Speaking this week will be Xia Hua from the Mathematical Sciences Institute, here at ANU!

Title: Modelling Speciation Processes On Phylogeny

Abstract:

What are the speciation processes that generated a species group? The answer to this question lies in genetic difference not only among species, but also among lineages within each species. With the advance of genome sequencing in non-model organisms and the statistical tools to improve accuracy in inferring evolutionary histories among recently diverged lineages, we now have the lineage-level trees to answer these questions. What is needed is a phylogenetic approach to model different types and rates of speciation processes that generates both the trees and species identities of extant lineages. The approach needs to account for both the initiation and the completion of a speciation process and allow calculation of the probability that certain lineages belong to certain species and have an evolutionary history consistent with the tree under different models of speciation processes. Here we propose such an approach and test its performance on both simulated data and real dat!

 a. We show that maximum likelihood estimates of the speciation processes are accurate, give reasonable estimates from real data, and is able to test speciation theories that explicitly link molecular substitutions and speciation.