Claudia C. Johnson

A primary focus of my research is to evaluate evolutionary processes in the paleotropics. My research initiatives address:

• biotic replacement of one group by another in tropical ecosystems
• rates, magnitudes and timing of the replacements
• tropical environmental processes

The reef ecosystem provides the empirical database from which I synthesize patterns and processes affecting reef evolution and demise. I examine reefs that evolved under Cretaceous "greenhouse", Pleistocene "icehouse" and Oligocene transitional climate states, and evaluate biotic changes in the context of the tropical ocean-climate system. I have an active program examining modern reefs to ascertain if a biotic replacement will occur as we move rapidly toward a warmer climate state. The ultimate focus of my work is to evaluate the complexity of paleobiologic and ecologic factors that combined to allow the reef ecosystem to persist over 600 million years of Earths history. With this knowledge, I anticipate predictions about the future health of our modern reef ecosystem can be made.

My research area is focused in the Caribbean region, and my students and I pursue field investigations in Texas, Florida, Puerto Rico, the Dominican Republic and Barbados. We travel to museums such as the National Museum of Natural History, the Paleontological Research Institute, the Museo del Hombre Dominicano, and the Texas Memorial Museum to acquire specific paleontological specimens for research.

An extension of my research to the Olduvai Gorge basin focuses on evaluation of the finer points of paleotropical environmental reconstructions at the time of evolving lineages of hominids. 2013 and 2014 field seasons in Tanzania concentrated on ~1 million year-old bivalve taxonomy and systematics and depositional environments. Sequence stratigraphic analyses will allow for further interpretations of the evolving paleoenvironments.

As distinguished lecturer for the Paleontological Society, I've presented research results to 17 institutions in three countries across Geology, Biology and Geography departments.

I am the recipient of NSF grants on the subject of ancient ocean-climate systems, and I co-edited two research volumes and numerous papers on the topic. Currently, three Ph.D. students are studying integrated geobiological aspects of the paleoclimate paleocean system. My graduate students receive grants from The Paleontological Society, Sigma Xi, the Geological Society of America and the Latin American Foundation, as well as private and federal agencies.

The IU Paleontology Collection is under the umbrella of the Center for Biological Research Collections. The 5th floor of the Geology Building houses a fossil specimen repository with over 1.25 million specimens, as well as teaching and research collections. We house extensive fossil collections from Indiana and beyond, and our students work on the collections routinely as part of their academic education.

Claudia C. Johnson named Herman B. Wells Endowed Professor