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RNA interference (RNAi) is a useful tool to assess gene function by knocking down expression of a target gene and has been used successfully in domestic and laboratory organisms. However, the use of RNAi for functional genomics has not fully extended into ecological model organisms in natural environments. Assessment of gene function in the wild is important because gene function can be environmentally and context dependent. Here, we present a case study using RNAi to assess gene function in wild paper wasps Polistes metricus, to test roles for two candidate genes ( NADH dehydrogenase ( NADHdh) and retinoid and fatty acid binding protein ( RfaBp)) in the development of reproductive castes. Previous studies have shown that these genes are upregulated in larvae that become queens compared to workers, but this pattern was reversed in the laboratory, making field-based studies necessary. We orally administered dsRNA to larvae in field colonies and found evidence of a short-term knockdown followed by a compensatory rebound in expression for RfaBp. We also observed the predicted worker-like decrease in lipid stores in NADHdh dsRNA treated wasps, suggesting a possible role for NADHdh in caste development. We discuss our results in the context of challenges for using RNAi for functional genomics in ecological model organisms in the field. [ABSTRACT FROM AUTHOR]

Taxonomic notes are presented on the Polistes stigma species group of the subgenus Polistella Ashmead, 1904, of the genus Polistes Latreille, 1802, in continental Southeast Asia. Three new species are described and illustrated: Polistes brunus Nguyen & Carpenter, new species; P. communalis Nguyen, Vu & Carpenter, new species; and P. tenebris Nguyen & Lee, new species. A key to these species is provided. Their nests are also described. [ABSTRACT FROM AUTHOR]

Additions to the knowledge of the paper wasp genus Polistes (Polistella) (Hymenoptera: Vespidae: Polistinae) from the northern part of Vietnam are presented. The males of two species, P. affinis Gusenleitner, 2006, and P. curcipunctum Nguyen, Kojima & Saito, 2011, are described for the first time. The nests of P. affinis Gusenleitner, 2006, and P. nipponensis Pérez, 1905, are also described. [ABSTRACT FROM AUTHOR]

In cooperatively breeding vertebrates, the existence of individuals that help to raise the offspring of non-relatives iswell established, but unrelated helpers are less well known in the social insects. Eusocial insect groups overwhelmingly consist of close relatives, so populations where unrelated helpers are common are intriguing. Here, we focus on Polistes dominula--the best-studied primitively eusocialwasp, and a species in which nesting with non-relatives is not only present but frequent.We address two major questions: why individuals should choose to nest with non-relatives, and why such individuals participate in the costly rearing of unrelated offspring. Polistes dominula foundresses produce more offspring of their own as subordinates than when they nest independently, providing a potential explanation for co-founding by non-relatives. There is some evidence that unrelated subordinates tailor their behaviour towards direct fitness, while the role of recognition errors in generating unrelated co-foundresses is less clear. Remarkably, the remote but potentially highly rewarding chance of inheriting the dominant position appears to strongly influence behaviour, suggesting that primitively eusocial insects may have much more in common with their social vertebrate counterparts than has commonly been thought. [ABSTRACT FROM AUTHOR]

Laboratory-based animal rearing is a common tool used to control environmental variation. However, important differences between lab and field environments may affect the biological relevance of results. Moreover, how lab rearing affects social dynamics in groups has received little attention. We investigated the effects of lab rearing on gene expression, physiology, behavior, and colony dynamics in a behavioral model system. The primitively eusocial paper wasp Polistes fuscatus has been studied in both lab and field and is an important system for understanding social evolution and caste (queen vs. worker) development. High nourishment has been implicated as a key factor in the development of prequeen ("gyne") traits. Because the nutritional environment is altered in the lab, understanding the effects of lab rearing on caste-related traits is critical to properly interpreting experimental results. Lab-reared wasps have access to ad lib food, whereas field colonies are likely food-limited. Our results support the hypothesis that lab rearing (and associated excess nourishment) biased the development of wasp physiology and to some extent, behavior, toward being more gyne-like. Expression levels of 4 caste-related genes, however, were in the opposite direction, toward more worker-like. Lab rearing also affected colony traits: lab-reared colonies dramatically halted nest construction and began producing male eggs 1 week later than field-reared colonies. These results demonstrate the complex effects of lab-rearing on eco-physiological traits of social species, and we discuss some pros and cons of studying ecological model systems in both lab and field settings. [ABSTRACT FROM AUTHOR]

We report a likely range expansion of the introduced social wasp Polistes major major Palisot de Beauvois (Hymenoptera: Vespidae) from Florida into southern Georgia, USA, as well as the first records of Polistes apachus de Saussure from Georgia. We also review what is known of the history of these species in the southeastern United States. [ABSTRACT FROM AUTHOR]

Abstract: Cooperative breeding decreases the direct reproductive output of subordinate individuals, but cooperation can be evolutionarily favored when there are challenges or constraints to breeding independently. Environmental factors, including temperature, precipitation, latitude, high seasonality, and environmental harshness have been hypothesized to correlate with the presence of cooperative breeding. However, to test the relationship between cooperation and ecological constraints requires comparative data on the frequency and variation of cooperative breeding across differing environments, ideally replicated across multiple species. Paper wasps are primitively social species, forming colonies composed of reproductively active dominants and foraging subordinates. Adult female wasps, referred to as foundresses, initiate new colonies. Nests can be formed by a single solitary foundress (noncooperative) or by multiple foundress associations (cooperative). Cooperative behavior varies within and among species, making paper wasps species well suited to disentangling ecological correlates of variation in cooperative behavior. This data set reports the frequency and extent of cooperative nest founding for 87 paper wasp species. Data were assembled from more than 170 published sources, previously unpublished field observations, and photographs contributed by citizen scientists to online natural history repositories. The data set includes 25,872 nest observations and reports the cooperative behavioral decisions for 45,297 foundresses. Species names were updated to reflect modern taxonomic revisions. The type of substrate on which the nest was built is also included, when available. A smaller population‐level version of this data set found that the presence or absence of cooperative nesting in paper wasps was correlated with temperature stability and environmental harshness, but these variables did not predict the extent of cooperation within species. This expanded data set contains details about individual nests and further increases the power to address the relationship between the environment and the presence and extent of cooperative breeding. Beyond the ecological drivers of cooperation, these high‐resolution data will be useful for future studies examining the evolutionary consequences of variation in social behavior. This data set may be used for research or educational purposes provided that this data paper is cited. [ABSTRACT FROM AUTHOR]