Convergent evolution in lemur environmental niches

Aim: To test the hypothesis that adaptive convergent evolution of climate niches occurred in multiple independent lemur lineages. 

Location: Madagascar

Taxon: Lemurs

Methods: I collected climate and altitude data from WorldClim and summarized the niches of almost all living lemurs (83 species) into phylogenetically-controlled principal components. To test for convergent evolution, I searched for multiple, similar climate optima using multi-peak Ornstein-Uhlenbeck models (surface, l1-ou, bayou). I compared the observed level of climate convergence to that simulated under neutral and single-optimum models. To test if behavioral or morphological traits were related to climate niches, I used phylogenetic regressions with activity pattern, diet, and body size.

Results: From an ancestral niche with high rainfall and low seasonality, four lemur lineages independently converged on climate niche optima characterized by high temperatures and low rainfall, supporting adaptive evolution...