Bergmanns rule in mammals: a cross-species interspecific pattern

Although Bergmann’s rule – stating that among closely related species, the bigger ones will inhabit the colder climates/higher latitudes – was formulated for inter-specific comparisons, most analyses that tested this pattern in mammals were on an intra-specific level. To date, no large-scale taxonomydriven cross-species evaluation of the pattern predicted by Bergmann exists. Here we show, in a dataset comprising 3561 mammal species from 26 orders, that while there is no significant correlation between latitude and body mass using conventional methods, this correlation is highly significant when the phylogenetic structure of the dataset is accounted for, thus supporting Bergmann’s claim that the rule only applies to closely related species. Analyses of different subsets indicate that the Bergmann’s rule is evident across a variety of latitude ranges. In many taxonomic subsets, when analysed alone, there is no significant correlation between body mass and latitude. In combination with both the significant relationship in the overall dataset and with results of intra-specific analyses from the literature, this suggests that Bergmann’s rule describes a fundamental principle within mammals, but that its expression has been modified by a variety of factors during mammalian diversification yet to be resolved. DOI: https://doi.org/10.1111/j.1600-0706.2013.00463.x Posted at the Zurich Open Repository and Archive, University of Zurich ZORA URL: https://doi.org/10.5167/uzh-81100 Accepted Version Originally published at: Clauss, Marcus; Dittmann, Marie T; Müller, Dennis W H; Meloro, Carlo; Codron, Daryl (2013). Bergmann�s rule in mammals: a cross-species interspecific pattern. Oikos, 122(10):1465-1472. DOI: https://doi.org/10.1111/j.1600-0706.2013.00463.x Oikos 1 Bergmann’s rule in mammals: a cross-species interspecific pattern 2 3 Marcus Clauss, Marie T. Dittmann, Dennis W. H. Müller, Carlo Meloro, Daryl 4 Codron 5 6 Clinic for Zoo Animals, Exotic Pets and Wildlife, Vetsuisse Faculty, University of Zurich, 7 Winterthurerstrasse 260, 8057 Zurich, Switzerland 8 Institute of Plant, Animal and Agroecosystem Sciences, Swiss Federal Institute of 9 Technology, Universitätsstrasse 2, 8092 Zurich, Switzerland 10 National Park ‘Bavarian Forest’, Freyunger Str. 2, 94481 Grafenau, Germany 11 Dipartimento di Scienze della Terra, Universita` degli Studi Federico II, Largo San 12 Marcellino 10, 80138 Napoli, Italy 13 Florisbad Quaternary Research, National Museum, Bloemfontein, 9300, RSA 14 School of Biological and Conservation Sciences, University of KwaZulu-Natal, Private Bag 15 X01, Scottsville, 3209, South Africa 16 Department of Anthropology, University of Colorado at Boulder, Boulder, CO80309, USA 17 18 Running head: Bergmann’s rule in mammals 19