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Abstract Signals and receiver responses often vary across a species’ geographic range. Effective communication requires a match between signal and receiver response, so there is much interest in the developmental mechanisms that maintain this link. Two potential mechanisms are genetic covariance between signal and receiver response and plasticity where individuals adjust their phenotype based on their partner’s phenotype. Here, we test how plasticity contributes to geographic variation in individual face recognition in Polistes fuscatus wasps. Previous work has shown that P. fuscatus from Michigan, USA (MI) have variable facial patterns used for individual recognition, while P. fuscatus from central Pennsylvania, USA (PA) lack variable facial patterns and are unable to learn individual conspecifics. We experimentally altered rearing environment, so wasps were either reared with their own population or in a common garden with wasps from both populations. Then, we tested the wasps’ capacity to learn and remember individual conspecific faces. Consistent with previous work, MI wasps reared with MI wasps were adept at learning conspecific faces, while PA wasps reared with PA wasps were unable to learn conspecific faces. However, MI and PA wasps reared in a common garden developed similar, intermediate capacity for individual face learning. These results indicate that individual face learning in Polistes wasps is highly plastic and responsive to the social environment. Plasticity in receiver responses may be a common mechanism mediating geographic differences in non-sexual signaling systems and may play a role in maintaining links between signals and receiver responses in geographically variable communication systems.
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Social Plasticity Enhances Signal-Preference Codivergence
The social environment is often the most dynamicandfitness-relevant environment animals experience. Here we testedwhether plasticity arising from variation in social environments canpromote signal-preference divergence—a key prediction of recentspeciation theory but one that has proven difficult to test in natural sys-tems. Interactions in mixed social aggregations could reduce, create,or enhance signal-preference differences. In the latter case, social plas-ticity could establish or increase assortative mating. We tested this byrearing two recently diverged species ofEnchenopatreehoppers—sap-feeding insects that communicate with plant-borne vibrationalsignals—in treatments consisting of mixed-species versus own-speciesaggregations. Social experience with heterospecifics (in the mixed-species treatment) resulted in enhanced signal-preference species dif-ferences. For one of the two species, we tested but found no differencesin the plastic response between sympatric and allopatric sites, sug-gesting the absence of reinforcement in the signals and preferencesand their plastic response. Our results support the hypothesis that so-cial plasticity can create or enhance signal-preference differences andthat this might occur in the absence of long-term selection against hy-bridization on plastic responses themselves. Such social plasticity mayfacilitate rapid bursts of diversification.
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- Award ID(s):
- 1855962
- PAR ID:
- 10507565
- Publisher / Repository:
- The University of Chicago
- Date Published:
- Journal Name:
- The American Naturalist
- Volume:
- 202
- Issue:
- 6
- ISSN:
- 0003-0147
- Page Range / eLocation ID:
- 818 to 829
- Subject(s) / Keyword(s):
- indirect genetic effects, mating preference, courtship signal, Membracidae, vibrational communication
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1086/726786
