Alcock, John. 2013. Animal Behavior: An Evolutionary Approach. 10th ed. Sunderland, Mass: Sinauer Associates.
Begon, Michael, Colin R. Townsend, John L. Harper, and John L. Harper. 2006. Ecology: From Individuals to Ecosystems. 4th ed. Malden, Mass: Blackwell.
Dawkins, Richard. 2006. The Selfish Gene. 30th anniversary ed. Oxford: Oxford University Press.
Zimmer, Carl. 2014. The Tangled Bank: An Introduction to Evolution. Second edition. Greenwood Village, Colorado: Roberts and Company.