An Analytical Comparison of Multilocus Methods Under the Multispecies Coalescent: The Three-Taxon Case

Incomplete lineage sorting (ILS) is a common source of gene tree incongruence in multilocus analyses. Numerous approaches have been developed to infer species trees in the presence of ILS. Here we provide a mathematical analysis of several coalescent-based methods. The analysis is performed on a three-taxon species tree and assumes that the gene trees are correctly reconstructed along with their branch lengths. It suggests that maximum likelihood (and some equivalents) can be significantly more accurate in this setting than other methods, especially as ILS gets more pronounced.