Impacts of the Cretaceous Terrestrial Revolution and KPg Extinction on Mammal Diversification

1. Robert W. Meredith¹,*,
2. Jan E. Janecka²,*,
3. John Gatesy¹,
4. Oliver A. Ryder³,
5. Colleen A. Fisher²,
6. Emma C. Teeling⁴,
7. Alisha Goodbla⁴,
8. Eduardo Eizirik⁵,
9. Taiz L. L. Simão⁵,
10. Tanja Stadler⁶,
11. Daniel L. Rabosky⁷,
12. Rodney L. Honeycutt⁸,
13. John J. Flynn⁹,¹⁰,
14. Colleen M. Ingram⁹,
15. Cynthia Steiner³,
16. Tiffani L. Williams¹¹,
17. Terence J. Robinson¹²,
18. Angela Burk-Herrick¹,¹³,
19. Michael Westerman¹⁴,
20. Nadia A. Ayoub¹,¹⁵,
21. Mark S. Springer¹,*†,
22. William J. Murphy²,*†

+ Author Affiliations

1. ¹Department of Biology, University of California, Riverside, CA 92521, USA.
2. ²Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77843, USA.
3. ³San Diego Zoo's Institute for Conservation Research, Escondido, CA 92027, USA.
4. ⁴UCD School of Biology and Environmental Science, University College Dublin, Belfield, Dublin 4, Ireland.
5. ⁵Faculdade de Biociências, PUCRS, Porto Alegre, RS 90619–900, Brazil.
6. ⁶Institut für Integrative Biologie, Eidgenössiche Technische Hochschule Zurich, 8092 Zurich, Switzerland.
7. ⁷Department of Integrative Biology, University of California, Berkeley, CA 94720, USA.
8. ⁸Division of Natural Science, Pepperdine University, Malibu, CA 90263, USA.
9. ⁹Division of Paleontology and Sackler Institute of Comparative Genomics, American Museum of Natural History, New York, NY 10024, USA.
10. ¹⁰Richard Glider Graduate School, American Museum of Natural History, New York, NY 10024, USA.
11. ¹¹Department of Computer Science, Texas A&M University, College Station, TX 77843, USA.
12. ¹²Department of Botany and Zoology, University of Stellenbosch, Matieland 7602, South Africa.
13. ¹³Chaffey College, Rancho Cucamonga, CA 91737, USA.
14. ¹⁴Genetics Department, LaTrobe University, Bundoora, Victoria 3086, Australia.
15. ¹⁵Department of Biology, Washington and Lee University, Lexington, VA 24450, USA.

1. †To whom correspondence should be addressed. E-mail: mark.springer@ucr.edu (M.S.S.); wmurphy@cvm.tamu.edu (W.J.M.)

Abstract

Previous analyses of relations, divergence times, and diversification patterns among extant mammalian families have relied on supertree methods and local molecular clocks. We constructed a molecular supermatrix for mammalian families and analyzed these data with likelihood-based methods and relaxed molecular clocks. Phylogenetic analyses resulted in a robust phylogeny with better resolution than phylogenies from supertree methods. Relaxed clock analyses support the long-fuse model of diversification and highlight the importance of including multiple fossil calibrations that are spread across the tree. Molecular timetrees and diversification analyses suggest important roles for the Cretaceous Terrestrial Revolution and Cretaceous-Paleogene mass extinction in opening up ecospace that promoted interordinal and intraordinal diversification, respectively. By contrast, diversification analyses provide no support for the Eocene delayed rise of present-day mammals hypothesis.