9. BBC News online, July 16, 2003.
10. BBC News online, October 15, 2007.
11. Psychology Today, March/April 2001.
12. Barratt et al. (2009).
13. Hypothetically, one could try to falsify this hypothesis using data on testicular volume and sperm production from some of the societies we’ve discussed where sperm competition and partible paternity are in effect. To this end, we’ve contacted every anthropologist we could locate who has worked in the Amazon (or anywhere else with hunter-gatherers), but no one seems to have managed to gather these delicate data. Still, even if it were found that males in these societies showed higher testicular volume and sperm production, as our hypothesis predicts, definitive confirmation of the hypothesis would be precluded by the relative absence of the environmental toxins that are presumably at least partly responsible for testicular atrophy in industrialized societies.
14. BBC News online, December 8, 2006.
15. Diamond (1986).
16. W. A. Schonfeld, “Primary and Secondary Sexual Characteristics. Study of Their Development in Males from Birth through Maturity, with Biometric Study of Penis and Testes,” American Journal of Diseases in Children 65, 535-549 (cited in Short, 1979).
17. Harvey and May (1989).
18. Baker (1996), p. 316.
19. Bogucki (1999), p. 20.
1. Maines’s book has become an underground sensation. Written as a serious cultural history of the vibrator, the story
she tells is surprising and compelling. As we write, a play based on the book written by Sarah Ruhl (In the Next Room) is playing on Broadway. A National Public Radio story on the play is here: http://www.npr.org/templates/story/
story.php?storyId=20463597&ps = cprs.
2. Quotes taken from Margolis (2004).
3. See Money (2000). Interestingly, semen depletion is central to the ancient Taoist understanding of male health and sexuality as well. See, for example, Reid (1989).
4. On Baker Brown, see Fleming (1960) and Moscucci (1996).
5. Coventry (2000).
6. Although the clitoris is often referred to as “the only organ in the human body whose sole function is to provide pleasure,” there are two problems with this observation. First, if female orgasm (pleasure) is functional in the senses we outline (increases chances of fertilization, inspires vocalizations, and thereby promotes sperm competition), then there is clearly a purpose to the pleasure. Secondly, what about male nipples? Not all men find them to be a site of pleasure, but they are certainly highly enervated and serve no functional purpose.
7. Margolis (2004), pp. 242-243.
8. Ironically, according to archaeologist Timothy Taylor
(1996), this image of the Devil is thought to be derived from Cernunnos, the horned god, who was the Celtic translation of
Indian tantric practice and thus originally a symbol of spiritual transcendence via sexual practice.
9. Coventry (2000).
10. Hrdy (1999b), p. 259.
11. Sherfey (1972), p. 113.
1. Pinker (2002), p. 253.
2. Not to exclude women or gay men, but there is a dearth of scientific data on this particular angle. Interestingly, though, several people have reported to us anecdotally that when they’ve overheard their neighbors (both gay male and lesbian couples) having sex, the partner they considered to be the more feminine was the one who was making more noise.
3. When the director, Rob Reiner, showed the screenplay to his mother, she suggested that at the end of that scene, the camera cut to an older woman in the restaurant about to order, who says, “I’ll have what she’s having.” The line was so brilliant that Reiner told his mother he’d insert it, but only if she agreed to deliver the line in the film, which she did.
4. Semple (2001).
5. Small (1993), p. 142.
7. Dixson (1998), pp. 128-129.
8. Pradhan et al. (2006).
9. These quotes are from Hamilton and Arrowood (1978).
10. The intensity of the female’s vocalizations could, for example, guide the discerning male’s orgasmic response—thus increasing the chances of simultaneous or near-simultaneous orgasm. As we discuss below, there is evidence such timing could be to the male’s reproductive advantage.
11. The title, far from being the frat-boy declaration it may seem (“Without tits, there is no paradise.”), is the name of a Colombian television drama about young women who get breast implants hoping to attract the attentions of local drug lords and thereby escape poverty.
12. For example, Symons (1979) and Wright (1994).
13. See Morris (1967), Diamond (1991), and Fisher (1992).
14. http://dir.salon.com/story/mwt/style/2002/05/28/ booty_call/.
15. Though they can be considered permanently swollen, this is not to say that breasts don’t change throughout a woman’s life (and menstrual) cycle. They typically swell further at pregnancy, menstruation, and orgasm (up to 25 percent greater than normal, according to Sherfey), and diminish in size and fullness with age and breastfeeding.
16. Small (1993), p. 128.
17. Haselton et al. (2007). Available online at www.sciencedirect.com.
18. Many accounts of human sexuality incorporate this explanation, but that of Desmond Morris is probably still the most widely known.
19. Dixson (1998), pp. 133-134.
20. Dixson refers specifically to macaques and chimps in this passage, though he’s speaking of the capacity for multiple orgasm in female primates in general in the section where the passage appears. Passages like this led us to wonder why Dixson hadn’t followed the data to where they seem to so clearly lead. We sent him an email outlining our argument and requesting his comments and criticisms, but if he received our message, he chose not to respond.
21. Symons (1979), p. 89.
22. Lloyd, a former student of Stephen Jay Gould, recently
published an entire book in which she reviews (and rather contemptuously dismisses) the various adaptive arguments for the female orgasm (The Case of the Female Orgasm: Bias in the Science of Evolution). For a sense of why we don’t recommend her book, take a look at David Barash’s review, available online (“Let a Thousand Orgasms Bloom”). Download at http://www.epjournal.net/filestore/
ep03347354.pdf.
23. As noted above, some of the findings of Baker and Bellis are highly controversial. We mention them because they are known to many in the general audience, but none of their findings are necessary to our argument.
24. Barratt et al. (2009). Available online at http://jbiol.com/ content/8/7/63.
25. Pusey (2001).
26. Both quotes appear in Potts and Short (1999). The first quote is from the main text, page 38, and the second is quoting Laura Betzig, p. 39.
27. Dixson (1998), pp. 269-271. An excellent review of the development of the concept of postcopulatory sexual selection can be found in Birkhead (2000). Copious evidence for this filtering function can be found in Eberhard (1996), where the author presents dozens of examples of females exerting “post-copulatory control” over which sperm fertilize their eggs.