Detailed Record



Environmental drivers of body size in North American bats


Abstract Bergmann's rule—which posits that larger animals live in colder areas—is thought to influence variation in body size within species across space and time, but evidence for this claim is mixed. We used Bayesian hierarchical models to test four competing hypotheses for spatiotemporal variation in body size within 20 bat species across North America: (1) the heat conservation hypothesis, which posits that increased body size facilitates body heat conservation (and which is the traditional explanation for the mechanism underlying Bergmann's rule); (2) the heat mortality hypothesis, which posits that increased body size increases susceptibility to acute heat stress; (3) the resource availability hypothesis, which posits that increased body size is enabled in areas with more abundant food; and (4) the starvation resistance hypothesis, which posits that increased body size reduces susceptibility to starvation during acute food shortages. Spatial variation in body mass was most consistently (and negatively) correlated with mean annual temperature, supporting the heat conservation hypothesis. Across time, variation in body mass was most consistently (and positively) correlated with net primary productivity, supporting the resource availability hypothesis. Climate change could influence body size in animals through both changes in mean annual temperature and resource availability. Rapid reductions in body size associated with increasing temperatures have occurred in short‐lived, fecund species, but such reductions will be obscured by changes in resource availability in longer‐lived, less fecund species. Read the free Plain Language Summary for this article on the Journal blog.
Authors Jesse M. Alston University of WyomingORCID , Douglas A. Keinath , Craig K. R. Willis , Cori L. Lausen ORCID , Joy M. O’Keefe ORCID , Janet Tyburec , Hugh G. Broders ORCID , Paul R. Moosman ORCID , Timothy C. Carter , Christopher P. Chambers ORCID , Erin H. Gillam ORCID , Keith Geluso ORCID , Theodore J. Weller ORCID , Douglas W. Burles , Quinn E. Fletcher ORCID , Kaleigh J. O. Norquay , Jacob R. Goheen University of WyomingORCID
Journal Info Wiley-Blackwell | Functional Ecology , vol: 37 , iss: 4 , pages: 1020 - 1032
Publication Date 2/12/2023
ISSN 0269-8463
TypeKeyword Image article
Open Access green Green Access
DOI https://doi.org/10.1111/1365-2435.14287
KeywordsKeyword Image Habitat Selection (Score: 0.53215) , Body Size (Score: 0.529362)