Tanja Stadler: Recovering macroevolutionary processes using phylogenetic methods

Phylogenetic trees of present-day species allow the inference of the rate of speciation and extinction which led to the present-day diversity. Classically, inference methods assume a constant rate of diversification. I will present a new inference methodology which can estimate changes in diversification rates through time, can detect mass extinction events, and can account for density-dependent speciation. The method is based on an in-depth analysis of a birth-death process with birth and death parameters being a function of time and / or the number of alive individuals.

I use the method for testing the hypothesis of accelerated mammalian diversification following the extinction of the dinosaurs (65 Ma); none of the analyzed mammalian phylogenies showed a change in diversification rates at 65 Ma. Application of the method to bird data (Dendroica) reveals a density-dependent speciation process, agreeing with previous studies. The new method further allows to quantify the extinction rate which is estimated to be significantly larger than zero for these birds.

The methods can easily be applied to other phylogenies using the R package TreePar available on CRAN.