PAUL L. KOCH Professor of Earth & Planetary Sciences Department Chair Isotope Biogeochemistry and Vertebrate Paleontology
		Office: EMS A250 Phone: 831-459-5861 Fax: 831-459-3074 E-mail: pkoch@es.ucsc.edu Lab: D206, x9-5088		For more information: • Publications • Website

Education and Training

B.A., University of Rochester
M.S., Ph.D., University of Michigan

Research Interests

Paul's research focuses on vertebrate paleoecology and evolution. He places his studies of vertebrates in environmental context through reconstruction of ancient ecosystems and climates. His work often includes biogeochemical analysis of animal tissues (teeth, bones, fur, skin, etc.) or environmental samples (soil minerals, fossil plants, etc.).

In recent years, Paul has continued his work on Cenozoic environmental evolution. He has done a great deal of work on the chronology and ecological consequences of the Paleocene-Eocene boundary thermal maximim (PETM) and other less pronounced climatic events in the early Cenozoic. Since 2000, much ofthis work has been in Asia, where he and his colleagues have shown that the first appearance of many "modern" orders of mammals (e.g., primates, perrisodacyls) is essentially coincident with the PETM, as is the case on other northern continents. With former post-doc David Fox, he studied the origin of the prairie ecosystem in North America. With past and current graduate students, he has begun to explore the topographic history of the western United States using a variety of different isotopic tools. Finally, with graduate students and other colleagues, he is reconstructing Holocene oceanographic changes along the California coast through biogeochemical records retrieved from mollusk shells.

Another major focus has been detailed reconstruction of the paleoecology of different groups of vertebrates. He and his students have studied the diets, habitat preferences, and migratory behaviors of many taxa. In some cases, they've focused on evolutionary ecology, for example investigating the stages in the transition from terrestrial to aquatic habitats in cetaceans (dophins, whales, and their kin) and sirenians (manatees, sea cows, etc.). Another example is their ongoing work on the evolution of salt-water tolerance in crocodilians. In other cases, they've worked at an ecosystem scale, exploring how different members of a community exploit food resources or space. Much of this latter work has focused on Pleistocene communities. They've studied diet breadth or habitat preferences in many taxa (teratorns, dire wolves, horses, hippos, proboscideans, bison, mole rats, etc.) and the migratory patterns of mammoths and mastodons. Paul's original motivation was to study the ecology of these systems to understand the factors leading to the late Pleistocene extinction of many of these species, but in recent years, he's focused more on how these ancient communities "worked" prior to their restructuring by this extinction. An important related thread has been reconstruction of the prior ecological roles of extant, endangered species through study of their Pleistocene or Holocene fossils. He and his students have a number of ongoing projects on seals and sea lions, lemurs, condors, and wolves. In some cases, their work has shown that species behaved very differently in the recent past. They've tried to understand why behaviors have changed, and whether or not species might be able to "recover" their lost ecological potential.

Finally, a great deal of work in Paul's lab is now devoted to ecological studies of modern animals. In some cases, these studies are designed as "ground-truthing" excercises to set the stage for paleoecological studies. In a growing number of cases, however, there are no "paleo" connections. Rather, ecologists studying modern species have discovered that the biogeochemical methods developed to study ancient animals can provide insights into the ecology of living species, especially ones with behaviors or habitats that make them hard to observe or track (e.g., migratory birds, marine mammals, deep forest species). Beginning with Paul's early work on the ecology of living elephants, this work has expanded greatly (especially in the work of his graduate students) to include African carnivores, lemurs, sharks, and many different kinds of seals and sea lions.

Teaching Interests

Natural History of Dinosaurs, History of Life, Isotopes in Ecology and Paleoecology, Paleontology Seminar