Aiello, L. C. & Wheeler, P. (1995) The expensive-tissue hypothesis: The brain and the digestive system in human and primate evolution. Current Anthropology
Bering, J. (2010) The God instinct. Nicholas Brealey.
Dennett, D. (1995) Darwin's dangerous idea. Simon & Schuster.
Geary, D. C. (2005) The origin of mind. American Psychological Association.
Nowak, M. A. & Sigmund, K. (1998) Evolution of indirect reciprocity by image scoring. Nature
Oda, R., Niwa, Y., Honma, A. & Hiraishi, K. (2011) An eye-like painting enhances the expectation of a good reputation. Evolution and Human Behavior
Pinker, S. (1997) How the mind works. Norton.
Premack, D. & Woodruff, G. (1978) Does the chimpanzee have a theory of mind?
Behavioral and Brain Sciences
Shermer, M. (2011) The believing brain. Times Books.
Tinbergen, N. (1963) On aims and methods of ethology. Zeitschrift für Tierpsychologie