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5Wrangham, Richard W., Catching Fire: How Cooking Made Us Human (New York: Basic Books, 2009), p. 106.
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19Thayer, 2004; Rosen, 2004.
20Wilson, Edward O., Consilience: The Unity of Knowledge (London: Abacus, 1999).
22Thucydides, History of the Peloponnesian War, Rex Warner, trans. (Harmondsworth, UK: Penguin 1954), Book 1, Chapter 23.
23Morgenthau, Hans J., Politics Among Nations (New York: Alfred Knopf, 1956).
24Morgenthau, Hans J., Scientific Man Versus Power Politics (Chicago: University of Chicago Press, 1946).
25Waltz, Kenneth N., Theory of International Politics (New York: McGraw-Hill, 1979), pp. 114–116.
26Waltz, Kenneth N., “The stability of a bipolar world,” Daedalus, 1964, 93(3): 881–909.
27Waltz, 1979, pp. 73–74, 77–101.
28Waltz, 1979, pp. 161–193.
29Mearsheimer, 2001, pp. 338–344.
30Waltz, 1979, Chapter 8.
31Mearsheimer, 2001, pp. 1–8.
32Mearsheimer, 2001, p. 21.
33For an analysis of offensive realism and defensive realism, see Lynn-Jones, Sean M., “Realism and America’s rise: A review essay,” International Security, 1998, 23(2): 157–182.
34An exceptional study of realism, and in some respects the fountainhead of offensive realism is Ashley Joachim Tellis, The Drive to Domination: Towards a Pure Realist Theory of Politics, Ph.D. dissertation (Chicago: University of Chicago, 1994).
35Mearsheimer, John J., “The false promise of international institutions,” International Security, 1994–1995, 19(3): 5–49.
36Mearsheimer, 2001, pp. 1–5.
38Labs, p. 12.
39Mearsheimer, 2001, p. 30–31.
40Mearsheimer, 2001, p. 32.
41Chagnon, Napoleon, Noble Savages: My Life Among Two Dangerous Tribes—The Yanomamo and the Anthropologists (NY: Simon and Schuster, 2014), p. 8.
43Keohane, Robert O., Neorealism and Its Critics (New York: Columbia University Press, 1986a).
44Jervis, Robert, “Cooperation under the security dilemma,” World Politics, 1978, 30(2): 167–174.
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47Onuf, Nicholas Greenwood, World of Our Making: Rules and Rule in Social Theory and International Relations (Columbia: University of South Carolina Press, 1989).
48Barkow et al.
49Buss, David M., ed., The Handbook of Evolutionary Psychology (New York: Wiley, 2005).
50Mirazón Lahr, M., Rivera, F., Power, R. K., Mounier, A., Copsey, B., Crivellaro, F., Edung, J. E., Maillo Fernandez, J. M., Kiarie, C., Lawrence, J., Leakey, A., Mbua, E., Miller, H., Muigai, A., Mukhongo, D. M., Van Baelen, A., Wood, R., Schwenninger, J. L., Grün, R., Achyuthan, H., Wilshaw, A., and Foley, R. A., “Inter-group violence among early Holocene hunter-gatherers of West Turkana, Kenya,” Nature, 2016, 529: 394–398.
51Neumann, Iver B., “International relations as a social science,” Millennium: Journal of International Studies, 2014, 43(1): 330–350.
52Johnson, Dominic D. P., “Survival of the disciplines: Is international relations fit for the new millennium?,” Millennium: Journal of International Studies, 2015, 43(2): 749–763.
53Hobbes, Thomas, “Part 1: Of man,” in Leviathan (Cambridge: Cambridge University Press, 1991 ), pp. 1–115.
54Fowler, James H. and Schreiber, Darren, “Biology, politics, and the emerging science of human nature,” Science, 2008, 322(5903): 912–914.
55Barkow, et al.
56Hodgson and Knudsen.
57Alford and Hibbing.
58Allen, Mark W. and Jones, Terry L., eds., Violence and Warfare among Hunter-Gatherers (Walnut Creek, CA: Left Coast Press, 2014), p. 362.
59Gat 2006 and Azar Gat, “So why do people fight? Evolutionary theory and the causes of war,” European Journal of International Relations, 2009, 15(4): 571–599. For a recent review, see Allen and Jones.
62Low, Bobbi S., “An evolutionary perspective on war,” in Behavior, Culture, and Conflict in World Politics, Zimmerman, William and Jacobson, Harold K., eds. (Ann Arbor: University of Michigan Press, 1993), pp. 13–55.
63Meggitt, Mervyn, Blood Is Their Argument: Warfare Among the Mae Enga Tribesmen of the New Guinea Highland (New York: McGraw-Hill, 1978).
64Keeley, Lawrence H., War Before Civilization: The Myth of the Peaceful Savage (Oxford: Oxford University Press, 1996).
67Guilaine, Jean and Zammit, Jean, The Origins of War: Violence in Prehistory (Oxford: Blackwell, 2004).
68LeBlanc, Steven and Register, Katherine E., Constant Battles: The Myth of the Peaceful, Noble Savage (New York: St. Martin’s Press, 2003).
69Wrangham, Richard W. and Peterson, Dale, Demonic Males: Apes and the Origins of Human Violence (London: Bloomsbury, 1996).
70Allen and Jones.
71Also noting this are Buss, David M. and Shackelford, Todd K., “Human aggression in evolutionary psychological perspective,” Clinical Psychology Review, 1997, 17(6): 605–619.
72John Strate emphasizes the importance of defense from attack by conspecifics, other humans; he argues that it caused the growth of human societies. “The role of war in the evolution of political systems and the functional priority of defense,” Humboldt Journal of Social Relations, 1985, 12: 95–110.
73Wilson, Edward O., On Human Nature (Cambridge, MA: Harvard University Press, 1978), p. 112.
74For an excellent review of the logic for, and evidence of, adaptations for war, see Lopez, Anthony C., “The evolution of war: theory and controversy,” International Theory, 2016, 8(1): 97–139.
75Chagnon, Napoleon A., “Life histories, blood revenge, and warfare in a tribal population,” Science, 1988, 239: 985–992.
79Bowles, Samuel, “Group competition, reproductive leveling, and the evolution of human altruism,” Science, 2006, 314: 1569–1572.
80Wrangham, Richard W. and Glowacki, Luke, “Intergroup aggression in chimpanzees and war in nomadic hunter-gatherers: Evaluating the chimpanzee model,” Human Nature, 2012, 23: 5–29.
81Allen and Jones.
82Wrangham and Glowacki, 2012.
83Wrangham and Glowacki, 2012, p. 19.
85Wrangham, Richard W. and Glowacki, Luke, “Warfare and reproductive success in a tribal population,” Proceedings of the National Academy of Sciences, 2015, 112(2): 348–353.
87Hamilton, William D., “The genetical evolution of social behavior. I,” Journal of Theoretical Biology, 1964a, 7(1): 1–16.
88Hamilton, William D., “The genetical evolution of social behavior. II,” Journal of Theoretical Biology, 1964b, 7(1): 17–52.
89Haldane, J. B. S., “Population genetics,” New Biology, 1955, 18: 34–51.
90Inclusive fitness has recently been the subject of a heated debate in the biological literature; see M. A. Nowak, Corina E. Tarnita, and Edward O. Wilson, “The evolution of eusociality,” Nature, 2010, 466(7310): 1057–1062. However, it is primarily a debate about alternative methods of accounting for genetic fitness, not a criticism of the types of behaviors we expect to see in nature. Both approaches lead to the same conclusions. See David Sloan Wilson, “Clash of paradigms,” Huffington Post, July 15, 2012.
91There is copious evidence from historical and contemporary times that such nepotism is a significant influence in politics. See Betzig, Laura, Despotism and Differential Reproduction: A Darwinian View of History (New York: Aldine, 1986).
92Nowak, Martin A., “Five rules for the evolution of cooperation,” Science, 2006, 314: 1560–1563.
93West, S. A., El Mouden, C., and Gardner, A., “16 common misconceptions about the evolution of cooperation in humans,” Evolution and Human Behavior, 2011, 32: 231–262.
94Frank, Robert H., Choosing the Right Pond: Human Behaviour and the Quest for Status (Oxford: Oxford University Press, 1985), pp. 7–8.
95See, for example, Milinski, Manfred and Parker, Geoffrey A., “Competition for resources,” in Behavioural Ecology: An Evolutionary Approach, Krebs, John R. and Davies, Nick B., eds. (Oxford: Blackwell Scientific Publications, 1991), pp. 137–168.
96Wason, Paul K., The Archaeology of Rank (Cambridge: Cambridge University Press, 2004).
97Mazur, Allan and Booth, Alan, “Testosterone and dominance in men,” Behavioural and Brain Sciences, 1998, 21: 353–397.
99Boehm, Christopher, Hierarchy in the Forest: The Evolution of Egalitarian Behavior (Cambridge, MA: Harvard University Press, 2001).
100Mazur, Allan, Biosociology of Dominance and Deference (Lanham, MD: Rowman and Littlefield, 2005).
102Ludwig, Arnold M., King of the Mountain: The Nature of Political Leadership (Lexington: University Press of Kentucky, 2002).
103King, Andrew J., Johnson, Dominic D. P., and Van Vugt, Mark, “The origins and evolution of leadership,” Current Biology, 2009, 19(19): 1591–1682.
104Lincoln, Gerald A., “Teeth, horns and antlers: The weapons of sex,” in The Differences Between the Sexes, Short, Roger V. and Balaban, Evan, eds. (Cambridge: Cambridge University Press, 1994), pp. 131–158.
105Trivers, Robert L., “Parental investment and sexual selection,” in Sexual Selection and the Descent of Man, Campbell, Bernard, ed. (Chicago: Aldine, 1972), pp. 136–179.
106Lopez, Anthony C., McDermott, Rose, and Petersen, Michael Bang, “States in mind: Evolution, coalitional psychology, and international politics,” International Security, 2011, 36(2): 48–83.
107Ellis, Lee, Hershberger, Scott L., Field, Evelyn M., Wersinger, Scott, Pellis, Sergio, Hetsroni, Amir, and Geary, David et al. , Sex Differences: Summarizing More Than a Century of Scientific Research (New York: Psychology Press, 2008).
108Taylor, Shelley E., Klein, Laura C., Lewis, Brian P., Gruenewald, Tara L., Gurung, Regan A. R., and Updegraff, John A., “Biobehavioral responses to stress in females: Tend-and-befriend, not fight-or-flight,” Psychological Review, 2000, 107: 411–429.
109Van Vugt, Mark and Spisak, Brian R., “Sex differences in leadership emergence during competitions within and between groups,” Psychological Science, 2008, 19(9): 854–858.
111Mazur and Booth.
112McDermott, Rose, “The feeling of rationality: The meaning of neuroscientific advances for political science,” Perspectives on Politics, 2004, 2(4): 691–706.
113Damasio, Antonio R., Descartes’ Error: Emotion, Reason and the Human Brain (New York: Avon, 1994).
115For an excellent general analysis of the genetic origins of aggression and its chemical mediators in humans such as the hormone testosterone, its derivative dihydroxytestosterone (DHT), neurotransmitters such as serotonin, and some of the differences in behavior caused by these factors in men and women, see William R. Clark and Michael Grunstein, Are We Hardwired? The Role of Genes in Human Behavior (New York: Oxford University Press, 2000).
116Knauft, Bruce M., “Violence and sociality in human evolution,” Current Anthropology, 1991, 32(4): 391–409.
117Flack, J. C., Girvan, M., de Waal, F. B., and Krakauer, D. C., “Policing stabilizes construction of social niches in primates,” Nature, 2006, 439(7075): 426–429.
118de Waal, F. B. M., Chimpanzee Politics: Power and Sex Among Apes (Baltimore, MD: Johns Hopkins University Press, 1998).
119In this respect, too, international politics resembles animal behavior. As an alpha male provides stability to the group, so too a hegemon in international politics, as many scholars recognize, may provide stability for lesser states both in the realm of international security and for international political economy. On the importance of resource harvesting for the development of dominance hierarchies, see James L. Boone, “Competition, conflict, and the development of social hierarchies,” in Evolutionary Ecology and Human Behavior, Eric Alden Smith and Bruce Winterhalder, eds. (New York: Aldine de Gruyter, 1992), pp. 301–337.
120Kurzban, Robert and Neuberg, Steven, “Managing ingroup and outgroup relationships,” in The Handbook of Evolutionary Psychology, Buss, David M., ed. (New York: Wiley, 2005), pp. 653–675.
121Sidanius and Kurzban.
122Hewstone, Miles, Rubin, Mark, and Willis, Hazel, “Intergroup bias,” Annual Review of Psychology, 2002, 53: 575–604.
123Fiske, Susan T., “What we know about bias and intergroup conflict, problem of the century,” Current Directions in Psychological Science, 2002, 11(4): 123–128.
124Sidanius, Jim and Pratto, Felicia, Social Dominance: An Intergroup Theory of Social Hierarchy and Oppression (New York: Cambridge University Press, 2001).
125Alexander, Richard D., The Biology of Moral Systems (Aldine, NY: Hawthorne, 1987).
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130Guilaine and Zammit.
131LeBlanc and Register.
132Allen and Jones.
133Wrangham and Peterson.
136Sidanius and Kurzban.
138Tooby, John and Cosmides, Leda, “Groups in mind: The coalitional roots of war and morality,” in Human Morality and Sociality: Evolutionary and Comparative Perspectives, Høgh-Olesen, Henrik, ed. (New York: Palgrave MacMillan, 2010), pp. 191–234.
139Wrangham, 2009, p. 169.
140Manson and Wrangham.
142M. L. Wilson et al., 2014.
143Mech, L. D., Adams, L. G., Meier, T. J., Burch, J. W., and Dale, B. W., The Wolves of Denali (Minneapolis: University of Minnesota Press, 1998).
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145Cronk, Lee and Leech, Beth L., Meeting at Grand Central: Understanding the Social and Evolutionary Roots of Cooperation (Princeton, NJ: Princeton University Press, 2013).
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147Rozin, Paul and Royzman, Edward B., “Negativity bias, negativity dominance, and contagion,” Personality and Social Psychology Review, 2001, 5(4): 296–320.
148We thank Robert Jervis for bringing this point to our attention.
152McDermott, Rose, Presidential Leadership, Illness, and Decision Making (Cambridge: Cambridge University Press, 2007).
153McDermott, Rose, Political Psychology in International Relations (Ann Arbor: University of Michigan Press, 2004).
154Mearsheimer, 2001, p. 22.
155Davies, Nick B., Krebs, John R., and West, Stu A., An Introduction to Behavioural Ecology (Chichester, UK: Wiley Blackwell, 2012).
157Robertson, I. H, The Winner Effect: How Power Affects Your Brain (London: Bloomsbury, 2012).
159Gat, 2006, p. 427; see also Elizabeth Knowles, ed., Oxford Dictionary of Quotations (Oxford: Oxford University Press, 1999), p. 333.
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163Mearsheimer, 2001, p. 40.
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