About the Authors

Donald M. Henderson

don.henderson@gov.ab.ca

Affiliation Royal Tyrrell Museum of Palaeontology, Drumheller, Alberta, Canada

Competing Interests

The author has declared that no competing interests exist.

Author Contributions

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