Resolution of the early placental mammal radiation using Bayesian phylogenetics

A 16,397-base-pair dataset of 19 nuclear and 3 mitochondrial genes from 42 placentals and 2 marsupial outgroups recovered Afrotheria, Xenarthra, Laurasiatheria and Euarchontoglires and an Afrotheria-rooted topology under Bayesian and maximum-likelihood analyses; the root, approximately 103 Ma date and Gondwanan scenario remain model-conditioned.

The 100–0 Ma Placentalia route is a model envelope: a molecular analysis estimated a roughly 103 Ma deep placental split, whereas the phenomic combined analysis placed sampled crown diversification after K–Pg; neither model is a fossil FAD or ancestor observation.

A 16,397-base-pair placental matrix recovers Afrotheria in its sampled topology and estimates an approximately 103 Ma split under its models; the atlas’s 100 Ma navigation ceiling is rounded model context, not a fossil occurrence, exact crown origin or African ancestor location.