Divergence Times of Eutherian Mammals

In the continuing debate about the timing of the origin of major extant placental clades, both proponents of a divergence after the Cretaceous-Tertiary (K-T) boundary and those advocating divergence deep within the Cretaceous too often miss what the Late Cretaceous record of placentals actually shows. For example, Foote et al. (1) are correct that many Late Cretaceous reports of extant ordinal and superordinal placental taxa are now questioned (2). They are incorrect, however in extending this statement to all such taxa, notably the “zhelestids. ” Foote et al. essentially dismiss “zhelestids ” as being “archaic eutherians allied with either Prokennalestes