A very recent paper in Biology Letters (Durante & Li cited below) reports that the level of certain female hormones, in this case, estradiol (American spelling) appears to influence the propensity of women to mate “opportunistically.”
That last phrase, “mate opportunistically,” is becoming an established term in a field with increasing scientific validity called evolutionary psychology.
Despite the use of the term “psychology,” the overall field has considerable participation from researchers in clinical medicine ( particularly those in endocrinology, medical genetics, and obstetrics/gynecology), and by basic scientists in the fields of sensory physiology and physical anthropology.
It should be stated outright that the vast bulk of studies deal with heterosexual attractions and relationships, and moreover, the researchers neither make value judgments on personal choices among consenting adults nor do they condone or advocate behavior that is unlawful or known to be detrimental to children.
Women’s Preferences in Male Mates According to Contemporary Studies in Evolutionary Psychology
Study and research in evolutionary psychology involves many different topical subdivisions, but this blog will focus on what the field itself calls “reproductive strategies.”
A core question is: What do women, consciously or unconsciously, look for in mates, and when do they do that looking most intensely?
Evolutionary psychology basically posits that despite whatever overt and intellectually well-though-out statements given by even highly educated women upon being interviewed, of what they seek in male sexual partners (at least in economically developed Western societies in North & South America, Europe, Australia, New Zealand and the more prosperous parts of Asia), underlying biological urges that have been encoded as offspring survival genes govern their reproductive behavior and probably actually drive who and what arouses them and when.
Hormones & Assessments of Attractiveness
There are a plethora of studies (many of them cited below) that show a very strong connection between hormone levels in the sexual behaviors of both women and men.
Probably the most striking finding is that each gender is a pretty good if unconscious estimator of the times of the month when women of reproductive age seem to be most interested in sexual activity.
The levels of certain hormones, particularly estradiol and somewhat surprisingly testosterone, in women make those women feel more attractive and sexually aroused, not only in their own judgment of themselves, but among their fellow women’s judgment of them, and especially in how the aroused women estimate that men will be attracted to them, as compared to mens’ attraction at those times when their hormone levels are not so high.
This persistent finding has been confirmed through a wide variety of means of measuring both the hormone levels of women being studied, and interviewing the same women about their own desirability and attractiveness , and interviewing and videotaping women making desirability or attractiveness judgments about other women, and men making judgments about the same women. There is a surprising degree of concordance among all these groups.
Given that most women do not carry a hormone meter to estimate the levels in themselves, in other women, or even in men, and therefore cannot be consciously, cognitively certain of them, how do they unconsciously project and self-rate their relative attractiveness and arousability?
Frankly, they do so by looking at their own faces and bodies, which turns out to be the same way other women and men unconsciously gauge them. Ratings of the facial attractiveness of women at, or near, peak monthly fertility are actually higher than ratings of the same faces at other phases of the month. In addition, their own unconscious scanning of desirable males kicks into high gear, and their preferences for differing types of male shifts, often dramatically, if only temporarily.
Short-Term Sex Partners Versus Long-Term Mates
Most of these studies and arguments concerning sexual behavior from the viewpoint of evolutionary psychology and the strong effects of hormones and acquiring good genes for their children, would be of perhaps academic interest only, if they did not have, in fact, real life consequences and strong explanatory power for actual behaviors.
There is ample medical evidence through the analysis of DNA records of children and parents in economically advanced countries, ironically often undertaken for reasons apart from legal determinations of paternity, most commonly for testing for inherited diseases, that the apparent father, that is, the man who thinks, acts, and financially and emotionally supports a child, as if he is surely the parent of that particular child, is not in fact, the biological father.
This excludes children who are adopted or children who are the result of known prior relationships.
A meta-analysis of 17 studies by Bellis et al (cited below) indicates that the range is somewhere between eight-tenths of one percent and thirty percent, but is overall around three children out of 100, with variations understandably based on local culture, economic and social mores.
Evolutionary psychology tends to explain this surreptitious mating on the woman’s part by a short-term shift of interest in, and visceral need for, really “masculine” appearing men, who figuratively (and according to some studies physiologically) exude the air of dominance over other men, even if this is not the woman’s overtly stated preference, or even their unconscious preference for most of the rest of the month.
For the sake of imagery, women who feel themselves to be at the highest level of sexual attractiveness and willingness to have sex are always going to pick a Tony Soprano (as opposed to say, a Tony Stankus) because he is seen as the ultimate alpha male.
Evolutionary psychologists suggests that this goes back to females seeking the very strongest male among a clan to father their children so that the resulting children would be more likely to be strong owing to the father’s genes for size, vigor and strength.
Under the strong man-good genes strategy, both mother and children would ideally be better protected, and better provided with resources, because potentially, the putative father becomes emotionally invested in them to boot, and in particular defend them against any aggressive males who intend them harm.
Men reciprocate this attraction by unconsciously or otherwise seeking out women who appear to be more confident about their own sexual attractiveness. They are primed for this partly by their own raised levels of testosterone, and the presence of attractive women raises the boldness of their attempts to seek opportunities to have sex with these women, at least in part because the women’s mere presence, and the women’s both conscious and unconscious behavior towards those men, increases the men’s testosterone levels.
Videotaped studies show that women in such situations will flirt more often and more aggressively, even if they are unaware that they are doing so.
Pheromones, Attractiveness & Arousability
One area of ongoing controversy is whether or not men (or women) give off sexually exciting pheromones that unconsciously stimultate women to take a higher interest in having sex with them.
The preponderance of evidence say yes, but this has not yet resulted in after-shaves or colognes for men (or women) that claim to have pheromones that demonstrably accomplish this mission, despite advertising claims to the contrary.
One of the very most intriguing studies shows that when a male experimenter conducts a surreptitious test (meaning that no odor can be detected at the conscious level) of male-derived sexually attractive odorants among heterosexual women, results will indicate an increase in the mood or state of sexual arousal of the women subjects, as opposed to having a female experimenter perform the same experiment with the same tiny dosage of pheromone.
The most important finding here is not that the sexually arousing odorant is somehow fake or ineffective, because theoretically it should work the same despite the gender of the experimenter, but rather that the presence of the male potentiates the susceptibility of the women to the odorant’s arousing effect.
Ironically, the source of the male pheromones that appear to result in the greatest arousal on the part of women in serious scientific tests, comes from the armpit sweat of men, although armpit-sweat-smelling aftershaves and colognes seem not likely to find a successful market, for some strange reason.
Of course, pheromones and the primitive drive of having the alpha-male in the room be your sex partner in order to have optimal progeny are by no means the only factors that govern women’s attractiveness for men of a given type at times of their peak fertility.
Well educated women in economically advanced countries also prefer men who are bosses in their company or organization, as opposed to being mere staff employees. They prefer taller men as opposed to shorter men. They prefer more educated men as opposed to less educated men, and in particular, they prefer wealthier men to men or lesser means.
Evolutionary psychologists explain these preferences in the context of their being more modern proxies for evidence of dominance and virility. Unconsciously, these men appear to have the right genes to pass on to have kids who turn out to be more competitive in the modern world.
But this does not always lead to instant switching of partners in today's world.
Studies in social psychology show that highly attractive higher-status females are more likely to abandon a financially or otherwise underpeforming male partner before regularly having sex with a more successful male that she has since identified as more to her liking using criteria that grow more stringent with her own rise in power and self-esteem. The higher the achievement of the female, the more likely it seems that serial monogamy, rather than surreptitious flings will result.
Is There A Time When the Slow & Steady Nice Guy Wins Out In Ratings of Attractiveness by Females?
Do women’s stated or unconscious preferences for men of a given type change when they are not at peak fertility?
The preponderance of evidence suggests that they do.
Curiously, their preference for men in their ratings of facial attractiveness indicates that when they are not at the most fertile peak, and in fact when they are at their highest level of progesterone, and essentially feeling the most ordinary and normal (as it were) they drop their preference for pictures of tough-guy, hypermasculine men, and go for images of men that have been computer “feminized.”
The evolutionary psychology of this phenomenon is that such men would be better long-term nurturers, even if they were not the actual fathers.
Unfortunately for such men, some studies are showing that hypermasculine men who also show an interest to attractive and fertile females in fathering their babies (which does not necessarily mean that they are equally interested nurturing them in the long run) are more likely to be successful in having sex with these females, resulting in what evolutionary psychologists call an increasing number of cases of “paternal discrepancy”.
In other words, the mild-mannered steady guy has much more risk of raising some alpha male’s child unawares, because this evolutionary combination yields the best of both worlds for the mother and the child, because the short-term acquisition of the strongman genes by the mother and the long-term partnering in the good nurturing of the child, are both more reliably obtainable through this subterfuge.
Of course, this has the propensity of mild-mannered men raising alpha-male sons who are more likely to sense the discordant paternity, and ironically the sons may end up having the evolutionary psychology that makes them identify and behave like their biological fathers, in dominating mild-mannered males, perhaps including their own fathers.
Men Are So Obvious in What Attracts Them! (But They Often Agree With Women in Ratings of Attractiveness)
To the surprise of some, men and women have fundamentally the same preferences and propensities in rating women’s faces as attractive. Symmetry of facial features and a certain proportionality among them is highly valued.
Curiously men and women also tend to agree, in part, on what constitutes an attractive body.
Both rate those women more highly who have a ratio in which the waist is significantly narrower than the hips, even though the absolute measurements may be larger or smaller in different cultures. In other words, you could have a twenty four inch waist, or a thirty inch waist, and the key is that your hips ought to be proportionally larger, up to a point.
This almost universal preference low waist-to-hip ratio seems to fly in the face of arguments that would suggest that women with large amounts of body fat around their stomach, would have ample stores of energy that would ensure better the survival of the children that she would nurse, particularly in times of food scarcity.
Therefore you would think that evolutionary theory would predict that these fat women would seem to be preferred partners for virile males who seek to have many healthy offspring.
But except for isolated cultures, obese women are not rated very highly in scales of attractiveness by either men or women.
For what it is worth, the same is increasingly true on ratings the sexual attractiveness of obese men.
Only smokers now do worse than fat people of either of either gender in polling.
However, evolutionary psychology now suggests that modern medical thinking on abdominal obesity as posing a multitude of serious health risks for the woman, and therefore burdens on the male and on the children, seems to have already been encoded genetically over the course of human evolution.
In other words, a chronically sick female is optimal for neither the male nor the offspring, and genes that lead to that adverse body type will be ultimately selected against.
What is the dominant physical trait that men in Western cultures seek after an acceptable waist-to-hip ratio?
Well, it’s breast size, of course.
Apart from East Asia, which has an outright revulsion to the notion of large breasts as being attractive features (Barbie dolls have to be modified in order to sell successfully there), large, and prominently projecting breasts are the premier runaway (if not fashion model runway) successes as male attractants.
Two studies are particularly illuminating, if not surprising. In a pair of serious scientific studies by Gueguen (cited below), videotapes of women in which they wore the same outfits, but had bras that allowed them progressively to increase their bust size, experienced more men “hitting on them” in night clubs and actually had more male (but not female) car drivers pick them up when they were hitchhiking, when they displayed the larger breasts versus the smaller ones.
(Hitchhiking in Europe is a far safer, more common, and even socially promoted practice, particularly for teens and the 20 year old confederate who was used in the study.)
Evolutionary psychology suggests that this is owing to large breasts being a good advertisement for healthy nutritional status, optimal reproductive potential, and overall good health, a finding, that while unpopular in some quarters, I’m sure, actually appears true in modern medicine and recent studies of physical anthropology. (see Jasienska et al, cited below).
But in any case, evolutionary psychology is not as much destiny as unconscious reproductive propensity, and it is scarcely infallible. If it were, would not everyone who is reading this blog with eyeglasses or contact lenses not be here, owing to genes for bad eyesight?
Tony Stankus [email protected] Life Sciences Librarian & Professor
University of Arkansas Libraries MULN 223E
365 North McIlroy Avenue
Fayetteville, AR 72701-4002
Bellis, M.A., Hughes, K., Hughes, S. & Ashton, J.R. (2005). Measuring paternal discrepancy and its public health consequences. Journal of Epidemiology and Community Health, 59 (9), 749-754.
Brody, S. (2004). Slimness is associated with greater intercourse and lesser masturbation frequency. Journal of Sex & Marital Therapy, 30(4), 251-261.
Brown, W.M., Price, M.E., Kang, J., Pound, N. Zhao, Y. & Yu, H. (2008). Fluctuating asymmetry and preference for sex-typical bodily characteristics. Proceedings of the National Academy of Sciences USA, 105, (35), 12938-12943.
Cutler, W.B. & Genovese-Stone, E. (1998). Wellness in women after years of age: The role of sex hormones and pheromones. Disease of the Month, 44, (9), 421-546.
Buss, D. M. (2002). Human mate guarding. Neuro Endocrinology Letters, 23 Suppl 4, 23-29.
Danel, D. & Pawlowski, B. (2007). Eye-mouth-eye angle as a good indicator of face masculinization, asymmetry, and attractiveness (Homo sapiens). Journal of Comparative Psychology 121, (2): 221-225.
Danel, D. & Pawlowski, B. (2006). Attractiveness of men’s faces in relation to women’s phases of menstrual cycle. Collegium Anthropologicum, 30, (2), 285-289.
Davidson, M., & Knafl, K. A. (2006). Dimensional analysis of the concept of obesity. Journal of Advanced Nursing, 54(3), 342-350.
Durante, K.M. & Li, NP. L. (2009). Oestradiol level and opportunistic mating in women. Biology Letters epub ahead of print. doi: 10.1098/rsbl.2008.0709.
Fineman, J. (1977). Fratricide and cuckoldry: Shakespeare's doubles. Psychoanalytic Review, 64(3), 409-453.
Gangestad, S. W., & Cousins, A. J. (2001). Adaptive design, female mate preferences, and shifts across the menstrual cycle. Annual Review of Sex Research, 12, 145-185.
Gangestad, S. W., Garver-Apgar, C. E., Simpson, J. A., & Cousins, A. J. (2007). Changes in women's mate preferences across the ovulatory cycle. Journal of Personality and Social Psychology, 92(1), 151-163.
Gangestad, S. W., Simpson, J. A., Cousins, A. J., Garver-Apgar, C. E., & Christensen, P. N. (2004). Women's preferences for male behavioral displays change across the menstrual cycle. Psychological Science, 15(3), 203-207.
Gopal, R. L., Beaver, K., Barnett, T., & Ismail, N. S. (2005). A comparison of the information needs of women newly diagnosed with breast cancer in Malaysia and the United Kingdom. Cancer Nursing, 28(2), 132-140.
Gueguen, N. (2007). Women's bust size and men's courtship solicitation. Body Image, 4(4), 386-390.
Gueguen, N. (2007). Bust size and hitchhiking: A field study. Perception and Motor Skills, 105, (3, part 2), 1294-1298.
Harris, C. R. (2000). Psychophysiological responses to imagined infidelity: The specific innate modular view of jealousy reconsidered. Journal of Personality and Social Psychology, 78(6), 1082-1091.
Harris, C. R. (2002). Sexual and romantic jealousy in heterosexual and homosexual adults. Psychological Science, 13(1), 7-12.
Harris, C. R. (2003). A review of sex differences in sexual jealousy, including self-report data, psychophysiological responses, interpersonal violence, and morbid jealousy. Personality and Social Psychology Review 7(2), 102-128.
Harvey, E. L., & Hill, A. J. (2001). Health professionals' views of overweight people and smokers. International Journal of Obesity and Related Metabolic Disorders 25(8), 1253-1261.
Harvey, E. L., Summerbell, C. D., Kirk, S. F., & Hill, A. J. (2002). Dietitians' views of overweight and obese people and reported management practices. Journal of Human Nutrition and Dietetics 15(5), 331-347.
Husarova, B. (2005). Adaptive mating strategies and the problem of mate retention. Anthropologischer Anzeiger 63(3), 283-287.
Jasiesnska, G., Ziomkiewicz, A., Ellison, Peter T., Lipson, S. & Thune, I. (2004), Large breasts and narrow waists indicate high reproductive potential in women. Proceedings of the Royal Society of London B – Biological Sciences, 271, 1213-1217.
Jones, B. C., DeBruine, L. M., Perrett, D. I., Little, A. C., Feinberg, D. R., & Law Smith, M. J. (2008). Effects of menstrual cycle phase on face preferences. Archives of Sexual Behavior, 37(1), 78-84.
Jones, B.C., Little, A.C., Boothroyd, L. and others. (2005). Commitment to relationships and preferences for femininity and apparent health in faces are strongest on days of the menstrual cycle when progesterone level is high. Hormones & Behavior, 48, (3), 283-290.
Kornblau, I.S., Pearson, H.C. & Breitkopf, C.R. (2007). Demographic, behavioral, and physical correlates of body esteem among low-income female adolescents. Journal of Adolescent Health, 41 (6): 566-570.
Leon, G. R., Eckert, E. D., Teed, D., & Buchwald, H. (1979). Changes in body image and other psychological factors after intestinal bypass surgery for massive obesity. Journal of Behavioral Medicine, 2(1), 39-55.
Lundstrom, J.N., & Olsson, M.J. (2005). Subthreshold amounts of social odorant affect mood, but not behavior, in heterosexual women when tested by a male, but not a female , experimenter. Biological Psychiatry, 70 (3), 197-204.
Nagelkerke, N. J., Bernsen, R. M., Sgaier, S. K., & Jha, P. (2006). Body mass index, sexual behaviour, and sexually transmitted infections: An analysis using the NHANES 1999-2000 data. BMC Public Health, 6, 199.
Nakdimen, K.A. (1984). The physiognomic basis of sexual stereotyping. American Journal of Psychiatry, 141, (4), 499-503.
Rhodes, G., Yoshikawa, S., Palermo, R., Simmons, L.W., Peters, M., Lee, K., Halberstadt, J. & Crawford, J.R. (2007). Perceived health contributes to the attractiveness of facial symmetery, averageness, and sexual dimorphism. Perception, 36, (4), 1244-1252.
Roney, J.R., Hanson, K.N., Durante, K.M. & Maestripieri, D. (2006). Reading men’s faces: Women’s mate attractiveness judgements track men’s testosterone and interest in infants. Proceedings of the Royal Society of London B – Biological Sciences, 273, (1598), 2169-2175.
Singh, D. 2004. Mating strategies of young women: Role of physical attractiveness. Journal of Sex Research, 41 (1), 43-54.
Singh, D., Renn, P. & Singh, A. (2007). Did the perils of abdominal obesity affect depiction of feminine beauty in the sixteenth to eighteenth century British literature? Exploring the health and beauty link. Proceedings of the Royal Society of London B – Biological Sciences, 274 , 891-894.
Swaddle, J.P. & Reierson, G.W. (2002). Testosterone increases perceived dominance but not attractiveness in human males. Proceedings of the Royal Society of London B – Biological Sciences, 269, (1507), 2285-2289.
Thorne, F., Neave, N., Scholey, A., Moss, M. & Fink, B. (2002). Effects of putative male pheromones on female ratings of male attractiveness: Influence of oral contraceptives and the menstrual cycle. NeuroEndocrinology Letters, 23, (4), 291-297.
Tovee, M. J., Reinhardt, S., Emery, J. L., & Cornelissen, P. L. (1998). Optimum body-mass index and maximum sexual attractiveness. Lancet, 352, (9127), 548.
Welling, L. L., Jones, B. C., DeBruine, L. M., Conway, C. A., Law Smith, M. J., Little, A. C., et al. (2007). Raised salivary testosterone in women is associated with increased attraction to masculine faces. Hormones and Behavior, 52(2), 156-161.
Welling, L. L., Jones, B. C., DeBruine, L. M., Smith, F. G., Feinberg, D. R., Little, A. C., et al. (2008). Men report stronger attraction to femininity in women's faces when their testosterone levels are high. Hormones and Behavior, 54(5), 703-708.
Winman, A. 2004. Do perfume additives termed pheromones warrant being termed pheromones. Physiology & Behavior, 82, (4), 697-701.
Zebrowitz, L.A., Olson, K. & Hoffman, K. (1993). Stability of babyfacedness and attractiveness across the lifespan. Journal of Personality and Social Psychology, 64, (3), 453-466.