About the Authors
- Alan Cross, Mark Collard
- Laboratory of Human Evolutionary Studies, Department of Archaeology, Simon Fraser University, Burnaby, British Columbia, Canada
- Andrew Nelson
- Department of Anthropology, University of Western Ontario, London, Canada
The authors have declared that no competing interests exist.
Conceived and designed the experiments: AC. Performed the experiments: AC. Analyzed the data: AC MC AN. Contributed reagents/materials/analysis tools: AC. Wrote the paper: AC MC AN.