About the Authors

Jeffrey W. Martz

typothorax@gmail.com

Affiliation Division of Resource Management, Petrified Forest National Park, Petrified Forest, Arizona, United States of America

William G. Parker

Affiliation Division of Resource Management, Petrified Forest National Park, Petrified Forest, Arizona, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: JWM. Performed the experiments: JWM WGP. Analyzed the data: JWM WGP. Wrote the paper: JWM.