De Smedt, Johan, and Helen De Cruz. “Human Artistic Behaviour: Adaptation, Byproduct, or Cultural Group Selection?” Philosophy of Behavioral Biology, edited by Kathryn S Plaisance and Thomas AC Reydon, vol. 282 (4), Springer, 2012, pp. 167–87, doi:10.1007/978-94-007-1951-4_8.