About the Authors

Andrew T. McDonald

atmcdonald28@gmail.com

Affiliation Earth Sciences, Saint Louis Science Center, Saint Louis, Missouri, United States of America

Carl E. Campbell

Affiliation Geology, St. Louis Community College-Meramec, Saint Louis, Missouri, United States of America

Brian Thomas

Affiliation Earth Sciences, Saint Louis Science Center, Saint Louis, Missouri, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: ATM CEC BT. Performed the experiments: ATM CEC BT. Analyzed the data: ATM CEC BT. Contributed reagents/materials/analysis tools: ATM CEC BT. Wrote the paper: ATM CEC.