Phylogenetic Insights into Diversification

Species diversification—the balance between speciation and extinction—is fundamental to our understanding of how species richness varies in space and time and throughout the Tree of Life. Phylogenetic approaches provide insights into species diversification by enabling support for alternative diversification scenarios to be compared and speciation and extinction rates to be estimated. Here, we review the current toolkit available for conducting such analyses. We first highlight how modeling efforts over the past decade have fostered a notable transition from overly simplistic evolutionary scenarios to a more nuanced understanding of how and why diversification rates vary through time and across lineages. Using the latitudinal diversity gradient as a case study, we then illustrate the impact that modeling choices can have on the results obtained. Finally, we review recent progress in two areas that are still lagging behind: phylogenetic insights into microbial diversification and the speciation process.