Climatic niche attributes and diversification inAnolislizards

Abstract

AbstractAimThe aim of this study was to test the link between climatic niche dynamics and species diversification inAnolison islands and on the mainland. We tested the hypotheses that lineages in warmer climates and with narrow climate niches diversified more than lineages in cold climates and with broad climate niches. We also tested the hypothesis that species‐rich clades exhibit greater niche diversity than species‐poor clades.LocationNeotropics.MethodsWe collated occurrence records for 328Anolisspecies to estimate niche breadth, niche position and occupied niche space (as a proxy for niche diversity). We compared niche breadth between insular and mainlandAnolisspecies and amongAnolisclades, controlling for the potential confounding effect of range size. Using two approaches (clade‐based and QuaSSE) we explored the association between niche metrics and diversification rates inAnolislizards.ResultsWe found that CaribbeanAnolishad a narrower niche breadth and niche space occupation compared to mainland anoles after controlling for range size differences. There was a significant association between niche traits (mean niche position and niche breadth) and diversification in anoles. Anole lineages with narrow niche breadths and that occupy warmer areas exhibited higher speciation rates than those with broader niche breadths and that occupy cold areas. Similarly, clades with higher total diversification exhibit more niche diversity than clades with lower total diversification.Main conclusionsClimatic niche attributes play a role in anole diversification with some differences between mainland and insular anole lineages. Climatic niche differences between regions and clades likely are related to differences in niche evolutionary rates. This also suggests that climate plays a strong role in shaping species richness between and within mainland and islands.