Adaptive Benefits for Men of Short-Term Mating•Over a one-year period, an ancestral man whomanaged to have short-term sexual encounters withdozens of fertile women would have caused manypregnancies•an increase in the number of offspring produced
Costs to long term mating for men(1) contracting sexually transmitted diseases, a risk thatincreases with the number of sex partners(2) acquiring a social reputation as a "womanizer,"which could impair their chances of finding a desirablelong-term mate3) lowering the chances that their children wouldsurvive owing to lack of paternal investment andprotection;
(4) suffering violence at the hands of jealous husbandsor mates if the women with whom they pursued thisstrategy were married or mated;5) suffering violence at the hands of the father orbrothers of the women(6) risking retaliatory affairs by their wives and thepotential for a costly divorce (Buss & Schmitt, 1993; Daly& Wilson, 1988; Freeman, 1983)
•The Problem of Partner Number or Variety•The Problem of Sexual Accessibility.•The Problem of Identifying Which Women Are Fertile.•The Problem of Avoiding Commitment
Physiological Evidence for Short-Term MatingTesticle Size--Sperm competition exerts a selectionpressure on males to produce large ejaculatescontaining numerous spermVariations in Sperm Insemination-Mens sperm count went up dramatically with theincreasing amount of time the couple had been apartsince their last sexual encounter
The number of sperm inseminated increases whenother mens sperm might be inside the wifesreproductive tract at the same time as a consequence ofthe opportunity provided for extramarital sexby the couples separation.
Desire for a Variety of Sex Partners-One psychologicalsolution to the problem of securing sexual access to a varietyof partners is lust: men have evolved a powerful desire for sex.Men do not always act on this desire, but it is a motivatingforce: "Even if only one impulse in a thousand isconsummated, the function of lust nonetheless is tomotivate sexual intercourse“(Buss & Schmitt, 1993)-research shows that men desire moresex partners than women at each of the different timeintervals
Another psychological solution to the problemof gaining sexual access to a variety of partners is to letlittle time elapse between meeting the desired femaleand seeking sexual intercourse.Mens greater likelihood of consenting to sexualintercourse after little time has elapsed has now beenextensively replicated in samples of varying ages andgeographical locations within the United States
The Lowering of Standards in Short-Term Mating.High standards for attributes such as age, intelligence,personality, and marital status function to exclude themajority of potential mates from consideration.Relaxedstandards ensure more eligible playersFor brief encounters men require a lower level of suchassets as charming, athletic, educated, generous, honest,independent, kind, intellectual, loyal, having a sense ofhumour, sociable, wealthy, responsible, spontaneous,cooperative, and emotionally stable.
Minimizing Commitment after Sex•Evolutionary psychologist Martie Haselton foundevidence for a possible adaptation in men to facilitate thesuccess of a short-term mating strategy: an emotional shiftright after sexual intercourseThis work on the attraction-reduction effect supports thehypothesis that men have yet another psychologicaladaptation designed to promote the success of a casualsexual strategy, one that motivates either a hastypostcopulatory departure to minimize investment in anyonewoman or, alternatively, a roving eye within the context of anexisting long-term mateship.
The Closing Time Phenomenon.A related psychological clue to mens strategy ofcasual sex comes from studies that examine shifts injudgments of attractiveness over them course of an eveningat singles barsIn one study, 137 men and 80 women in a bar wereapproached at 9:00 P.M., 10:30 P.M., and 12:00 A.M. andasked to rate the attractiveness of members of the oppositesex in the bar using a ten-point scale.The average judgment at 9:00 was 5.5, but by midnight it hadincreased to over6.5.
Mens shift in perceptions of attractiveness near closing timeoccurs regardless of how much alcohol they have consumedThe often noted "beer goggles" phenomenon, wherebywomen are presumed to be viewed as more attractivewith mens increasing intoxication, may instead beattributable to a psychological mechanism that is sensitiveto decreasing opportunities over the course of the eveningfor casual sex.As the evening progresses and a man has not yet beensuccessful in picking up a woman, he views the remainingwomen in the bar as increasingly attractive, a shift that willpresumably increase his attempts to solicit sex from thosewomen.
Sex Differences in Sexual Fantasies.•Research conducted in Japan, Great Britain, and theUnited States showed that men have roughly twice asmany sexual fantasies as women (Ellis & Symons, 1990;Wilson, 1987)"The most striking feature of [male fantasy] is that sex issheer lust and physical gratification, devoidof encumbering relationships, emotional elaboration,complicated plot lines, flirtation, courtship, andextended foreplay" (Ellis & Symons, 1990, p. 544)
Sexual RegretMen regretted acts of sexual omission-failures to act onsexual opportunities-significantly more than didwomen.Women were more likely to have regretted action ofsexual commission wishing that they had not had sexwith someone that they did have sex with (Poore et aI.,2005)
Evidence for Womens Short-Term MatingIf ancestral women never engaged in short-termmating, men could not have evolved a powerful desirefor sexual varietyOrgasm in Women-Once it was thought that a womansorgasm functioned to make her sleepy and keep herreclined, thereby decreasing the likelihood that spermwould flow out and increasing the likelihood she wouldconceive.
Rather, there is no link between the timing of theflowback and the number of sperm retainedWomen discharge roughly 35 percent of sperm withinthirty minutes of the time of insemination, averagedacross all instances of intercourse. If the woman has anorgasm, however, she retains 70 percent of thesperm, ejecting only 30 percent.
The number of sperm a woman retains is also linkedwith whether she is having an affair.In a nationwide sex survey of 3,679 women in Britain, allwomen recorded their menstrual cycles as well as thetiming of their copulations with their husbands and,if they were having affairs, with their lovers.It turned out that women having affairs appeared totime their copulations, most likely unconsciously, tocoincide with the point in their menstrual cycle whenthey were most likely to be ovulating and hence weremost likely to conceive (Baker & Bellis, 1995)
Behavioral Evidence of Extramarital Affairs.The behavioral evidence also suggests that women in allbut the most restrictive societies sometimes engage inextramarital sexual unions.
Resource Hypotheses--Women could engage in short-term mating in exchange for meat, goods, or services.•Another possible resource is protection•Smith (1984) proposed the status enhancementhypothesis of short -term mating.
Genetic Benefit Hypotheses•enhanced fertility•a short-term mate might provide superior genes•short-term mate might provide a woman with differentgenes compared with those of her regular mate, thusenhancing the genetic diversity of her children-perhapsa hedge against environmental change (Smith, 1984).
Mate Switching Hypotheses•Sometimes a womans husband stops bringing inresources, starts abusing her or her children, orotherwise declines in his value to her as a mate•According to the mate expulsion hypothesis, having ashort-term affair would help the woman to get rid of herlong-term mate. Because men in many cultures oftendivorce wives who have affairs (Betzig, 1989), having anaffair would be an effective means for the woman toinitiate a breakup.
Short-Term for Long-Term Goals•Another hypothesis is that women use short-termmating as a means to assess and evaluate prospectivelong-term mates (Buss & Schmitt, 1993).•Engaging in short-term mating allows a woman toclarify the qualities she desires in a long-term mate,evaluate her compatibility with a particular man (e.g.,sexual compatibility), and reveal any hidden costs hemight carry (e.g., existing children, deception)
Mate Manipulation Hypotheses•By having an affair, a woman might be able to gainrevenge on her husband for hisinfidelity, thus possiblydeterring him from future infidelities (Symonds, 1979)•A woman might be able to increase the commitment ofher regular mate if he saw with stark evidence thatother men were seriously interested in her (Greiling &Buss, 2000).
•Women risk impairing their desirability as a long-termmate if they develop reputations for promiscuousness,because men prize fidelity in potential wives•Lacking a long-term mate to offer physical protection,a woman who adopts an exclusively short-term sexualstrategy is at greater risk of physical and sexual abuse.
•The unmarried woman in the pursuit of casual sexrisks getting pregnant and bearing children without thebenefit of an investing man.•An unfaithful married woman risks the withdrawal ofresources by her husband.•women risk contracting sexually transmitted diseasesfrom short-term mating-a risk that is greater for womenthan for men per act of sex (Symons, 1993)
•Several researchers have discovered that the womanwho is engaged in short-term mating places a premiumon the mans physical attractiveness, a findingconsistent with the good genes and the sexy sonhypotheses (Buss & Schmitt, 1993; Gangestad &Simpson, 1990; Kenrick et aI., 1990)
Several studies have found that women who have affairsare significantly less happy with their currentpartner, emotionally and sexually, than women who donot (Glass & Wright, 1985; Kinsey et aI., 1953). Thisprovides circumstantial support for the mate switchinghypothesis.
Hypotheses Supported: Mate Switching, MateExpulsion, and Resources.Hypothesis That Is Promising: Short-Term forLong-Term Goals.