Body size clines in the European badger and the abundant centre hypothesis

Abstract

Aim To test the abundant centre hypothesis by analysing the physical and climatic factors that influence body size variation in the European badger (Meles meles). Location Data were compiled from 35 locations across Europe. Methods We used body mass, body length and condylo‐basal length (CBL) as surrogates of size. We also compiled data on latitude, several climatic variables, habitat type and site position relative to the range edge. We collapsed all continuous climatic variables into independent vectors using principal components analysis (PCA), and used a general linear model to explain the morphometric variation in badger populations across the species’ range. Results Body mass and body length were nonlinearly and significantly related to latitude. In contrast, CBL was linearly related to latitude. Body mass changed nonlinearly along the temperature (PC1) gradient, with the highest values observed at mid‐range. Furthermore, body mass, body length and CBL differed significantly among habitats, with badgers showing larger size in temperate habitats and core areas relative to peripheral zones. Main conclusions Our analysis supports the nonlinear pattern predicted by the abundant centre hypothesis only for body mass and body length. These results imply that individuals are largest and heaviest at the centre of the climatic range of badger distribution. Variation of CBL with latitude follows a linear trend, consistent with Bergmann’s rule. Our results provide mixed support for the abundant centre hypothesis, and suggest food availability/quality to be the main mechanism underlying body size clines in this species.

Orchelimum superbum(Orthoptera: Tettigoniidae: Conocephalinae) on the Great Plains of North America

“…The abundant center hypothesis, which predicts that body size and abundance will be greater in the center of an organism's distribution than at the edges (e.g., Samis & Eckert 2007, Virgos et al 2011, agrees with our observations of body size variation, which showed a trend of increase with increasing elevation (a proxy for distance from the coast) rather than a general south to north increase as predicted by Bergmann's rule. Regarding abundance, orthopterists reported O. superbum to be rare at the type locality in New Jersey (Rehn & Hebard 1915) and elsewhere along the Atlantic and Gulf Coasts (T.J. Walker and G.K. Morris, pers.…”

In situ adaptive response to climate and habitat quality variation: spatial and temporal variation in European badger (Meles meles) body weight

“… They are territorial central place foragers that utilize fixed burrows (‘setts’) that are critical for their survival (Byrne et al ., ; Noonan et al ., ) – consequently, they do not migrate in response to changing conditions. Their body weight fluctuates naturally across seasons, coupled with changes in activity within temperate and northern latitudes (Kowalczyk et al ., ; Noonan et al ., ). There is substantial literature linking badger population dynamics to weather conditions (Nouvellet et al ., ), trends in climate (Macdonald & Newman, ), patterns of weather variability (Macdonald et al ., ) and energetics (Noonan et al ., ) – capable of influencing their biogeographical distribution (e.g. Bevanger & Lindstrom, ; Virgós et al ., ), all substantially relating to their diet – in particular, a preference for earthworms (Kruuk & Parish, ; Johnson et al ., ; Cleary et al ., ). Badger distributions and regional abundances are subject to various management (culling) strategies in response to their role as a host species for Mycobacterium bovis, the causative agent of bovine tuberculosis (bTB), linked to cattle herd bTB risk epidemiology (Donnelly et al ., ; Griffin et al ., ; Byrne et al ., ). …”

Biogeographic variation in the baboon: dissecting the cline

“…Baboon size and shape are undoubtedly spatially variable, but it is not clear whether this variation has arisen in response to environmental pressures, as has been argued to be the case in other instances of clinal variation (James, ; Burnett, ; Ferguson & Larivière, ; Virgós et al. ). This seems likely in baboons as they are extremely responsive to the environment, which modulates group size (Byrne et al.…”