Technical comment on "The placental mammal ancestor and the post-K-Pg radiation of placentals".
O'Leary et al. (Research Article, 8 February 2013, p. 662) examined mammalian relationships and divergence times and concluded that a single placental ancestor crossed the Cretaceous-Paleogene (K-Pg) boundary. This conclusion relies on phylogenetic analyses that fail to discriminate between homology and homoplasy and further implies virus-like rates of nucleotide substitution in early Paleocene placentals.
Department of Biology, University of California, Riverside, CA 92521, USA. mark.springer@ucr.edu
Mark S
MS
Springer
Robert W
RW
Meredith
Emma C
EC
Teeling
William J
WJ
Murphy
D000818:Animals; D005075:Biological Evolution; D005260:Female; D005580:Fossils; D008322:Mammals; D010802:Phylogeny; D011247:Pregnancy