There're lots of interesting bits in my Evolutionary Psychology textbook, but I'd rather spend my leisure time killing berks in Sigil, watching my Bakuryu Sentai Abaranger subs and viewing the webcast for a makeup lecture where nothing was new, so what the hell, I'll just skip to the chapter on Short Term Mating and transcribe all the juicy bits.

After all, that's what everyone loves - casual, mindless sex!


"Imagine an attractive person of the opposite sex walking up to you on a college campus and saying "Hi, I've been noticing you around town lately, and I find you very attractive. Would you have sex with me?" How would you respond? If you were like 100 percent of the women in one study, you would give an emphatic no. You would be offended, insulted or just plain puzzled by the request. But if you were like the men in that study, the odds are good that you would say yes - as did 75 percent of those men (Clarke & Hatfield, 1989). As a man you would most likely be flattered by the request. Many of the 25 percent of the men who declined the sexual offer were apologetic, citing previous commitments. The idea that men and women react differently when it comes to casual sex may not be surprising. Theories in evolutionary psychology, however, provide a principled basis for predicting this difference and for explaining its magnitude." (pp. 163)

"Men's testes size, relative to their body weight, is far greater than that of gorillas and orangutans. Male testes account for .018 percent of body weight in gorillas and .048 percent in orangutans (Short, 1979; Smith, 1984). In contrast, human male testes account for .079 percent of men's body weight, or 60 percent more than that of orangutans and more than four times that of gorillas, corrected for body size. Men's relatively large testes provide one solid piece of evidence that women in human evolutionary history sometimes had sex with more than one man within a time span of a few days... Human testicular volume is substantially smaller than that of the highly promiscuous chimpanzee, whose testes account for .269 percent of its body weight, more than three times than the percentage for men." (pp. 168)

"Men's sperm count went up dramatically with the increasing amount of time the couple had been apart since their last sexual encounter... When the couples spent 100 percent of their time together, men inseminated 389 million sperm per ejaculate, on average. But when the couples spent only 5 percent of their time together, men inseminated 712 million sperm per ejaculate, almost double the amount... It is important to note that this increase in sperm insemination upon being reunited did not depend on the time since the man's last ejaculation. Even when the man had masturbated to orgasm while away from his wife, he still inseminated more sperm on being reunited if he had been away from her a long time." (Baker & Bellis, 1995) (pp. 168)

"Another study analyzed forty-eight "private wishes" ranging from "to be with God when I die" to "to make a lasting contribution through creative work" (Ehrlichman & Eichenstein, 1992). The largest sex difference by far was found for one wish: "to have sex with anyone I choose."" (pp. 169)

"Evolutionary psychologist Martie Haselton recently found evidence for a possibly adaptation in men to facilitate the success of a short-term mating strategy: an emotional shift right after sexual intercourse (Haselton & Buss, 2001). Men with more sex partners experienced a sharp decline in how sexually attractive they found their partner immediately following intercourse, whereas neither women nor men with less sexual experience showed this decline. If further work verifies the attraction-reduction effect, it might support the hypothesis that men have yet another psychological adaptation designed to promote the success of a casual sexual strategy, one that motivates either a hasty postcopulatory departure to minimize investment in any one women or, alternatively, a roving eye within the context on an existing long-term mateship." (pp. 172)


"Forty-three percent of women but only 12 percent of men report that they never substitute or switch sexual partners during a fantasy episode. Thirty-two percent of men but only 8 percent of women report having imagined sexual encounters with more than 1,000 different partners in their lifetime. A sample male fantasy is "being the mayor of a small town filled with nude girls from 20 to 24. I like to take walks, and pick out the best-looking one that day, and she engages in intercourse with me. All the women have sex with me any time I want" (Barclay, 1973, p. 209). Numbers and novelty are key ingredients of men's fantasy lives.

Men focus on body parts and sexual positions stripped of emotional context. Male sexual fantasies are heavily visual, focusing on smooth skin and moving body parts. During sexual fantasy, 81 percent of men but only 43 percent of women focus on visual images rather than feelings. Attractive women with lots of exposed skin who show signs of easy access and no commitment are the frequent contents of men's fantasies. As evolutionary psychologists Bruce Ellis and Donald Symons observed, "The most striking feature of [male fantasy] is that sex is sheer lust and physical gratification, devoid of encumbering relationships, emotional elaboration, complicated plot lines, flirtation, courtship, and extended foreplay (Ellis & Symons, 1990, p. 544)... Women emphasize tenderness, romance and personal involvement in their sexual fantasies. Women pay more attention to the way their partner responds to them rather than to visual images of their partner (Ellis & Symons, 1990)"


"Anthropologist Thomas Gregor described the sexual feelings of Amazonian Mehinaku men in this way: "Women's sexual attractiveness varies from 'flavorless' (mana) to the 'delicious' (awirintya)..." (1985, p. 84). Furthermore, Gregor notes that "sad to say, sex with spouses is said to be mana, in contrast to sex with lovers, which is nearly always awirintyapa" (Gregor, 1985, p. 72)." (pp. 175)

"The number of sperm a woman retains is also linked with whether she is having an affair. Women time their adulterous liaisons in a way that is reproductively detrimental to their husbands. In a nationwide sex survey of 3,679 women in Britain, all women recorded their menstrual cycles as well as the timing of their copulations with their husbands and, if they were having affairs, with their loves. It turned out that women having affairs appeared to time their copulations, most likely unconsciously, to coincide with the point in their menstrual cycle when they were most likely to be ovulating and hence were most likely to conceive (Baker & Bellis, 1995). Furthermore, women who are having affairs are more likely to be orgasmic with their affair partner than with their regular partner. (see Buss, 2003)." (pp. 177)

"The absence of a father while growing up has been reliably linked with the pursuit of a short-term mating strategy. Among the Mayan of Belize and the Ache of Paraguay, for example... Other studies of both women and men have found that those growing in father-absent homes are more likely to reach puberty sooner, to engage in sexual intercourse earlier, and to pursue a short-term mating strategy (e.g., Ellis, McFadyen-Ketchum, Dodge, Pettis, & Bates, 1999; Surbey, 1998). Intriguingly, one study found that stepfather presence, even more than biological father absence, may be the critical factor promoting early sexual maturation in girls - a likely precursor to the pursuit of a short-term mating strategy (Ellis & Garber, 2000)... Finally, poor attachment to one's parents was linked to a higher likelihood of reading pornography among women, and predicted sexual promiscuity for both sexes (Walsh, 1995, 1999)." (pp. 183-184)

"The fact that premarital adolescent sexual experimentation is tolerated and even encouraged in some cultures, such as the Mehinaku of Amazonia (Gregor, 1985), provides a clue that short-term mating is related to one's stage in life." (pp. 184)

"For women, however, self-esteem proved to be a highly significant predictor of short-term mating. Women scoring low on self-esteem, relative to their high self-esteem counterparts, tended to have a greater number of sex partners since puberty, a greater number of sex partners over the past year, a greater number of one-night stands, a preference for short-term sexual relationships, and scores on the SOI indicating the pursuit of a short-term mating strategy." (pp. 185)

(All quotes from David M. Buss, Evolutionary Psychology - the New Science of the Mind, Second Edition, 2004)