Forensic speciation: Splicing genetic and phylogenic trees of life
(Phys.org)—The Tree of Life is a beautiful and elegant metaphor that has proven deceptively difficult to reconstruct. The main culprit may be the overwhelming reliance on so-called concatenation methods, which combine different genes into a single matrix and so force all genes to conform to the same topology. Since these methods do not take into account differences between alternative gene trees, they have been thought to lead to uncertainty or incongruence in the phylogenic tree of the eutherian (placental) mammals. While historically this incongruence had not previously been confirmed by empirical studies, scientists at Shenyang Normal University, Tsinghua University, University of Georgia and Harvard University have recently demonstrated that this is indeed the case – and that concatenation-derived uncertainty may be found in other clades (biological groups derived from a common ancestor) as well. Moreover, the authors suggest that such uncertainty can be resolved by augmenting phylogenomic data with coalescent...