Distinguishability in Genealogical Phylogenetic Networks

Description and Aim

The traditional model for representing evolution is the phylogenetic tree, which provides an adequate model for capturing mutation and speciation/duplication events, which are the important components of biological diversification. However, it is less suited to capturing common “reticulate” evolutionary phenomena, such as hybridization, recombination or lateral gene transfer, i.e. events in which lineages combine, rather than diversify. That is, we need to distinguish both the horizontal and vertical components of evolutionary descent, and only networks can do this.

There is growing interest in developing algorithms for reconstructing genealogical phylogenetic networks from biological, linguistic and other data. However, the computational aspect of reconstructing such networks has proven to be significantly more difficult than reconstructing phylogenetic trees.

Two previous Lorentz workshops in 2012 and 2014 have had as their long-term goals the development of practical algorithms for phylogenetic networks, and directing mathematical research on this topic in the directions that are most relevant for biologists.

The current workshop focusses on indistinguishability issues that significantly complicate the reconstruction, analysis and interpretation of phylogenetic networks. We will discuss mathematical, computational, biological and linguistic components of a number of topics, including: (i) distinguishing horizontal from vertical descent, (ii) distinguishing reticulate processes, (iii) distinguishing reticulate evolution from incomplete lineage sorting, (iv) distinguishing network topologies, and (v) integrating reconstruction methods.