Niche breadth explains the range size of European-centred butterflies, but dispersal ability does not

Aim: The breadth of ecological niches and dispersal abilities have long been discussed as important determinants of species’ range sizes. However, studies directly comparing the relative effects of both factors are rare, taxonomically biased and revealed inconsistent results.
Location: Europe.
Time period: Cenozoic.
Major taxa: Butterflies, Lepidoptera.
Methods: We relate climate, diet, and habitat niche breadth and two indicators of dispersal ability, wingspan and a dispersal tendency index, to the global range size of 369 European-centred butterfly species. The relative effects of these five predictors and their variation across the butterfly phylogeny were assessed by means of phylogenetic generalized least squares models and phylogenetically weighted regressions, respectively.
Results: Climate niche breadth was the most important single predictor, followed by habitat and diet niche breadth, while dispersal tendency and wingspan showed no relation to species’ range size. All predicto..., For details see the published manuscript., Required software: Excel, R