PLASTICITY IN THE USE OF NESTMATE RECOGNITION CUES ALONG COLONY DEVELOPMENT IN POLISTES DOMINULA
Leonardo Platania, Alessandro Cini , Federico Cappa , Irene Pepiciello , Leonardo Platania , Leonardo Dapporto , Rita Cervo
Università di Firenze - Dipartimento di Biologia, Italy; Centre for Biodiversity and Environment Research, University College London, UK; Università di Firenze - Dipartimento di Biologia, Italy ; Università di Firenze - Dipartimento di Biologia, Italy ; Università di Firenze - Dipartimento di Biologia, Italy ; Università di Firenze - Dipartimento di Biologia, Italy ; Università di Firenze - Dipartimento di Biologia, Italy ; Università di Firenze - Dipartimento di Biologia, Italy
Nestmate recognition, i.e. the ability to discriminate nestmates from foreign individuals, has been traditionally deemed to be essentially based on chemical cues. Recent empirical evidence however indicates a plasticity in the use of different communication channels according to cues reliability in different contexts. In this perspective, an increasing interest in the use of visual signals, as alternative communication channel to chemical one, has shown that visual cues could play a key-role in recognition processes of social wasps. We tested the hypothesis of plasticity in the use of visual and chemical recognition cues in the social wasp P. dominula, in which the reliability of cues changes across the season. In the pre-emergence phase, colonies are characterized by the presence of few individuals, and the variability in the facial pattern might allow resident wasps to use visual cues for nestmate recognition. After workers emergence, the increase in colony members number reduces the reliability of visual cues, thus leaving the chemical ones as the most reliable. We thus predict a differential use of chemical and visual cues along the colony cycle. To test our predictions, we experimentally splitted visual and chemical cues of nestmates and non-nestmates and presented them alone or in combination (with coherent or mismatched cues) to resident wasps to test which cues were used in nestmate recognition in the two different colony stages and how the two different communication channels interacted. Our results show a differential use of visual and chemical cues according to colony phase: in the preemergence phase the visual cues appear to play a major role in the recognition processes; instead, in the post-emergence phase resident wasps seem to rely more on the use chemical cues. Our results support the hypothesis of a ductile, reliability-related use of recognition cues in this species.