Promiscuity

Promiscuity refers to mating with many different partners, possibly strangers, which is often accompanied by low mate choice standards and a high sexual drive. The opposite mating pattern is monogamy which refers to sexual exclusivity (pair boding) and often involves high mate choice standards. Promiscuity is often accompanied by a desire for sexual variety. In behavioral science, the effect of becoming bored of the current mate in order to increase sexual variety is called Coolidge effect.

In humans, there are large differences in promiscuity in terms of sex outside committed relationships. Female promiscuity, but not male promiscuity, is often driven by access to resources. Further, female promiscuity still involves much higher mate standards compared to males. Female promiscuity also rather occurs more within a pre-selected group of males and backup partners, compared to males who would much more readily copulate with a stranger.

Evolutionary explanation

The advantage of promiscuity (from the point of view of the genes) is that it creates lots of offspring that one does not invest into, some of which may make it. More r-selected species are more promiscuous as they invest less in their offspring. In welfare states men can maximize reproductive success by pumping and dumping many females and leaving the raising of the offspring to single mothers supported by the state and/or betabux.

The advantage of sexual variety is also that it increases genetic variety. Combining one's own genes with the genes of many different sex partners increases the chance that one combination is particularly successful, as it increases the genotypic and hence phenotypic diversity of the offspring (with increased variance, both good and bad extreme outcomes become more likely). When combined with a low investment strategy, the bad offspring poses no cost.

Coolidge effect

The effect of becoming bored with the current mate is especially present in males of many animals, including humans. Pornography constitutes a superstimulus in this regard, allowing men to constantly being confronted with a sexually willing female, albeit on a screen.

Sex differences in promiscuity

As females often have much higher parental investment, the males are usually much more promiscuous, because females have to lock down a provider male as they are too invested in raising the offspring to gather resources themselves. As a result, men tend face higher variance in their reproductive success, which is referred to as Bateman's principle.

Both males and females, benefit from sexual variety (though females only if a source of resources is secured). The threat of extra-marital sex on the part of females means that men need to engage mate guarding in order to ensure paternity and avoid wasting their resources on another man's offspring. This motivates males to heavily constrain female sexuality, which is a near universal feature of human monogamous/polygynous mating systems, which sometimes even involved infanticide of offspring that were suspect or the homicide of the wife and/or lover. This constitutes a sexual conflict, with males opposing female whoring, engagement in pump and dump and infidelity.

Female promiscuity gives rise to sperm competition as it means the sperm needs to compete inside the vagina and possibly also affecting shape of the penis so as to be able to scoop out competing sperm. There is some (limited) evidence of female promiscuity in humans, which may have been more prevalent in close ancestor species with faster life history speed, but is still vestigial in certain human behaviors observable today.

Female promiscuity is also referred to as cock carousel.

Sperm competition vs reproductive success and sexual conflict

Fruit fly semen contains a chemical that acts as an anti-aphrodisiac on the female, so as to prevent her from mating with other males, as well as other chemicals that increase egg production rate in the females and other chemicals that incapacitate rival sperm. This is an example of the effects of sexual promiscuity on sexual conflict; we can in the instance of these fruit flies that males can evolve adaptations that increase their reproductive success at the expense of the female. In such instances females would evolve adaptions so as to defend herself against these harmful adaptations in males. In experiments were this co-evolution was halted in female fruit flies, males evolved sperm that became progressively more damaging to females. Interestingly in experiments were monogamy was enforced in fruit flies (so as the reproductive interests of the male and female converged) the semen in males became decreasingly toxic to females and males became less agressive. Interestingly, reproductive output (thus reproductive success) was greater than what it was when sperm competition was present. This demonstrates that when lifelong sexual monogamy is implemented, the reproductive interests of males and females converge (as they share offspring) and behaviours that are developed in one sex that are harmful to the other are selected against. Similiarly, it would be in the interests of humans to enforce lifelong monogamy (serial monogamy through divorce and remarriage is essentially promiscuity vertically across time rather than horizontally in the present) so as to discourage the development harmful behaviours in either sex against the other (like rape).

Human female promiscuity

Evidence against human female promiscuity:

• Sperm volume and testes size much smaller than pan with promiscuous females
• Cross-culturally high prevalence of monogamy, very low incidence rate of polyamory
• Despite sexual liberation, no evidence of widespread promiscuity and still very low non-paternity rates
• The simple shape shape of the Human Penis in comparison to promiscuous mating systems
• We've evolved out of a polygynous mating system like the Gorilla; promiscuous mating systems mating systems in Chimpanzees only evolved after they split from our lineage as evidenced by genes on the Y chromosome involved in sperm production.
• People in highly committed relationships tend to view attractive people as less attractive when compared to people that are single. Also as relationship length increases, partners tend to percieve their partners as more attractive than they actually are.
• The Oviduct in Human Females is much shorter and does not coil as much as more promiscuous primates (longer and more complex oviducts and selected for as a means to 'test' the sperm of the males so as to select the best sperm; a shorter oviduct would thus suggest little need for selecting superior sperm in males and thus implies sperm competition is minimal/non-existent)
• The relatively small midpiece of human sperm required (comparable to the Gorilla) which indicates a monogamous mating system as larger midpieces are found in promiscuous mating systems; specifically the human sperm midpiece has 15 mitochondria, much less than what can be found in the chimpanzee.
• The Vas Deferens is long and thin in humans (something that is typical of species with low levels of sperm competition)
• Low rates of Extra-pair paternity despite the widespread use of contraception. If the dual-mating hypothesis were true and women were adapted to cuckold their husbands with men with superior genes, contraception should make this much easier to achieve; thus we should see an increase in the number of Extra-pair paternity cases (as that's what women should've been adapted for) but we don't. One study measuring Extra-pair paternity over the last 400 years (well before the advent of extremely effective contraception) found, on average, an Extra-paternity rate of 0.46%-1.76%. Simliar conclusions were made elsewhere. That Extra-pair paternity has remained relatively stable, despite being easier to accomplish, undermines that dual-mating hypothesis that women seek to procure good genes from their affair partners.
• The rate of extra-pair paternity is low when compared to the rate of infidilety. Roughly 1.5% EPP to 13% of women who engage in adultery. If infidelity has been selected for the purpose of procuring good genes, then it is puzzling why the ratio of rate EPP to rate of adultery is only about 1 : 8.6 as we would expect much higher.

Evidence for human female promiscuity (with counter-arguments):

• Cross-cultural concerns about female promiscuity, giving rise to slut-shaming gossip among females
  • However, we hardly find slut shaming in Chimpanzees and other promiscuous mating systems; thus, this slut-shaming would rather be a feature of a species with a strong female-male resource dependence and a monogamous mating system were women stand to lose much if their pair bonded male leaves them, or not marry and settle down with her, because there are other females whom will more readily give him sex.
• Women have louder and more complex copulatory vocalizations (moaning) which is indicative of promiscuous mating behavior in other great apes. This at least suggests that in close human ancestors, the females were quite promiscuous, suggesting it is a vestigial behavior from predecessor in which parental investment had a lower significance for reproductive success. See female orgasm.
• Women display a kind of Coolidge Effect in marriages sooner than men
  • However, considering that women need to be more invested in parenting, it seems certainly plausible that women get sexually bored quicker than men (if you're getting pregnant too often, then who takes care of the kids).
• High incidence of mate poaching, mate switching, back-burners and relationship instability and a massive decline in long-term monogamous mating in contemporary "liberated" society.
  • This point is less about female promiscuity and is more evidence of female hypergamy, now that alpha males are more readily available and casual sex is more acceptable, the hypergamous instinct in females intensifies. Back up partners and mate switching is evidence that, when possible, a woman will trade her current partner out for a better mate. To argue for a promiscuous mating system, we need to show that a woman will still exhibit this behaviour even when paired with alpha males; even chimpanzees will mate with lower status males from time to time in their promiscuous mating system despite the availability of Chads to have sex with females. As it doesn't seem plausible that most females will exhibit mate switching/poaching whilst with Alpha men, this cannot be used as evidence of female promiscuity in Humans.
• In the Himba tribe of North-Western Namibia and Southern Angola women who cuckold their husbands by having children with other men are more reproductively successful than those who don't (somewhere between 17%-48% of children are not sired by their fathers as compared to the low rate of extra pair paternity of 3% in western countries).
  • Whilst this is certainly interesting to look at, it is unlikely that the conditions that allow women whom cuckold their husbands in the Himba tribe are widespread. For one, men are aware whose children are genetically their and those whom aren't (they are reffered to as 'omaka') and both women and men regularly engage in adultery (seemingly openly). The reason why the women whom cuckold their husbands enjoy greater greater reproductive success is two fold.
    Firstly favouring genetic children over omaka is genrally frowned upon, this is the exception rather than the rule when it comes to how men deal with children in humans. Almost no other culture in history would condemn a man for favouring his own children over other children; the only modern exception to this would be regressive France that criminilized paternity tests. Secondly the actual fathers of the omaka often give food to the women they've had children with. So the greater reproductive success essentially comes from the fact that women receive resources from both their husbands and lovers and would thus have healthier children and lower mortality rates.
    Finally when a man dies, his sister inherits his possessions not his children; this essentially lowers the cost of him being cuckolded by other men as he invests less into his children. Interesting to note that most marriages in the Himba are arranged (the women have no say) and that 'love matches' (marriages were the women has married for love) experienced lower rates of extra-pair paternity. Now whilst it might be interesting to study, it would be fallacious to assume that simply because this one tribe that displays a chimpanzee like mating system therefore ancestral females were promiscuous, they were not.
    The genetic and morphological presented above opposing rampant female promiscuity is reflective of millions of years of evolution and is a far better indicator of what ancestral females were like.

In summary, due to high female resource dependence and parental investment, and other factors mentioned, female promiscuity appears to be limited to a minority of women with a fast life history disposition or women who temporarily fall for feminist dating advice, and assertions about high female promiscuity may rather stem from an innate male sensitivity about paternity assurance and from men losing status via getting cucked or mogged. It likely also owes to the tendency of women to engage provocative sexual advertisements (in order to attract male attention, marry up and/or get resources) in the absence of high standards of behavioral conduct (usually in view of gaining attention from men), as opposed to it reflecting particularly high rates of promiscuity among modern females.

Playing with men's ancient emotions

Main article: Orgasms for resources

There is a converging body of evidence of women exploiting the ancient sensitivities in men about paternity assurance, promiscuity, sperm competition etc. so as to provoke men's investment. For example, a women in a stable relationship might engage in flirting to provoke their current provider's envy, leading him to invest more into her and regain her exclusive sexual access. In men, such kind of simping and envy and falling for such trickery would in fact even be adaptive in modern men as it ensures a greater parental investment. This entire adaption complex in modern more K-selected humans could be thought of as repurposing more ancient adaptations for men spreading their seed far and wide, in order to ensure a greater parental investment.

This might serve as additional explanation besides the immanent material and psychological costs associated with straying women such as single motherhood or investment into other men's offspring. Relatedly, women are seen to feign sexual willingness or sexual neediness (as evidenced by almost half of women reporting to be not sexually satisfied enough), seemingly with the same purpose of getting access to men's resources, or using a switch-and-bait manipulation tactic wherein they first pretend to sell sex cheaply to then switch back to their coyness and sell it at a higher price.

Promiscuity and health

Promiscuity is known to increase chances of sexually transmitted diseases and also chances of unwanted pregnancies. Nonetheless, promiscuous women in the U.S. are not found to be particularly unhappy, nor are highly promiscuous men particularly happy. Data from the General Social Survey (GSS) suggests 84% of the 5% most promiscuous women were happy; further there is only a 5% greater prevalence of unhappy individuals who are extremely promiscuous compared to the rest of women. Swingers who engage in wife-sharing also actually report greater happiness than others. Though provided many men do experience a high degree of sexual envy and an urge to mate guard when their partner flirts with another suitor, this suggests that female unfaithfulness may be a nuisance for some men more than for others, possibly explained by intra-individual differences in life history speed adaptations, though there also appears to be a strong cultural influence of the social acceptance of female promiscuity.

See also

• Human penis
• Pump and dump
• Slut
• Paternity assurance
• Microchimerism