A test of the Resource´s and Bergmann's rules in a widely distributed small carnivore from southern South America, Conepatus chinga (Molina, 1782) (Carnivora: Mephitidae)

SCHIAFFINI, MAURO I.

MAMMALIAN BIOLOGY

ELSEVIER GMBH

Año: 2016 vol. 81 p. 73 - 81

1616-5047

Bergmann?s rule is one of the most known biological rules and relates the body size variation to changesin latitude or temperature. Most recently, a ?resource rule? had been presented, which explains severaltrends in body size, as a consequence of availability of resources. South American Conepatus chinga is oneof the most widespread small carnivores in the Neotropics, being geographically distributed from Perúand Brazil to southern Argentina and Chile. This widely distributed species encounters a high environ-mental variability, which could affect body size and morphological variations. Here, I analyze geographicalpatterns of variation in body size and morphology estimated using a geometric morphometric approachfrom museum specimens. The associations between geographical patterns of variation in body size andmorphometry and climatic and/or environmental variables were evaluated, using several databases andmultiple regressions and redundancy analysis. Throughout the study, the presence of spatial autocorre-lation was analyzed, and Spatial Eigenvector Mapping (SEVM) was used. The arid diagonal was identifiedas containing the smaller specimens of C. chinga, primarily related to net primary productivity (NPP).Bergmann?s rule seems not to be valid for this species. Instead, evidence seems to support the ?resourcerule? as the primarily explanation for body size variation. A lower amount of morphological variationwas explained by NPP, mainly related to relative size variation of premolar and molars.