Species with widespread distributions frequently show clines in body size across broad geographic areas. These clines may be the result of “ecogeographical rules” that describe spatial patterns of phenotypic diferences driven by environmental variation. Intraspeciic variation in body size, and the mechanisms causing this variation, have been poorly described in social wasps. This study examined ecogeographical patterns of body size for 12 native species and one non-native species of North American paper wasps (genus: Polistes) using body size measurements from > 14,000 pinned museum specimens. Intraspeciic body size was correlated with latitude, elevation, and broadscale climate variation. However, the direction of this relationship was idiosyncratic across species, with Bergmann’s clines and converse Bergmann’s clines equally represented. There was no evidence of a phylogenetic signal in the direction of the cline between body size and the environment. Within species, the worker caste and the reproductive caste showed the same direction of response between body size and latitude, although for most species the reproductive caste was larger than the worker caste. Intraspeciic variation in body size appears to be driven by diferences in the response among species to similar environmental variables but the mechanisms causing this variation remain unknown.

Whole boxes of pinned specimens of Polistes paper wasps from the collections at the American Museum of Natural History, the Cornell University Insect Collection, the Illinois Natural History Survey, the Smithsonian National Museum of Natural History, the Royal Ontario Museum, the University of Guelph Insect Collection, the University of Michigan Museum of Natural History, and the C.A. Triplehorn Insect Collection were photographed using a standarized set up. Boxes were placed inside of a light tent and photographed with a Canon 6D camera with an EF 24-105mm f/4L IS USM lens. The date and location of each specimen was transcribed from specimen labels. Latitude and longitude was determined using GEOlocate (http://www.geo-locate.org) and google maps (maps.google.com). Altitude and bioclim variables were obtained for each location. The head width, thorax width, and winglength of each specimen were measured in imageJ. The dataset includes original photographs of pinned specimens, measurements of size, and environmental variables. 

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