Individual recognition and individual identity signals in Polistes fuscatus wasps vary geographically

Geographic variation in animal phenotypes is common, yet we know surprisingly little about how communication varies across populations. Instead, most communication research focuses on one or a few populations and assumes recognition behavior is consistent across a species' range. Here, we show that individual identity signals and individual recognition vary across the geographic range of Polistes fuscatus wasps. P. fuscatus in MI and NY have variable facial patterns that signal individual identity and are used by receivers for individual recognition. However, P. fuscatus from Rothrock, PA lack individual identity signals, as they have less variable color patterns than P. fuscatus from MI. Further, P. fuscatus from PA are not capable of individual recognition. PA P. fuscatus do not learn and remember individual conspecifics during social interactions or during training. The MI and PA populations are genetically differentiated, but the differentiation is most likely geographic and not driven by differences in recognition. Overall, both signals and receiver responses vary across populations of P. fuscatus. Our results suggest that communication systems may rapidly evolve to produce variation in signals and receiver responses across a species' geographic range.