and humans, see the collection of essays, Tree of Origin: What primate behavior can tell us about human social evolution (Cambridge: Harvard University Press, 2001). For a comparison of the speed of primate coitus, see Desmond Morris’s The Naked Ape (New York: McGraw-Hill, 1967). For an extended study of the evolution of pair-bonding, see Helen Fisher’s The Sex Contract (New York: William Morrow Publishing, 1982). R. L. Trivers’s famous essay can be found in Sexual Selection and the Descent of Man: The Darwinian Pivot (Piscataway, NJ: Transaction Publishers, 2006) edited by B. Campbell. For the willingness of men to have sex with strangers (and vice versa for women), see R. D. Clark and E. Hatfield, “Gender differences in receptivity to sexual offers,” Journal of Psychiatry and Human Sexuality 2:1 (1989): 39-55. For the differences between male and female fantasies, see D. Symons and B. Ellis, “Sex differences in sexual fantasy: An evolutionary psychology approach,” Journal of Sex Research 27:4 (November, 1990): 527-555. For men’s interest in their female friends, see A. Bleske and D. Buss, “Can men and women be just friends?” Personal Relationships 7:2 (June, 2000): 131-151. For the study on toxic fruit fly sperm, see William Rice, “Sexually antagonistic male adaptation triggered by experimental arrest of female evolution” in Nature 381 (May 16, 1996): 232-234. For female orgasm and sperm retention, see R. R. Baker and M. A. Ellis’s “Human sperm competition: Ejaculate manipulation by females and a function for the female orgasm,” Animal Behavior 46 (1993): 887-909. For one of the many studies about our addiction to deception, see Bella M. DePaulo, et al., “Lying in everyday life,” Journal of Personality and Social Psychology 70:5 (May, 1996): 979-995. For the theory that mating is the driving force in the development of our brains, see Geoffrey Miller’s The Mating Mind: How sexual choice shaped the evolution of human nature (New York: Doubleday, 2000). For the differences between male and female brains, see Louann Brizendine, The Female Brain (New York: Broadway Publishing, 2006). For the many-faceted effect of human attractiveness, see Nancy Ectoff’s Survival of the Prettiest: The science of beauty (New York: Doubleday, 1999). And for a study on the importance of the waist-to-hip ratio, see D. Singh’s “Body Shape and Women’s Attractiveness,” Human Nature 4:3 (September, 1993): 297-321.
For testicle size, penis size, and body dimorphism, see Jared Diamond’s The Third Chimpanzee: The evolution and future of the human animal (New York: Harper Collins, 1992). For a discussion of the advantages and disadvantages of monogamy and polygamy, see Robert Wright’s The Moral Animal: Why we are the way we are: The new science of evolutionary psychology (New York: Vintage Books, 1995).
For the indefatigable consumers out there, Barry Schwartz’s The Paradox of Choice: Why More is Less (New York: Harper Collins, 2004) is a remarkable exploration of the difficulties that too much choice creates for us. The happiness studies I mentioned for chapter 1 also provide a great deal of insight into our ability to make ourselves miserable. For the difficulty of too many jams, see S. Iyengar and M. Lepper, “When Choice is Demotivating: Can one desire too much of a good thing?” Journal of Personality and Social Psychology 79:6 (December, 2000): 995-1006. For the study on doctors’ difficulties when faced with multiple treatments, see D. A. Redelmeier and E. Shafir, “Medical decision making in situations that offer multiple alternatives,” Journal of the American Medical Association 273:4 (January, 1995): 302-305. For the indecisive photography students, see D. T. Gilbert and J. E. J. Ebert, “Decisions and Revisions: The affective forecasting of changeable outcomes,” Journal of Personality and Social Psychology 82:4 (April 2002): 503-514. For a study on how people prefer more relative income rather than absolute income compared to their neighbors, see S. Solnick and D. Hemenway, “Is more always better?: A survey of positional concerns,” Journal of