previously learned to associate conspecifics with sucrose. If two appetitive conditioned stimuli are presented together, the subject’s expectation is equal to their combined strength (62), so occupied flowers are very attractive, but a probability of acceptance cannot exceed 1. Thus, the detectable effect of demonstrator presence is small (arrow). (B) Dangerous environment. The presence of an aversive stimulus (the dangerous flower color) reduces all responses for food (here, suppression ratio has been set at 0.5). Thus, the difference in the probability of acceptance between the unoccupied and occupied flowers is now relatively more detectable (arrow).