Alexander, Richard D.1987. The Biology of Moral Systems. Hawthorne , N.Y. : Aldine deGruyter.

Almond, Gabriel A., R. ScottAppleby, and EmmanuelSivan. 2003. Strong Religion: The Rise of Fundamentalism around the World. Chicago : Univ. of Chicago Press.

Bowles, Sam, and HerbertGintis. 2002. “The evolution of strong altruism  .”Discussion paper, Univ. of Massachusetts at Amherst.

Boyd, Robert, and Peter J.Richerson. 1992. “Punishment Allows the Evolution of Cooperation (or Anything Else) in Sizable Groups. Ethology and Sociobiology  13 (3): 171–96.

Boyd, Robert, and Peter J.Richerson2001. “The Evolution of Subjective Commitment to Groups: A Tribal Instinct Hypothesis  .”In Evolution and the Capacity for Commitment, ed. R.Nesse, 186–220. New York : Russell Sage Foundation.

Conrad, Joseph1923. The Secret Agent. New York : Doubleday.

CronkL1994. “Evolutionary Theories of Morality and the Manipulative Use of Signals. Zygon: Journal of Religion and Science  29 (March): 81–101.

Dawkins, Richard. 1989. The Selfish Gene. Rev. ed. Oxford : Oxford Univ. Press.

Dunbar, Robin I. M.1996. Grooming, Gossip, and the Evolution of Language. Cambridge : Harvard Univ. Press.

Earle, Timothy. 1997. How Chiefs Come to Power: The Political Economy in Prehistory. Stanford : Stanford Univ. Press.

Fehr, Ernst, and SimonGächter. 2000. “Altruistic Punishment in Humans. Nature  415: 137–40.

Frank, Robert. 1988. Passions within Reason. New York : W. W. Norton.

Gintis, Herbert. 2000. “Strong Reciprocity and Human Sociality. Journal of Theoretical Biology  206: 169–79.DOI: 10.1006/jtbi.2000.2111

Hefner, Philip. 1993. The Human Factor: Evolution, Culture, and Religion. Minneapolis : Fortress.

Hirschleifer, Jack. 1987. “The Emotions as Guarantors of Threats and Promises  .”In The Latest on the Best: Essays on Evolution and Optimality, ed. JohnDupre, 307–26. Cambridge : MIT Press.

Iannaccone, L. R.1992. “Sacrifice and Stigma: Reducing Free‐Riding in Cults, Communes, and other Collectives. Journal of Political Economy  100: 271–91.DOI: 10.1086/261818

Irons, William. 1996. “In Our Own Self Image: The Evolution of Morality, Deception, and Religion. Skeptic  4 (2): 50–61.

Irons, William. 2001a. “Why Are Humans Religious? An Inquiry into the Evolutionary Origin of Religion. Currents in Theology and Mission  28: 3–4 (June/August 2001): 357–68.

Irons, William. 2001b. “Religion as a Hard‐to‐Fake Sign of Commitment  .”In Evolution and the Capacity for Commitment, ed. R. M.Nesse, 292–309. New York : Russell Sage Foundation.

Johnson, Allen W., and TimothyEarle. 2000. The Evolution of Human Societies: From Foraging Group to Agrarian State. Second ed. Stanford : Stanford Univ. Press.

Lomborg, Bjørn. 2001. The Skeptical Environmentalist: Measuring the Real State of the World. Cambridge : Cambridge Univ. Press.

Maynard Smith, John, and DavidHarper. 2003. Animal Signals. Oxford : Oxford Univ. Press.

Nesse, Randolph M., ed 2001a. Evolution and the Capacity for Commitment. New York : Russell Sage Foundation.

Nesse, Randolph M., ed 2001b. “Natural Selection and the Capacity for Subjective Commitment  .”In Evolution and the Capacity for Commitment, ed. R. M.Nesse, 1–44. New York : Russell Sage Foundation.

Nowak, Martin A., and KarlSigmund. 1998. “Evolution of Indirect Reciprocity by Imaging Scoring. Nature  394 (6685): 573–77.

Ostrom, Elinor. 1990. Governing the Commons: The Evolution of Institutions for Collective Action. Cambridge : Cambridge Univ. Press.

Patton, John Q.2000. “Reciprocal Altruism and Warfare: A Case from the Ecuadorian Amazon  .”In Adaptation and Human Behavior: An Anthropological Perspective, ed. L.Cronk, N.Chagnon, and W.Irons, 417–36. Hawthorne , N.Y. : Aldine de Gruyter.

Patton, John Q.2003. “Warfare, Status, and Collective Action in the Ecuadorian Amazon: Is Free‐Riding Really a Problem?” Paper given at the 2003 annual meeting of the American Anthropological Association  , Chicago , Illinois .

Ridley, Matt. 1996. The Origin of Virtue: Human Instincts and the Evolution of Cooperation. New York : Viking.

Schelling, Thomas C.1960. The Strategy of Conflict. Cambridge : Harvard Univ. Press.

Schelling, Thomas C.2001. “Commitment: Deliberate Versus Involuntary  .”In Evolution and the Capacity for Commitment, ed. R. M.Nesse, 48–56. New York : Russell Sage Foundation.

Sosis, Richard. 2000. “Religion and Intra‐Group Cooperation: Preliminary Results of a Comparative Analysis of Utopian Communities. Cross-Cultural Research  34: 70–87.

Sosis, Richard. 2003. “Why Aren't We All Hutterites? Costly Signaling Theory and Religious Behavior. Human Nature  14: 91–127.

Sosis, Richard, and CandaceAlcorta. 2003. “Signaling, Solidarity, and the Sacred: The Evolution of Religious Behavior. Evolutionary Anthropology  12: 264–74.

Sosis, Richard, and EricBressler. 2003. “Cooperation and Commune Longevity: A Test of the Costly Signaling Theory of Religion. Cross-Cultural Research  37: 211–39.

Sosis, Richard, and Bradley J.Ruffle. 2003. “Religious Ritual and Cooperation: Testing for a Relationship on Israeli Religious and Secular Kibbutzim. Current Anthropology  44: 713–22.

Williams, George C.1966. Adaptation and Natural Selection. Princeton : Princeton Univ. Press.

Wilson, David Sloan. 2002. Darwin's Cathedral: Evolution, Religion, and the Nature of Society. Chicago : Univ. of Chicago Press.

Wright, Robert. 2000. Nonzero: The Logic of Human Destiny. New York : Vintage Books.

Zahavi, Amotz. 1975. “Mate Selection‐A Selection for a Handicap. Journal of Theoretical Biology  53: 205–14.