Christine Janis is Professor of Biology in the Department of Ecology and Evolutionary Biology at Brown University. She is on the editorial board of Journal of Mammalian Evolution and Acta Paleontologica Polonica, Associate Editor for the journal Evolution. Professor Janis was also editor-in-chief for Evolution of Tertiary Mammals of North America Volume 1: Terrestrial Carnivores, Ungulates, and Ungulate like Mammals (Cambridge University Press 1998).

Gregg Gunnell is Associate Research Scientist in the Museum of Paleontology at the University of Michigan. He is Associate Editor for the journal Palaois, Past Associate Editor for Journal of Human Evolution, and a Member of the Society for Vertebrate Paleontology, the Paleontological Society, and the American Society of Mammalogists.

Mark Uhen is Head of Research and Collections and Curator of Paleontology and Zoology at the Cranbrook Institute of Science. He is a Research Associate in the Department of Paleobiology at the US National Museum of Natural History, Chair of the Society of Vertebrate Paleontology Patterson Award Committee, and a member of the Advisory Board and the Vertebrate Working Group for the Paleobiology Database.

This second volume completes the unique survey of North American Tertiary mammals, and covers all the remaining taxa not contained in Volume 1. It provides a complete listing of mammalian diversity over time and space, and evaluates the effect of biogeography and climatic change on evolutionary patterns and faunal transitions, with the distribution in time and space of each taxon laid out in a standardized format. It contains six summary chapters that integrate systematic and biogeographic information for higher taxa, and provides a detailed account of the patterns of occurrence for different species at hundreds of different fossil localities, with the inclusion of many more localities than were contained in the first volume. With over thirty chapters, each written by leading authorities, and an addendum that updates the occurrence and systematics of all of the groups covered in Volume 1, this will be a valuable reference for paleontologists and zoologists.