Matthew W. Hahn, Indiana University

Dealing with discordance in the Tree of Life

Phylogenetics is concerned with uncovering the relationships among organisms (the “Tree of Life”), and statistical computational research has made many important contributions to achieving this goal. In this talk I discuss a major overall challenge facing the field as DNA sequencing efforts have become central to this work: many individual genes have tree topologies that do not match the tree describing relationships among species. Such gene-tree discordance poses many new difficulties for inferring the Tree of Life. Here, I present three approaches for dealing with discordance: 1) an ILS-aware method for counting gene duplications and losses; 2) a quartet summary approach that combines many different gene-tree topologies to construct an accurate species tree, even in the presence of duplication and loss; and 3) a probabilistic approach to reconstructing the history of different traits on a species tree in the presence of discordance. These three problems (and their solutions) represent just a fraction of the challenges now facing the field of phylogenetics.

Weitere Infos zur Veranstaltung