No abstract

J. 1990: The mechanism of queen regulation of foraging by workers in paper wasps (Polzstes firscutus, Hymenoptera: Vespidae). Ethology 85, 335-343. AbstractWe examined how queens of the primitively eusocial wasp, Polisresfuscutus, stimulate foraging by workers in 10 small, post-worker-emergence field colonies. We experimentally increased colony needs, including needs of the brood, by removing a colony's most active foragers (thereby decreasing the colony's foraging rate), and found that the queen significantly increased both her level of activity and rate of aggressive interactions. Most aggressive interactions were directed at dominant workers. Removal of a colony's least active foragers, however, produced no such effect. O u r results, together with those of REEVE & GAMBOA (1983, 1987), indicate that queens are sensitive to brood needs, and that they behaviorally regulate worker foraging to match brood needs by increasing their level of activity and rate of aggressive interactions.

We observed in the field how resident females of the social wasp, Polistesfuscatus, treated female nestmates, non-nestmate first cousins, and unrelated nonnestmates. Behavioral observations were made |, 3, 4, 6, 7, 8, and 11 weeks after the emergence of a colony's first workers. Resident females were highly tolerant of female nestmates but highly intolerant of unrelated nonnestmates throughout the post-worker-emergence phase of the colony cycle. First cousins were treated either highly tolerantly or highly intolerantly, although most cousins (--~63%) were treated highly intolerantly. The treatment of cousins suggests that they are treated either tolerantly (like nestmates) or intolerantly (like unrelated non-nestmates) depending on whether they fall above or below an acceptance threshold, respectively. Resident females did not significantly change their tolerance of nestmates, first cousins, and unrelated females between different observation periods. However, all conspecifics were generally treated the most intolerantly 11 weeks post-worker-emergence, a time in the colony cycle when combs no longer contain brood. This decreased tolerance and its associated variance patterns late in the colony cycle are consistent with a more restrictive acceptance threshold. The optimal level of the acceptance threshold appears to be a compromise between the fitness consequences of accepting unrelated non-nestmates and rejecting one's nestmates. In a laboratory study, resident females were equally tolerant of female nestmates on and off the comb but significantly less tolerant of unrelated females on the comb than off the comb. Thus, females can modify their tolerance rapidly in different recognition contexts. In a second laboratory study, resident females were equally intolerant of unrelated females, regardless of whether they were from colonies 50 m or 50 km distant.