CAREER:Comparative Osteohistology: Exploring Microstructural Signatures of Environmental Stress in Modern and Fossil Ecosystems

Macalester College, Saint Paul MN

Investigators

Abstract

Bone tissue is commonly used to reconstruct life histories of fossil vertebrates, but our understanding of bone histology is limited by a lack of baseline data that test the relationships between bone microstructure and biology in living animals. In order to clarify the relationships between bone microstructure and the controlling parameters of phylogeny and environment, I propose a study that documents histological variation (1) within single skeletons; (2) among vertebrate taxa; and (3) across distinctive habitats. Drought assemblages are the focal point of the study for several reasons. First, modern systems indicate that drought and its attendant hardships leave a signature in vertebrate hard tissues. Moreover, there is strong evidence that drought generates bonebeds in the vertebrate fossil record that constitute the archive of life history variation in ancient populations. The PI will first compare the bone tissue of vertebrates inhabiting the drought-prone ecosystem of Hwange National Park in Zimbabwe with a sample of vertebrates derived from captivity and held in museum collections. Secondly, she will pursue similar questions and methods as she investigates fossil vertebrate assemblages from similar environmental contexts in the Late Cretaceous of Montana and Madagascar. This research takes the first necessary step toward ground-truthing the bone histological signals across vertebrate groups, environments, and time, and will provide a baseline appreciation of bone histological responses to ecological stress among taxonomic groups, body sizes, and even within single skeletons. Ultimately, this study will have far-reaching implications for paleobiologists and neontologists who use bone tissue to explore both modern and ancient biological systems. The research component of this project is tightly integrated with an educational outreach component that: 1) incorporates the research into courses she teaches, including development of a new course that focuses specifically on data collection and analysis in collaboration with Macalester College undergraduates; 2) initiates domestic and international research with ~15 undergraduate students over the 5 years of the project; 3) connects 2 undergraduate students per year to academic enrichment programs aimed at under-resourced K-12 minority students in the Minneapolis-St. Paul metro area; and 4) creates K-12 curriculum tied to Minnesota Science Standards through collaboration with undergraduates, public school teachers, and the Bell Museum of Natural History.