The Placental Mammal Ancestor and the Post–K-Pg Radiation of Placentals

@article{OLeary2013ThePM,
  title={The Placental Mammal Ancestor and the Post–K-Pg Radiation of Placentals},
  author={Maureen A O'Leary and Jonathan I. Bloch and John J. Flynn and Timothy J. Gaudin and Andres Giallombardo and Norberto P. Giannini and Suzann L. Goldberg and Brian P. Kraatz and Zhe-Xi Luo and Jin Meng and Xijun Ni and Michael J. Novacek and Fernando Araujo Perini and Zachary S Randall and Guillermo W Rougier and Eric J. Sargis and Mary T. Silcox and Nancy B. Simmons and Michelle Spaulding and Pa{\'u}l M. Velazco and Marcelo Weksler and John R. Wible and Andrea L. Cirranello},
  journal={Science},
  year={2013},
  volume={339},
  pages={662 - 667}
}
Let There Be Mammals The timing of the evolution and radiation of placental mammals and their most recent common ancestor has long been debated, with many questions surrounding the relationships of groups that pre- and postdate the Cretaceous-Paleogene boundary (66 million years ago). While the fossil record suggests that placental mammals radiated after the Cretaceous, molecular clocks have consistently placed the ancestors of mammalian lineages earlier. O'Leary et al. (p. 662; see the… Expand
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