Faunal structures among European butterflies: evolutionary implications of bias for geography, endemism and taxonomic affiliation

European butterfly species have been classified, using four multivariate classification techniques, to faunal groups (a collection of species having similar distributions) each group having a unique geography (faunal element). Concordance occurs for 94% of species for at least three of the techniques. The faunal groups are biassed in geography, endemicity and taxonomic affiliation, indicating that they have historical and evolutionary significance. The inference is that a species by belonging to one faunal group, rather than to another, has a higher probability of being an endemic, and if it is not an endemic, then of evolving into one. This probability is influenced by affiliation to higher taxa, such as butterfly families, and thus by phylogenetic constraints. We argue that the fidelity of a species to a faunal element will affect its evolutionary pathway since, by belonging to a Faunal element, a species is subject to the distinctive processes linked to a unique landscape and its environmental conditions. Species have the capacity of switching between faunal groups owing to environmental changes impinging on their geographical ranges and epigenotypes. However, transfer of species across different groups are not of equal likelihood, being greatest between contiguous land elements and least between those restricted to islands. We suggest that conservation biology gives more attention to faunal structures; faunal groups have unique geography, are vulnerable to different macroevolutionary pressures and effectively underpin community assemblages within specific biotopes.