Peer-reviewed
The placental mammal ancestor and the post-K-Pg radiation of placentals
Maureen A O'Leary, Jonathan I Bloch, John J Flynn, Timothy J Gaudin, Andres Giallombardo, Norberto P Giannini, Suzann L Goldberg, Brian P Kraatz, Zhe-Xi Luo, Jin Meng, Xijun Ni, Michael J Novacek, Fernando A Perini, Zachary S Randall, Guillermo W Rougier, Eric J Sargis, Mary T Silcox, Nancy B Simmons, Michelle Spaulding, Paúl M Velazco, Marcelo Weksler, John R Wible, Andrea L Cirranello
To discover interordinal relationships of living and fossil placental mammals and the time of origin of placentals relative to the Cretaceous-Paleogene (K-Pg) boundary, we scored 4541 phenomic characters de novo for 86 fossil and living species. Combining these data with molecular sequences, we obtained a phylogenetic tree that, when calibrated with fossils, shows that crown clade Placentalia and placental orders originated after the K-Pg boundary. Many nodes discovered using molecular data are upheld, but phenomic signals overturn molecular signals to show Sundatheria (Dermoptera + Scandentia) as the sister taxon of Primates, a close link between Proboscidea (elephants) and Sirenia (sea cows), and the monophyly of echolocating Chiroptera (bats). Our tree suggests that Placentalia first split into Xenarthra and Epitheria; extinct New World species are the oldest members of Afrotheria
Article, 2013