geobiology of invertebrates lab

spineless creatures

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

  1. biotic replacement of one group by another in tropical ecosystems
  2. rates, magnitudes and timing of the replacements
  3. 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 also 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 paleoecologic factors that combined to allow the reef ecosystem to persist over 600 million years of Earth’s history. With this knowledge, predictions about the future health of our modern reef ecosystem can be made.

research sites


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.



My research in the Olduvai Gorge basin focuses on paleotropical environmental reconstructions at the time of evolving lineages of homins. Field seasons in Tanzania concentrate on bivalve taxonomy and paleoecology, and on depositional environments for ˜1 million year-old rocks.




Dinosaurs and Their Relatives

The objectives of the lecture and laboratory sessions are to increase your understanding of three major themes: (1) the origin and evolution of vertebrates, including dinosaurs and their distant relatives the fish, amphibians and amniotes, and their recent relatives the birds; (2) geography and climate of the Earth during the evolution of these groups but especially during the time of the dinosaurs and birds; and (3) dinosaur morphology, phylogeny, evolution, paleobiology, paleoecology, and extinction.



The Natural History of Coral Reefs

The course will address the evolutionary history of reef ecosystems through geologic time inclusive of reef composition and global distribution, modern reef development, conservation and management practices, and the persistence of the reef ecosystem through climate change scenarios. We will cover biologic, ecologic, and geologic principles as they pertain to coral reef ecosystems.



Invertebrate Paleontology

Application of biological principles and use of invertebrate fossils in the study of Earth’s history; origin of life and the early fossil record; evolution; approaches of taxonomy; chemistry of fossils; ecology of ancient life; use of fossils to measure geologic time. To gain an appreciation of the theoretical framework for these evolutionary and extinction events. Through lectures, discussions, assigned readings, exercises, and an abundance of analyses with invertebrate fossils, you will be exposed to numerous aspects of paleontology.


contact information

dr. claudia c. johnson
department of earth and atmospheric sciences
indiana university
1001 e. 10th st. bloomington in 47405

phone: 812-855-0646