David Geary Ph.D.

Male, Female


Sex Differences in Children’s Play

Boys will be boys... or will they?

Posted Oct 15, 2019

Source: 5712495/Pixabay

There is a widespread belief that children’s play activities and toy preferences (e.g., dolls, toy guns) are driven by parents and other social influences (e.g., media), as if children don’t have their own preferences and cannot determine for themselves what they find interesting and what just doesn’t capture their attention. The basic argument is illustrated by Dinella and Weisgram’s (2018) summary of a series of articles on the relationship between parents’ gender schemas (beliefs about girl-typical and boy-typical activities) and their children’s toy preferences:

"We gather together cutting-edge research on the factors that affect gender differences in children’s toy interests, how subtle gender-related messages affect children’s performance and behaviors, and how adults create these gender-related messages and affect children’s interests" (Dinella & Weisgram, 2018, p. 253).

To be sure, there is a relationship between parental attitudes, stereotypes, and prejudices and those of their children, in keeping with a social influence on children’s beliefs and attitudes. The associated meta-analysis by Tenenbaum and Leaper (2002) focused specifically on sex-related stereotypes and included results from 43 studies and more than 10,000 people. They found a modest relation between parent’s stereotyped beliefs and their own children’s stereotyped beliefs about men and women and boys and girls.

The results were primarily for attitudes and did not extend to sex-typed interests and behaviors. The latter includes toy preferences, and here “parents’ gender schemas had a negligible association with children’s gender-related interests” (Tenenbaum & Leaper, 2002, p. 626). In other words, parents have an influence (though still modest) on what children think about what’s “appropriate” for girls and boys, and not as much of an influence on how they actually play or engage with their friends.

From a deeper, evolutionary perspective, we see that play, in one form or another, is found in many mammalian species and in some species of bird, fish, reptile, and invertebrate. Across species, play is a) voluntary, b) not immediately functional, c) involves some components—though muted, exaggerated, or incomplete–of more functional activities (e.g., prey capture), d) is repeated and pleasurable, and e) occurs only in safe environments.

The extent to which play involves the practice and refinement of skills, including the development of social relationships, that will be used in adulthood or is a way to maintain them until adulthood is debated, but it is nevertheless clear that play is an important part of typical, species-specific development. There are several different categories of play, but we’ll focus here on the rough-and-tumble play or play fighting and associated sex differences.

Across species, play fighting includes many of the same behavioral components as intrasexual (within the same sex) fighting or territorial defense but differs in enough ways to make a straight-forward practice of fighting behaviors unlikely. In fact, many of the basic behavioral components of species-specific fighting are evident at birth, but their expression is often better controlled, more nuanced, and more varied for individuals that have engaged in play fighting. By enabling the development of better controlled and more flexible fighting skills, this form of play likely results in improved social competencies and later social-competitive advantage, as well as establishing dominance relationships before play merges into potentially harmful fighting.

Sex differences in play fighting are common and track sex differences in the form and intensity of competition for mates in adulthood or competition for other resources (e.g., food). Sex differences in play fighting tend to be the largest in young males of polygynous species with intense, physical, male-male competition in adulthood, which includes people [see my earlier post, "Men’s Struggle for Status and Relevance"].

Accordingly, play fighting typically occurs more frequently, with more vigor, and with greater zest among boys than among girls. The sex difference is found in all developed nations in which it has been systematically studied, but has not been as systematically studied in traditional cultures. In these cultures, the same-sex difference is generally but not always found.

The lack of sex differences in some contexts is not surprising, because its expression is highly dependent on social context and is most evident with groups of three or more same-sex children and in the absence of adult supervision. The highest rates of play fighting occur in groups of unsupervised children and in safe contexts, where boys engage in various forms of playful physical assaults and wrestling 3 to 6 times more frequently than do same-age girls.

In an analysis of the activities of triads of 4-year-olds, DiPietro (1981) found that boys engaged in playful hitting, pushing, and tripping four and a half times more frequently than did girls. The sex difference in play fighting emerges by age 3 years and peaks between the ages of 8 and 10 years, at which time boys spend about 10 percent of their free time in these activities. As with other mammals in which it occurs, play fighting begins to merge into real fighting during adolescence, and boys who emerge as dominant during these encounters are more attractive to adolescent girls.

As I described in a previous post ["Men’s Struggle for Status and Relevance"], male-male competition in many traditional contexts and for much of human evolution often occurs between groups, as well as within them. The sex difference in the bias to self-organize into large and competing groups is illustrated by Lever’s (1978) study of children’s play and engagement in games. She asked 181 10- and 11-year-olds to record their after-school activities during the course of one week, resulting in 895 cases of social play.

During this week, boys participated in group-level competitive activities, such as football and basketball, three times as frequently as did girls. Observation of these children’s spontaneous (i.e., not organized by adults) play activities confirmed the pattern noted in their diaries and indicated that boys’ social play involves larger groups and greater role differentiation within these groups.

"More often, boys compete as members of teams and must simultaneously coordinate their actions with those of their teammates while taking into account the action and strategies of their opponents. Boys interviewed expressed finding gratification in acting as a representative of a collectivity; the approval or disapproval of one’s teammates accentuates the importance of contributing to a group victory" (Lever, 1978, p. 478).

In short, when left to their own devices, children engage in activities and organize themselves in ways that are consistent with aspects of our evolutionary history. This does not, however, mean that parents or other adults have no influence or that there are no wider cultural influences. For instance, the intensity and nature (e.g., use of toy weapons) of boys’ play fighting varies with the intensity of physical male-male competition–especially between-group warfare–in their social world.

In societies characterized by high levels of male-on-male physical aggression among adults, the play fighting of boys is rougher than the play fighting in more peaceful societies. In former societies, parents and other adults encourage engagement in play fighting and sometimes organize rough and physically demanding games to better prepare boys for the rigors of adulthood. In more peaceful societies, parents tend to discourage and actively suppress roughhousing.


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