OEB Seminar Series: Liam Revell

Liam Revell 
Professor of Biology 
University of Massachusetts, Boston

Unlocking a flexible set of new models for discrete & continuous trait evolution in phylogenetic comparative biology

Abstract: The practical utility of many modern phylogenetic comparative methods can depend on how accurately mathematical models capture the evolutionary process of traits. In a nearly decade-old paper, Boucher and Démery (2016) identified an interesting utility of the equivalence of an equal-rates, symmetric, ordered Markov chain and continuous stochastic diffusion (in the limit as the number of steps in our chain goes to ∞) for fitting a model with no tractable analytic likelihood function -- in their case, Brownian motion with reflecting boundaries. Professor Revell refers to this equivalence as the discretized diffusion approximation. He subsequently realized that this approximation could help unlock a number of other new or intractable models in the phylogenetic comparative analysis of discrete and continuous trait data, some of which he will explore in this presentation.

Host: Professor Cavender-Bares