Rhawn Joseph, Ph.D.
Brain Research Laboratory
A review of world wide statistics for prostitution and infection rates for sexually transmitted disease, and the literature on animal sexual behavior was conducted, and it was concluded that on average, females have more sex partners than the average male. Over 200 million women work as prostitutes and they have sex with an estimated 694 to 1000 (or more) men a year and with over 5,000 men during their career. The average male has fewer than 10 sex partners in a life time. Females become infected with sexually transmitted diseases at a rate 2.5 to 5 times that of males, which suggests a relatively larger percentage of females are having sex with a relatively smaller percentage of males. A review of the animal literature also indicates non-human females have more sex partners, on average, as compared to males. Females of many species, including humans, preferentially and repeatedly mate with (a relatively small percentage of) high status males while refusing sex with (the relatively higher percentage of) low status males. Males also experience a "refractory period" following orgasm, whereas females are capable of experiencing multiple orgasms and multiple sex partners, one after another, all of which contributes to the fact that females, on average, have more sex partners than the average male.
Men are supposedly more desirous of sex and have more sex partners than women on average, according to "conventional wisdom" and as reported in all surveys on sex differences in sexual activity (Abma et al., 1997; Davis, & Smith, 1994; Greer & Buss, 1994; Hite, 1981; Kinsey et al., 1953; Laumann et al., 1994; Sprecher & MecKinney, 1993; Valois, Kammermann, & Drane, 1997). However, if these reports are accurate, we would be forced to conclude that humans differ from almost all other species surveyed. Stereotypically, almost regardless of all species, nearly all adult females will mate, often with multiple male sex partners. By contrast, a significant minority of males, and in some species, the majority of males, never have a sex partner (Bateman, 1948; Cade, 1985; Clutton-Brock, 1987; Howard, 1978; Lott, 1979; McCann, 1981; Thornhill, 1981; Trivers, 1976). Females generally have more sex and more sex partners than the average male, and this is also the case for many species of primate (Carpenter, 1942; Hausfater, 1975; Lancaster, 1978; Seyfarth, 1977; Smuts, 1987; Tutin, 1975; Zuckerman, 1932).
"Get them up. Get them off. And Get them out."
-Motto in a house of prostitution
As first detailed by Joseph, (2000a) and as recently supported by findings reported by Brewer et. al., (2000) conventional wisdom and the results from all published sex surveys have failed to include or take into consideration the sexual activity of female prostitutes. In consequence, the authors of these surveys have falsely reported that males have more sex partners on average.
According to the 1998 report of the International Labor Organization (1998) and the Coalition Against Trafficking in Women (Hughes, 2000), over 200 million women world wide work as prostitutes and have sex with over 5 men a "working" day. In fact, as a man can ejaculate within a matter of minutes, a prostitute working in a busy brothel may have sex with up to 5 men in just a few hours.
Brewer et al. (2000) estimate that the average American prostitute has 694 partners a year. Based on income, crime statistics, and physiological variables, Joseph (2000a) estimates that world-wide, a full time prostitute may have sex with over a 1000 men a year; though the actual figure may be much higher.
In some countries up to 30% of young adult females work as prostitutes, with the sex industry accounting for up to 14% of the gross domestic product (International Labor Organization, 1998; Hughes, 2000). In Indonesia, for example, the gross income from prostitution is around 3.6 billion dollars, whereas in Thailand the income is almost 27 billion dollars annually (Hughes, 2000; International Labor Organization, 1998).
Thus based on labor statistics and the income generated, it appears that world wide over 200 million women, over 10% of the adult female population, have sex with 694 to over 1000 men a year. And, the majority of these women probably have sex with over five thousand men each, during the course of their working career. Although it is true that a few professional athletes and male movies stars have claimed to have had sex with thousands of women, these males are the exception as most males instead tend to report (on average) fewer than 10 sex partners in a life time (Davis & Smith, 1994; Greer & Buss, 1994; Kinsey et al., 1953; Laumann et al., 1994; Sprecher & MecKinney, 1993; Valois et al., 1997).
Sexually Transmitted Diseases
When prostitutes and sex differences in infection rate for sexually transmitted diseases (SDS) are considered, it can be deduced that women in general have more sex and more sex partners than males on average (Joseph, 2000a), which is also the case with most other species (Bateman, 1948; Cade. 1985; Carpenter, 1942; Clutton-Brock, 1987; Hausfater, 1975; Howard, 1978; Lancaster, 1978; Lott, 1979; McCann, 1981; Thornhill, 1981; Trivers, 1976; Seyfarth, 1977; Smuts, 1987; Tutin, 1975; Zuckerman, 1932). In fact, these sex differences in human sexual activity can be deduced based on the percentage of males vs females who become infected with SDS (Joseph, 2000a).
Data provided by the Centers for Disease Control (1991, 1996, 1997a,b;), Webster and colleagues (1991; Webster, Berman, and Greenspan, 1991; Webster & Rolfs, 1991), and the World Heath Organization (2000), indicate that females have a significantly higher rate of infection for HIV, gonorrhea, syphilis, and chlamydia, and that females between the ages of 15 and 19, have the highest infection rate of all age groups.
For example, in both 1991 and 1995, over half a million cases of chlamydia in the United States were reported, and the rate of infection for young females was found to be six time higher than for men, with an incidence of rate of 290.3 per 100,000 for females, versus 52 per 100,000 for males (Centers for Disease Control, 1991, 1997a; Webster et al., 1991).
In addition, females in the U.S., have a syphilis infection rate that is 2 to 5.5 times higher than males, with a 35 per 100,000 incidence rate for adult females versus 18 per 100,000 for adult males (Centers for Disease Control, 1991, 1996, 1997a; Webster et al. 1991). Females aged 10-14 have a syphilis infection rate that is 5.5 times higher than males their own age (Centers for Disease Control, 1991). Likewise, the incidence of gonorrhea among females aged 15-19 is 1,043.6 per 100,000 vs 882.6 per 100,000 for males (Centers for Disease Control, 1991; Webster et al. 1991).
Moreover, as based on an analysis of 36 countries, it was found that women under age 20 have twice the rate of infection with the AIDs virus than do young males and that the HIV infection rate is highest for women between the ages of 15 and 25 (World Health Organization, 2000). Among American youths, the HIV rate is about 4.2 per 1,000 girls, versus 2.0 per 1000 boys. Regardless of age, the HIV rate for men never equals that of women (World Health Organization, 2000) which argues against the notion that an equal number of older men are infecting an equal number of younger women.
Females Preferentially Mate with High Status Males
Based on sex differences in the rate of SDS, coupled with the world wide statistics regarding prostitution, it appears that a relatively larger percentage of females are repeatedly having sex with a much smaller percentage of males, and that a small percentage of males are having sex with multiple female sex partners including prostitutes (Joseph, 2000a); which is exactly the case among other species.
For example, a significant minority, and in some species, the majority of males never have sex as females refuse to mate with them due to the male's low status or lack of resources (Bateman, 1948; Carpenter, 1942; Clutton-Brock, 1987; Hausfater, 1975; Howard, 1978; Lancaster, 1978; Lott, 1979; McCann, 1981; Thornhill, 1981; Trivers, 1976; Seyfarth, 1977; Smuts, 1987; Tutin, 1975; Zuckerman, 1932). Among insects it has been reported that 85% of the females are mated by less than 5% of all males (Cade, 1985).
Non-human primate females, such as baboons, rhesus, and chimpanzees, seek out and have sex with high ranked males and avoid lower ranking, and in particular the lowest ranked males (Carpenter, 1942; Hausfater, 1975; Lancaster, 1978; Seyfarth, 1977; Smuts, 1987; Tutin, 1975; Zuckerman, 1932). The female will refuse sex by lowering her hindquarters.
Although an estrus female chimp may copulate up to 50 times in a day, and although she may have up to 20 or more males to choose from, she may instead choose to repeatedly mate with only 8 of the available males who generally tend to be of high status (Goodall, 1986; Tutin, 1975).
In polygynous primate species, only perhaps 25% of the males ever mate (Fedigan, 1992). In one colony of free ranging rhesus monkeys, although there were 150 adult females and 52 males, most of the estrus females actively sought out and mated with the same three dominate males (Carpenter, 1942). In some colonies, only about 20% of the males are responsible for 80% of the matings (Freedman, 1979). Similarly, in one study of 25 male and 25 female captive baboons, it was observed that the females mated selectively with only five of the males (Zuckerman, 1932).
Even among highly promiscuous primates, such as chimpanzees, low ranking males often have difficulty obtaining sex due to male competition and female choice (Goodall, 1986; Nishida, 1990; Sade, 1967; Small, 1989; Smuts, 1987; Taub, 1980). High status males tend to drive them away whereas females may avoid them or lower their hindquarters and refuse to cooperate. As noted by Lancaster (1978, p. 68) "fieldwork publications are filled with reports of females... refusing copulation attempts by keeping their hindquarters lowered." In fact, among low status male primates, if they do gain access to a female it is usually only before she fully enters estrus and after she ends her estrus.
Likewise, human females preferentially seek to mate with high status, successful, powerful, popular, wealthy, athletic, physically attractive, and handsome men--who come in limited numbers. The higher his status and the greater his resources the greater is the likelihood that females will choose to mate with him (Buss, 1994; Betzig, 1985; Betzig et al., 1988; Symons, 1979; Townsend, 1989). By contrast, most men rank female job security and salary as having little importance when deciding on a sex partner (Buss, 1987; Howard et al. 1987; Weiderman, 1997; Woll, 1986).
Hence, in consequence, as high status men come in limited numbers and are less choosy when it comes to sex partners, a relatively larger percentage of females will have sex with a relatively smaller percentage of males. Therefore, whereas almost all women are provided multiple opportunities to mate with low and high status males, only a relatively small percentage of males are provided with multiple willing females. This explains the sex differences in the infection rate for sexually transmitted diseases.
Promiscuity & The Multi-Orgasmic Female
Yet another major factor contributing to this sex differences in sexual activity is the human female's biological capacity to enjoy multiple sex partners and multiple orgasms, often one after the other (Joseph 2000a).
According to Masters and Johnson (1966) "if a woman who is capable of regular orgasms is properly stimulated after the first climax, she is capable of having a second, third, fourth, and even fifth and sixth orgasm within a matter of minutes." Subsequent orgasms are even more satisfying and pleasurable than the first. Even women who are described as "frigid" by the strictest of standards, are capable of experiencing intense multiple orgasms following therapy. As determined by Masters and Johnson (1966) the human female is capable of having "20 to 50 consecutive orgasms. She will stop only when totally exhausted."
More recent studies, however, indicate that only about 42% of women admit to experiencing multiple orgasms (Darling et al., 1991). Nevertheless, those who admit to experiencing multiple orgasms are more sexually assertive and willing to engage in a variety of sexual activities and tend to feel less restricted by societal norms (Darling et al., 1991). Thus, they are more likely to seek out multiple partners and to expect multiple orgasms.
Indeed, the more a woman enjoys sex, and the more open she is to her sexuality, the more likely she is to seek out multiple sex partners (Bellis & Baker, 1990; Haavio-Mannila and Kontula, 1997; Wyatt et al., 1993), and, this includes those women in supposedly monogamous relationships (Betzig, et al., 1988; Haavio-Mannila & Kontula, 1997; Kinsey et al., 1953; Wyatt et al., 1993). A common female fantasy even among married women is to have an affair (Friday, 1991).
Likewise, species of female primate capable of experiencing multiple orgasms are not monogamous (Allen & Lemmon, 1981; Burton, 1971; Chevalier-Skolnikoff, 1974), and will aggressively solicit male after male for sex (Goodall, 1986). A single male is not biologically capable of providing the stimulation necessary for multiple orgasms and often is unable to provide sufficient stimulation for a single orgasm. In consequence, the sexually aroused female will aggressively seek sex with multiple males (Joseph, 2000a).
Unlike females, human males and other male primates quickly become drowsy and sexually unresponsive due to the experience of a "refractory period" following their own orgasm (Goodall, 1986; Masters & Johnson, 1966; Yerkes, 1939). The refractory period may last minutes or hours before the male is capable of getting a second erection, and the same is true of other species. For example, the male chimp takes only 10 to 15 seconds to ejaculate before experiencing a prolonged refractory period in which he becomes drowsy and disinterested in sex (Goodall, 1986; Yerkes, 1939).
In fact, primate males such as the rhesus, howler, gorilla, and chimpanzee, typically become unresponsive to the aggressive sexual solicitation of the female after three or four ejaculations in a single day, and cease to respond after three or four days of sexual activity (Carpenter, 1942; Goodall, 1986; Nadler, 1976; Schaller, 1964; Yerkes & Elder, 1936; Zuckerman, 1932). In these and other species, the sexual hunger of the multi-orgasmic female, and her capacity for copulation completely exceeds that of any single male which is yet another reason why she will stereotypically solicit male after male for sex .
"A single estrus female may satiate, entirely... several sexually vigorous males" (Carpenter, 1942, p. 141). Female chimps, baboons, gorillas, and monkeys, are capable of exhausting male and after male without showing any lessening of sexual desire (Carpenter, 1942; Goodall, 1986; Ford & Beach, 1951; Zuckerman, 1932). The same appears to be true of the human female. Whereas the female chimpanzee may have sex 50 times in a single day (Goodall, 1986), the human female can have up to 50 orgasms in just a few hours (Masters & Johnson, 1966).
As argued by Joseph (2000a) the human female is biologically predisposed to have sex with multiple sex partners, which is why she has inherited the capacity to experience multiple orgasms as well as an enlarged derriere and prominent breasts which serve to continually signal her sexual status and attract male sex partners (Joseph, 2000b). However, as with other species, it is likely that she seeks out multiple partners not just for pleasure, but as multiple partners insures she will become pregnant and that she will be exposed to multiple males offering her resources in exchange for sex.
From the data based on prostitution, sex differences in the infection rate for SDS, and studies of animal sexual behavior, it appears reasonable to conclude that on average, females are more sexually active and have more sexual partners, than the average male, and that they have a biological propensity to seek sex with multiple male partners. Even in the most restrictive of societies where they may be punished with death, it has been reported that some females will readily commit adultry or avail themselves of multiple sex partners who generally must be of "high status" or "handsome" (Kinsey et al., 1953; Sasson, 1992).
As determined almost half a century ago by Ford and Beach (1951, pp. 101-102), "in most societies... girls and women actively seek sexual liaisons with men, even though they are not supposed to do so... and in a few societies... the girl generally begins all the love affairs."
However, whereas a man may gain status and prestige by claiming multiple sex partners, the same is not true of women who may be verbally and physically attacked not just by men, but by other women (Joseph, 1985, 2000a; Scotts, Shifman, Orr, Owen, & Fawcet, 1988). Thus, men tend to exaggerate and women tend to minimize the number of their sex partners. Coupled with the failure to include prostitutes, or to consider sex differences in SDS, in consequence, all studies and surveys based on self-report, have erroneously concluded that males, on average, have more sex partners.
As is the case with other species, human females are more willing to have sex with high status males, which come in limited numbers. In consequence, a relatively small percentage of males, and a larger percentage of females, experience multiple sex partners, whereas "average" and low status males have comparatively limited sexual opportunities. Moreover, like other primates, whereas males experience prolonged refractory periods, human females are capable of experiencing multiple orgasms and multiple sex partners, often one after another; which is yet another reason why females may have more sex.