Human Stereotypes Are True in Social, Sexual Behavior

Sept. 30, 1998
Contact: Christian Basi, Sr. Information Specialist
(573) 882-4430, [email protected]

HUMAN STEREOTYPES ARE TRUE IN SOCIAL, SEXUAL BEHAVIOR, SAYS MU RESEARCHER

COLUMBIA, Mo.-- "Men never do any of the work around the house; they never help with raising the kids!" "Women cry too much; they're too emotional!" "Why do boys always roughhouse; they compete over everything." "Girls always sit around and play with their dolls, and teenage girls always talk on the phone and gossip."

Sound familiar? It should, because it's true according to David Geary, professor of psychology at the University of Missouri-Columbia and author of the new book Male, Female: The Evolution of Human Sex Differences. Following 18 months of research and a review of more than 1,200 studies in the areas of psychology, biology and anthropology, Geary concluded that these stereotypes are true and strongly influenced by nature, especially the strategies humans develop and use to attract mates and compete with members of the same sex.

"These findings may not sit well with some people, but after this extensive review of studies, we found that many stereotypes are true," Geary said. "Over the course of evolution, these stereotypes have resulted due to strategies used by males and females to attract mates. Men and women use certain sexual strategies in order to reproduce, and they are essential to our mating patterns."

According to Geary, the different sexual strategies that men and women use in their drive to reproduce are the true cause of many stereotypical sex differences such as physical attributes and physical development, play patterns, social behavior and social development, parenting interests, motivational and emotional patterns, cognitive abilities, and brain structure and functions. Geary's research provides a description of all these sex differences and explains how and why they are ultimately related to the different strategies women and men use to reproduce.

"It is not simply that 'men want sex' and 'women want babies,'" Geary said. "Men invest more in the well-being of their children than do the males of our closest relatives, chimpanzees and bonobos. Nature prompts men to invest in babies too, but not as much as women. When they invest in babies, men become an important resource to women, a resource that women compete over, sometimes physically. At the same time, investing in babies makes men almost as picky as women when it comes to choosing a spouse, although much less picky when it comes to casual sexual partners."

Geary takes these basic patterns and explains how they are expressed in different cultures and during different historical periods within the same culture. Men all over the world

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compete for social dominance and cultural success, but the ways they compete varies from one culture or historical period to the next. In some cultures, success is defined by how many men a prospective mate has murdered. In other cultures, success is defined by earning an MBA and having a good income. The dynamics are the same, however. Men who achieve cultural success have more mating opportunities and, in most cultures, more children.

"Here we have two strategies of human behavior that have developed into stereotypes over the course of time," Geary said. "Females are mating with males who have cultural success, or money in most cases, and males are competing for that cultural success so, as a result, they stay away from the home more and have less to do with raising the children."

Geary's research also concluded that these stereotypes are evident very early in life. Childhood is the time to practice and refine the social and sexual strategies that will be used in adulthood. Boys, for instance, engage in rough and tumble play and competitive sports much more than girls because this prepares them for later competition with other males.

Girls and women also compete, but in a different way. Research showed that girls and women gossip, back bite, spread rumors about and shun potential competitors. For girls this is practice for later competition over husbands, using it to exclude competitors from a social group and thus make them unavailable as mating partners to the men they are trying to attract. Girls also practice play parenting more often than boys because as adults they invest more in the well-being of their children than their husbands, a pattern that has been true for the most part throughout human evolution, Geary said.

"Girls play with dolls much more than boys, and it has nothing to do with Barbie, television ads or gender stereotypes and has everything to do with human nature and the best interests of women," Geary said. "Men invest in children about one-third as much as women--a sex difference found in every culture in which it has been studied. This sex difference is in fact found in most primates. In these species, females who play parent have more surviving offspring than females who do not play parent." Geary said that the same pattern was found consistently throughout human evolution and thus the real source of the current sex difference in doll play.

Geary also states that many other stereotypes that are found in modern society are indirectly related to our evolutionary history, including sex differences in academic competencies (e.g., girls and women favor reading), violence and accidental death rates (more frequent in boys and men), anxiety and depression (more frequent in women), eating disorders (more frequent in women), occupational status (higher in men) and occupational choices, among other things.

The book is being published by the American Psychological Association, who is calling it the best book it has ever published. The book is available today.

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MALE, FEMALE: The Evolution of Human Sex Differences

A few examples of human behavior and human sex differences that reflect nature

Direct relations ï In 97 percent of mammalian species, males have nothing to do with offspring; humans are an important exception.

ï Men's reproductive behavior can be focused on sex (getting a lot of mates) or on children, depending on ecological (e.g., availability of food) and social (e.g., availability of mates) conditions.

ï Social rules for marriage greatly influence men's reproductive behavior, on average. When having more than one wife is allowed, as it is in 85 percent of human cultures, men focus on marrying as many women as they can. This is typically achieved through intense male-male competition and is associated with high mortality rates in men. When polygyny is illegal, as it is in Western nations, men focus more on raising children than on finding mates, on average.

ï Across cultures, men on average spend about one-third as much time with children as do women.

ï In all societies, women prefer culturally successful men as mating and marriage partners, whether cultural success is defined by income, having murdered competitors or having control over land and cattle.

ï Women also prefer men who are taller than average, athletic (but not too muscular), and have masculine and symmetrical faces. These men are physically healthier than their peers and are therefore likely to sire healthier children.

ï Boys engage in rough and tumble play and play fighting more than girls in all cultures in which it has been studied; girls, however, do sometimes engage in physically competitive activities. This play fighting is a preparation for one-on-one and coalition-based male-male competition, as is found in many preindustrial societies today.

ï In many preindustrial societies, male-male competition is (or was prior to Western intervention) a deadly business, with 30 percent of men dying, on average, as a result of this competition. Men compete this intensely because the winners have more wives and children. The same pattern is found in our closest relative, the chimpanzee.

ï Play parenting, or doll play, by girls is found in all societies in which it has been studied. In societies without Barbie or other dolls, girls use melons, shoes or whatever as child substitutes. This is practice for later parenting.

ï Women are sometimes just as nasty and competitive as men, but not physically. They lie to, back bite, spread rumors about and shun other women who are potential sexual competitors (over husbands).

ï Sometimes it is in women's best interest to have many sexual partners, getting some resources from each, and other times it is in women's best interest to be monogamous and faithful to one man. The former is common in situations where many men are poor and thus don't have the resources to invest in a family. The latter is common where women are married to attractive and socially and economically successful men. -more-

Indirect Relations

ï Girls and women are better at language skills than boys and men because this is how they compete with each other (e.g., gossiping, back biting, etc.). One indirect effect is that girls and women have an advantage over boys and men in language-related academic domains such as reading, writing and spelling.

ï Men have better 3-D spatial abilities than women, because they have more frequently navigated in unfamiliar environments (e.g., hunting, war parties) than women. As a result, boys and men have an advantage over girls and women in some mathematical domains (e.g., geometry).

ï There are no sex differences in IQ, but men are more varied. There are more men at the top and bottom than there are women. Greater variability is common in males, across species, and appears to reflect a greater sensitivity of males than females to environmental conditions. When things go well (e.g. good nutrition, stable social environment), boys seem to benefit more than girls. When things go poorly (e.g., poor nutrition, social conflict), boys suffer more than girls. The net result is greater variability among boys and men than among girls and women in many areas, including IQ.

ï Boys and men engage in riskier activities than girls and women, and as a result they are hurt and killed more frequently than girls and women. They also risk more on the stock market and thus accumulate more wealth. The sex difference in risk taking is directly related to the status-seeking strategy of boys and men: successful risk takers achieve cultural and social success.

ï Anxiety and depression are more frequent in girls and women than boys and men, in part because of how girls and women compete (e.g., through shunning). Girls and women also are more sensitive to social relationships than boys and men and thus feel more anxiety and depression when their social network is disrupted (e.g., a friend is distressed).

ï Anxiety and depression are higher in women with young children than in other women, in part because they fear abandonment by their husbands. Women want husbands to help them raise their children, but sometimes husbands invest their time and energy in finding other mates.

ï Eating disorders in girls and women reflect a combination of men's preferences for thin mates and female-female competition. Women believe that men prefer very thin women, when in fact men prefer more average, but still "thin" women. Eating disorders reflect, in part, a competition for the attention of men, but a distortion of what men really prefer (i.e., women believe men prefer thinner women than is actually the case).

ï The glass ceiling does not fully explain why men earn more money and achieve higher occupational success, on average, than equally capable women. Men are more willing to take risks and sacrifice friends and family to achieve occupational success. This is simply a reflection of the sex difference in striving for cultural success, which, when achieved makes men more attractive marriage and mating partners.

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