García-Navas, V. & Rodríguez-Rey, M. (2019) The evolution of climatic niches and its role in shaping diversity patterns in diprotodontid marsupials.Journal of Mammalian Evolution, 26, 479-492. DOI:10.1007/s10914-018-9435-z (IF2019 1,891; Q1 Zoology) NON-cE3c affiliated
The interplay between niche conservatism and niche evolution has been suggested to play a key role in shaping the biogeographical history of a given clade. Here, we integrate climatic data associated with the distribution range of 86 diprotodontid species and their phylogenetic relationships in order to examine the evolutionary dynamics of ecological niches of Diprotodontia and explore the link between diversification, niche evolution, and trends in biodiversity over space in this iconic group. Both mean annual temperature (MAT) and annual precipitation (AP) best-fitted punctuated modes of evolution indicate that climatic niche evolution in diprotodonts is speciational. Among-clade variation in rates of climatic niche evolution was correlated with variation in rates of lineage diversification, which reinforces the view that rapid shifts in climatic niches promote speciation. We found that both climatic attributes, AP and MAT, exhibited a pattern according to which species richness progressively declined along a gradient from ancestral to derived climatic conditions and, in turn, it was negatively correlated to niche breadth. However, correlation between niche breadth and niche position was not similar for both climatic traits, as these differ with respect to the relative position of the zone colonized by the most recent common ancestor within its corresponding axis. Diprotodontia diversity decreased while phylogenetic clustering increased, suggesting that niche conservatism associated with ancestral climate probably drives most of variation in species richness in this region. Our study shows that the diversification of diprotodontid marsupials appears to have occurred against a background of moderate phylogenetic niche consevatism, which largely determines the current distribution of this group.