- Received November 27, 2015.
- Accepted December 10, 2015.
- Published online January 20, 2016.
Copyright & Usage
© 2016 The Authors. Published by the Royal Society under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the original author and source are credited.
- 1Faculty of Social Sciences and Humanities, Institute for the Study of Literature and Tradition, New University of Lisbon, Avenida de Berna, 26-C, Lisboa 1069-061, Portugal
- 2Department of Anthropology and Centre for the Coevolution of Biology and Culture, Durham University, Durham DH1 1LE, UK