5 | CONCLUSION
Our study highlights the importance of the mechanistic links of colour lightness and body size with the temperature regime which shapes the biogeographical patterns of dragon- and damselflies (Odonata). Colour- and size-based thermoregulation were by far the dominant mechanisms shaping the composition of assemblages of odonates, although other functions of body size and colour lightness seemed to influence the geographical patterns of both traits to some extent. The consistency of our findings together with the results of a number of macroecological analyses underlines the general importance of thermal melanism and Bergmann’s rule for ectothermic organisms. However, besides highlighting the crucial role of traits involved in thermoregulation in shaping the distribution of odonate species, our results indicate that difference in species’ dispersal propensities embedded in the spatio-temporal stability of their habitats contributes to explaining the scatter around the considered trait-environment relationships as well as to differences in the relative contributions of climatic predictors. Thus, thermal adaptations seem to be of similar evolutionary importance for lentic and lotic species but a greater dispersal ability of the former in combination with the climatic history of Europe seem to have allowed them better cope with historical climatic changes.