A functional analysis of the contribution of climatic niche divergence to adaptive radiation

A functional analysis of the contribution of climatic niche divergence to adaptive 1 radiation 2 22 23. CC-BY-NC-ND 4.0 International license peer-reviewed) is the author/funder. It is made available under a The copyright holder for this preprint (which was not. Abstract 24 Analyses of evolutionary radiations have traditionally focused on traits related to 25 resource acquisition, habitat use, and mate choice. Nonetheless, incorporation of climatic 26 niche divergence has become more common in recent years, driven by the development 27 of correlative ecological niche models (ENMs) that allow niche characterization based 28 solely on geo-referenced locality data. However, ENMs require no data on organismal 29 traits that link climatic conditions to performance, and thus have little to say about how 30 organisms phenotypically adapt to different climatic conditions, what the performance 31 consequences of phenotypic divergence are, and how phenotypic divergence influences 32 resource partitioning within communities of co-occurring species. Here, we conduct a 33 functional (i.e., physiological) analysis of climatic niche divergence within Greater 34 Antillean Anolis radiations. We find that physiological divergence occurred repeatedly 35 within these radiations, that there are performance consequences of physiological 36 divergence within natural habitats, and that physiological divergence facilitates species 37 coexistence within species-rich communities. We also use phylogenetic methods to 38 compare rates of evolution of ecologically relevant physiological and morphological 39 traits, and find that physiology has evolved either more slowly or as fast (but not faster) 40 than morphology. Our analysis demonstrates the benefit of a functional approach to 41 understanding macroevolutionary patterns of climatic niche divergence. 42 43 44 45 46. CC-BY-NC-ND 4.0 International license peer-reviewed) is the author/funder. It is made available under a The copyright holder for this preprint (which was not .