SEX DIFFERENCES IN CHILDREN'S INVESTMENT IN PEERS

Joyce F. B e n e n s o n , T a m a r a M o r g a n s t e i n , a n d R o s a n n e R o y

McGill University

It is hypothesized from within an evolutionary framework that females should be less invested in peer relations than males. Investment was operationalized as enjoyment in Study I and as preference for interaction in Study 2. In the first study, four- and six-year-old children's enjoyment of peer interaction was observed in 26 groups of same-sex peers. Girls were rated as enjoying their interactions significantly less than boys. In the second study, six- and nine-year-old children were interviewed about the individuals with whom they spend time in their homes and neighborhoods and about the individuals who participate in their favorite activities. The proportion of individuals named by children who were peers was significantly lower for girls than boys both in children's neighborhoods and in children's favorite activities. Results strongly support the hypothesis that females and males have evolved differential preferences for interaction with peers. KEYWORDS: Canada; Children; Peer relations; Sex differences.

Across m a m m a l i a n species, females of all ages h a v e m o r e i n v o l v e d than males in caring for offspring K r a s n e g o r a n d Bridges 1990; M o n e y 1987). In contrast, h a v e b e e n m o r e i n v o l v e d t h a n females in p r o v i d i n g

b e e n f o u n d to be (for reviews, see males universally protection a n d in

Received January 6, 1998; accepted February 12, 1998.

Address all correspondence to Joyce Benenson, Department of Educational and Counselling Psychology, McGill University, 3700 McTavish Street, Montreal, Quebec, Canada H3A 1Y2. E-mail: [email protected] Copyright 9 1998 by Walter de Gruyter, Inc., New York Human Nature, Vol. 9, No. 4, pp. 369-390. 369

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hunting (e.g., Tiger 1969). Evolutionary theorists have long attempted to explain this sexual division of labor (e.g., Darwin 1871; Trivers 1972). Given this division of labor, however, it is reasonable to hypothesize that males' and females' social motives also differ (see also Knight and Kagan 1989). Specifically, a female would most likely benefit from forming bonds with individuals who are most invested in her offspring. Those individuals include the father of her offspring and her own biological relatives, particularly those who are able to help rear her offspring--her mother and younger sisters would be the first choices, with her grandmother, older sisters, aunts, and cousins who have primary ties to other offspring as secondary choices. In contrast, a male would most likely benefit from forming bonds with individuals who are adept at creating organizations strong enough to fight and hunt successfully. These organizations should consist of relatively young males and of a few males who are experienced and have superior knowledge in these areas. Although relatives such as brothers and male cousins might be included, the most successful organizations should consist mainly of unrelated, relatively young peers who are superior in physical strength and are knowledgeable about fighting and hunting. Support for the greater importance of peers in males' versus females' lives is found in studies of non-human primate species. In the majority of primate species, females live in large groups with other female kin and non-kin throughout their lives. The groups contain females of all ages as well as infant males. Within the groups, females cooperate most with their biological relatives (Datta 1992), and then with other females from unrelated matrilines to obtain resources for their offspring and to protect their offspring from aggressive males (e.g., Wrangham 1980). Infants inherit the dominance ranks of their mothers when they are born. Dominance rank determines the infant's access to resources and reduces aggression and competition within the mother's social group. When males become juveniles, however, they leave the female group into which they were born. At that point, they lose their inherited dominance rank, as well as their connection to kin. Juvenile males join with mainly unrelated males of the same age to find other groups to join. Competition and aggression greatly increase, and the most important characteristics for males are not kin, as for females, but age, size, strength, and fighting skill (for a review, see Lee and Johnson 1992). Males who lack these characteristics are not only low in the dominance hierarchy but also have limited access to coalitions with other peers (Hrdy 1981; van Hooff and van Schaik 1992). Those males who band together in large, well-organized groups with other relatively young males are better able than solitary males or males with only a few companions to defend themselves in

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order to gain access to resources and to maintain that access both for themselves and eventually for their mates and offspring. Not all primate species, however, follow the same principles. In human beings' two closest relatives, gorillas and chimpanzees, social organization is different. In gorillas, females generally live in groups of unrelated females of all ages with one dominant male (e.g., Pusey and Packer 1987; Stewart and Harcourt 1987). When a young female matures sexually, she must leave her natal group to avoid mating with the solitary male who is her father. Solitary males continually vie for access to a group of unrelated females. In chimpanzees, the only long-term associations of females are between mothers and infants. Females are otherwise solitary. Males, however, form strong, stable groups usually with relatives (Goodall 1986; Nishida and Hiraiwa-Hasegawa 1987). Thus, not all data support a greater role for peers in males' lives. In all species, however, males and females differ in their attraction to relatives of varying ages versus to unrelated peers. It is unclear which pattern human beings follow. Consistent with findings from the majority of primate species, however, much research with human beings has demonstrated that females of all ages have closer ties to families than do males (for reviews, see Belle 1989; Troll 1987). If sex differences in preferences for familial versus peer relationships have evolved, then they should be apparent as soon as the young begin to socialize and practice their sex roles and should peak when females begin to reproduce and when males are responsible for protecting and procuring food for families. In fact, beginning in the third year of life, children have universally been found to exhibit preferences for play with same-sex peers (for reviews, see Hartup 1983; Maccoby 1988; Maccoby and Jacklin 1987; Whiting and Edwards 1988), a preference that peaks in middle childhood (e.g., Buhrmester and Furman 1987; Feiring and Lewis 1991; Thorne 1986; Whiting and Edwards 1988) but continues into adolescence (e.g., Buhrmester and Furman 1987; Pellegrini 1994). Segregation of social interaction by sex has also been reported in many non-human primate species (e.g., Goodall 1986; Harcourt and de Waal 1992; Harlow and Lauersdorf 1974; Rosenblum et al. 1975). It is reasonable to assume that sexsegregation is at least partially explained by sex differences in interest in raising offspring versus in fighting and hunting. Surprisingly, the large literature on peer relations in middle childhood has rarely analyzed sex differences. Instead, most studies of children's peer relations have either pooled results from both sexes or included only boys (for reviews, see Coie et al. 1990; Newcomb and Bagwell 1995; Newcomb et al. 1993). The few differences that have been reported are that girls are generally more cooperative and nurturant in their peer

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relationships than are boys and that boys generally engage in more rough-and-tumble play and physically aggressive behavior with their peers than do girls (e.g., Cole et al. 1990). No research has examined whether sex differences exist in preferences for peer relationships. This is surprising because research on non-human primates demonstrates a clear sex difference in preference for interaction with peers. Across a variety of studies under both laboratory and naturalistic conditions, after infancy males have been found to spend more time with peers than females, who spend more time in mixed-age groups (e.g., Berman et al. 1994; Biben and Suomi 1993; Goodall 1986; Rosenblum et al. 1975). For example, in a recent study of young free-ranging rhesus monkeys' reactions to their mothers' resumption of mating, young females were found to increase their frequencies of grooming females of mixed ages, whereas young males were found to increase their frequencies of play with peers. The authors concluded that sex differences in social behavior increase "as females become progressively more integrated into the adult female core of the group and as males become gradually more integrated into play relationships with peers and more peripheral from the female core" (Berman et al. 1994:1039). In societies with formal schooling, children are generally divided into age-graded classes, and peers are the only available social partners. This may be the reason researchers have not have been inspired to examine sex differences in preferences for peer relationships. Anthropological studies of cultures without formal schooling, however, suggest that females spend less time than males with peers. Whiting and Edwards (1988), studying several non-western cultures, reported that girls and boys did not differ in the number of individuals with w h o m they spent time. Girls, however, spent more time caring for babies near female adults. In contrast, boys spent more time with peers. Similarly, Wenger (1989), studying a rural community in Kenya, found that beginning at age four years, boys and girls were equally sociable but girls spent more time with infants and adults, whereas boys spent more time with peers. In studies of children's social support figures in western societies, girls have consistently been found to spend more time with family members than boys (e.g., Belle 1987; Feiring and Lewis 1989; for reviews, see Belle 1989; Troll 1987). In preschool and elementary school settings, girls have also been found to spend more time closer to adults than boys (e.g., Huston and Carpenter 1985; Huston et al. 1986). Whether this is due to girls' greater enjoyment of interaction with adults or to other factors, such as girls' greater fearfulness or more restrictions on girls' as opposed to boys' movements, is unknown. In the United States and Sweden, boys have been found to spend more time than girls in formal organizations of peers (Bryant 1985; Tietjen 1982)

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and with more peers at a time (for a review, see Belle 1989). The sexes have not been found to differ, however, in number of same-age friends or acquaintances at any age (e.g., Benenson 1990; Cairns et al. 1985; Feiring and Lewis 1987, 1989, 1991; Fischer and Oliker 1983; Rubin 1985; Walker 1994). The difficulty with most research on peer relations in western societies, however, is that it occurs primarily in schools in which both girls and boys have limited access to individuals other than peers. To date, virtually no research has examined directly whether peer relations are preferred less by girls than boys. An exception is a study by Charlesworth and Dzur (1987) of preschool children in which 20 groups of four same-sex children were videotaped as they played with a movie viewer for 12 minutes. For one child to view the movies, it was necessary for two other children to operate the movie viewer. Boys' and girls' groups did not differ in the amount of time children viewed the movies. Girls, however, displayed significantly less positive affect than boys, suggesting that they enjoyed their peer interactions less than boys. The sex difference may have been due, however, to the competition that was inherent in gaining access to the movie viewer. Alternatively, the boys may have been rated as enjoying the film more than the girls, because boys may generally laugh and smile more than girls. This is unlikely, however, because when a sex difference in smiling is reported, it generally favors girls (e.g., Freedman 1974, 1980). The current research was designed to analyze sex differences in preferences for interaction with peers. It was hypothesized that males prefer interaction with peers more than females. The hypothesis was tested in two ways. In the first study, using a partial replication of the procedure of Charlesworth and Dzur (1987), four- and six-year-old children's enjoyment of peer interactions in a school setting was observed. In the second study, six- and nine-year-old children's preferences for interaction with peers were assessed through interviews regarding their companions in their neighborhoods and the playmates with whom they chose to share their favorite activities.

STUDY 1 Method

Participants. Classes were selected for participation if at least five children of each sex in the class received parental consent to participate. In total, seven classes of four-year-old children from five nursery schools and six kindergarten classes of six-year-old children from two elementary schools participated (78 boys and 74 girls). Children came from middle- to

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upper-middle-class backgrounds and more than 95% were white. Thirteen playgroups of boys and thirteen playgroups of girls were formed, each consisting of six children (except for two of the four-year-old and two of the six-year-old girls' playgroups that contained five children). The mean ages in months were 58.29 (s.d. = 3.00) for the four-year-old females, 57.59 (s.d. = 3.50) for the four-year-old males, 72.03 (s.d. = 1.31) for the six-year-old females, and 73.28 (s.d. = 1.96) for the six-year-old males. Children were selected on the basis of their number of reciprocal friendship ratings using the sociometric technique developed by Asher, Singleton, Tinsley, and Hymel (1979). Complete details of the selection criteria are described in Benenson, Apostoleris, and Parnass (1997). Briefly, in every class for each sex, those children who received parental consent were ranked in order of number of reciprocal same-sex friends in the class. Children of each sex who were ranked highest were selected for inclusion in either the girls' or boys' playgroup that was created in each class. If children of the same sex were tied in rank, the child who had the most reciprocal friendship ratings with those children already selected for participation in a playgroup was chosen. In all playgroups, the three children who were ranked highest in number of reciprocal friendship ratings in the class had at least unidirectional and generally reciprocal friendship ratings with one another. The fourth highest ranked child had at least one reciprocal friendship rating with another child in the playgroup. Finally, the fifth and sixth ranked children varied in whether they had reciprocal friendship ratings with any other children in their playgroups. Procedure. The procedure was based upon the one created by Charlesworth and Dzur (1987). To avoid creating a competitive situation, however, children were given only animal puppets and foam balls with which to play. Further, enough puppets were available so that each child could have at least one puppet. Details of the procedure are reported elsewhere (Benenson et al. 1997). All data collection took place in the spring to ensure that children were familiar with one another (classes generally form in the fall). The setting consisted of placing a 5' x 7' green carpet along with eight non-sex-typed animal puppets and two hand-sized foam balls in a room in the school. Both puppets and foam balls have been reported to be used equally by males and females (Fagot 1985). Children were told that they could play freely and have lots of fun for 15 minutes. In order to create a realistic and comfortable setting, little attempt was made to keep children on the carpet after play had begun. Children were interrupted only if they began to hurt one another. Children's activities included chasing one another, creating and acting out stories, playing catch, devising and playing a variety

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of games, lying on the carpet, and running around. Children enjoyed playing together and appeared oblivious to the recording equipment. All children were given brightly colored t-shirts to wear, so they could be easily identified on videotape. A camcorder was placed on a tripod nine feet in front of the children in full view. Two graduate student experimenters, either two females or one female and one male, were in the room with the children during the play session: One sat several feet to the right of the children to ensure that no child was hurt; the second operated the camcorder. Several days before the study began, a warm-up day was held to allow children who would participate in the actual study to become familiar with the procedure, and children who would not participate to feel included. Videotapes were coded for children's degree of enjoyment. Coders viewed the middle three minutes (minutes five through eight) of each of the 26 same-sex groups and rated children on a one (almost none) to six (a lot) scale indicating the degree of fun the child was having. These three minutes from the middle of the observations were selected so any sex differences in latencies to feel comfortable or become bored in the setting would be eliminated. In order to utilize a procedure that was different from the one employed by Charlesworth and Dzur (1987) in which frequencies of specific instances of positive affect were tabulated, coders were explicitly instructed not to focus on instances of laughing or smiling per se, but rather on a global rating of the child's enjoyment. To determine children's overall enjoyment, coders were asked to imagine that at the end of the three minutes they could ask the child how much she or he wanted to continue playing. They were instructed to make their ratings based on how they believed the child would respond. Children had been ranked in terms of number of friends in their classes before the study began, and girls and boys were matched on rank (see Benenson et al. 1997). Because four of the girls' groups contained only five children, whereas all of the boys' groups contained six children, it was decided to rate only four children in each playgroup. Only the four children who had been ranked highest in terms of number of friends in their classes were rated. The children with the fewest friends were not coded because they were least likely to be friends with the other children in their playgroups and, hence, the context was deemed to be less ecologically valid for them. All children who were rated, therefore, had a reciprocal friendship rating with at least one other child in their playgroup. Coders were blind to the hypothesis of the study. Each coder rated only one child in a playgroup. Reliability was determined by having four additional coders rate individual children in 13 of the 26 playgroups. For each coder, therefore, another coder rated half of the same children. Pearson productmoment correlations ranged from .78 to .91 with a mean of .85. One score

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per playgroup was created by averaging the four children's ratings within each playgroup. This resulted in 26 scores. Results A repeated measures analysis of variance (ANOVA) was conducted with age (four or six years), class nested within age, and sex as the between-subjects variables; children within playgroup as the repeated measures variable; and level of enjoyment as the dependent variable. The analysis yielded a significant effect of sex, F(1,11) = 4.75, p = .05, and a significant effect of age, F(1,11) = 15.83, p < .005, but no significant effect of class, F(11,11) -- 1.42, or interaction effect, F < 1. Table 1displays the means. Consistent with the hypothesis, males were significantly more likely than females to be rated as enjoying peer interactions. Although the interaction effect was not significant, examination of the means shows that the sex difference was much more pronounced for the six-year-old than the four-year-old children. In fact, in all six kindergarten children's groups, males were rated as enjoying their interactions more than females, whereas this was true for only four of the seven four-year-old classes. Results from this study provide support for the hypothesis that males enjoy peer interaction more than females, though the sex difference was more apparent for the six- than the four-year-old children. Although this result is consistent with the findings reported by Charlesworth and Dzur (1987), both studies are limited in that they analyze interactions of children only in one setting. It is possible that the controlled nature of the setting was more aversive to girls than to boys. Consequently, with the aim of examining more naturalistic interactions, it was decided to interview children about their interactions in their homes and neighborhoods and about their favorite activities and the individuals with whom they share these activities.

Mean (and s.d.) Ratings of Degree of Enjoyment of Peer Interaction for Females and Males at Both Age Levels

Table 1.

Age Sex

Four years

Six years

Females 3.82 (.47) 4.38 (.34) Males 4.05 (.72) 4.94 (.38) Note: Degree of enjoyment ranged from 1 (almost none) to 6 (a lot).

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STUDY 2 Method Participants. Because the previous study suggested a stronger sex difference in children's enjoyment of peer interactions at six years of age, sixyear-old children were recruited for participation in this study. In addition, a second sample of children nine years of age was added to examine whether similar results would be found later in childhood. Children from the first and fourth grades of two elementary schools were recruited for participation. None of the children in the first study participated in the second one. The first 15 females and males at each grade level who received parental consent to participate were included in the study. Because of an error, 16 girls from the first grade were included. More than 95% of the children were white and of middle- to upper-middle-class backgrounds. The mean ages of the children were 82.13 months (s.d. = 3.12) or 6.84 years for the six-year-old females, 80.27 months (s.d. = 3.10) or 6.69 years for the six-year-old males, 117.27 months (s.d. = 4.88) or 9.77 years for the six-year-old females, and 116.73 months (s.d. = 3.10) or 9.73 years for the six-year-old males. Procedure. Children were individually interviewed in an empty room at the child's school by a female graduate or undergraduate student. Interviewers were blind to the hypothesis of the study. Because children in schools have limited access to adults and older and younger children, children were not interviewed about their social interactions at school. Further, unlike many studies of social support (e.g., Belle 1989; Bryant 1985), the emphasis was not on children's social networks, but rather on those individuals with whom children prefer to interact. After a brief warm-up in which children were told that the researcher was interested in learning about the people in children's lives and were assured that their responses would be completely confidential, a series of questions was asked in a standardized order. Responses were audiotaped, because pilot testing had demonstrated that writing down responses was distracting the children. The interview began with several questions regarding children's backgrounds and family compositions. All children lived with at least one biological parent and had at least one sibling. The interview then was divided into two parts. In the first part, children were asked to name those individuals in their homes and neighborhoods with w h o m they spend time. For the second part, children were asked to list their three favorite activities, then to name those individuals with whom they most enjoy sharing these activities.

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More specifically, for part one of the interview, children were first asked to name those adults around their houses and in their neighborhoods with w h o m they spend time. ("Are there any adults around your house and in your neighborhood you spend time with? Who?") Next, they were asked to name those children around their houses and in their neighborhoods with whom they spend time. ("Are there any particular children around your house and in your neighborhood you spend time with? Who?") The probe "Anyone else?" was given after each child's response until the child responded negatively. For each individual named, children were asked to identify the individual's sex and age. For part two of the interview, in order to examine enjoyment as concretely as possible, children were first asked to describe their three favorite activities. Activities listed by children were diverse and included viewing movies, talking, painting, dancing, basketball, soccer, swimming, and horseback riding. For each activity, children were then asked to list the people with whom they engaged in that activity. ("Who do you like to do [favorite activity[ with?") As before, the probe "Anyone else?" was given after each child's response until the child responded negatively. Children were again asked to identify the sex and age of each person named. To create a measure of preference for interaction with peers versus with other children and adults, for the first part of the interview in which children were asked with whom they spend time in their homes and neighborhoods, each individual named by the child was categorized as either a peer, other child, or adult. All individuals who were within two years of the child's age were categorized as peers. Individuals more than two years older or younger than the child were categorized as "other children." Individuals over 18 years were categorized as adults. Mothers, fathers, and babysitters were excluded, because it was assumed that all children spend some time with parents and babysitters, regardless of whether they choose to do so. Because the goal of study two was to measure children's preferences for interaction, excluding individuals with w h o m children are forced to interact created a more pure measure of children's choices. Further, because girls are found to spend more time with family members and to stay closer to home than boys (for reviews, see Belle 1989; Whiting and Edwards 1988), exclusion of members of the immediate household should constitute a more stringent test of the hypothesis. That is, if girls were found to include a greater proportion of adults and older and younger children as opposed to peers than did boys even when parents and babysitters were excluded, then strong support would be provided for a sex difference in preference for peer interaction. Individuals with whom the child had no interaction but who were simply present in the child's house or neighborhood, such as parents'

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friends or parents of friends, were also excluded unless the child indicated a relationship with the individual. For each child, preference for peer interaction was analyzed by dividing the total number of peers named by the child by the total number of individuals (peers, other children, plus adults) the child named, resulting in a proportion. For the second part of the interview, in which children were asked to name those individuals with whom they shared their favorite activities, individuals were similarly categorized as either peers, other children, or adults. For this part of the interview, all individuals including parents and babysitters were included in the analyses. All individuals who were named were assumed to be associated with the enjoyment children derived from the activity. Further, because for both boys and girls virtually all of these activities occurred away from homes, concern about girls having less freedom than boys to leave parents and babysitters behind was reduced. In addition, because the emphasis was on pleasure, other confounding factors such as girls' greater reliance upon parental figures in times of stress were also reduced. Several children did not name any other individual with w h o m they participated in one of their favorite activities, indicating that they enjoyed performing the activity alone. If a child named the same individual in more than one activity, the individual was counted more than once. The aim was to focus on children's desire to share their favorite activities with peers rather than with other children or adults, and not with the number of different individuals in a child's network. Thus, if a child had one best friend who was a peer with w h o m she participated in all three activities, that best friend would be counted three times in the peer category. As in part one of the interview, for each child, preference for peer interaction was analyzed by dividing the total number of peers named by the total number of individuals (peers, other children, plus adults) listed, resulting in a proportion. Results

For the first analysis, the total number of individuals with w h o m children reported they spent time at home or in their neighborhoods was analyzed. An ANOVA with sex and grade as the independent variables yielded no significant effects of sex, grade, or sex x grade interaction, F < 1, (mean = 2.81, s.d. = 1.80 for grade one females; mean = 2.67, s.d. = 1.50 for grade one males; mean = 2.67, s.d. = 2.61 for grade four females; mean = 3.60, s.d. = 2.41 for grade four males). Consistent with the same analysis which was performed across 12 cultures (Whiting and Edwards 1988), girls and boys were not found to differ in the number of individuals with whom they spent time.

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The second analysis consisted of examining the p r o p o r t i o n of individuals w h o were peers, and even more specifically, the p r o p o r t i o n of individuals w h o were same-sex peers. An ANOVA was p e r f o r m e d on each of these measures with sex and grade as the i n d e p e n d e n t variables. For the p r o p o r t i o n of individuals w h o were peers, there was a marginally significant effect of sex, F(1,57) = 3.19, p < .08, and no effect of grade, F(1,57) = 1.20, n.s., or the interaction term sex x grade F(1,57) < 1. Table 2shows that there was a trend for males to spend time more with peers compared with females. For the p r o p o r t i o n of individuals w h o were same-sex peers, there was a significant effect of sex, F(1,57) = 7.29, p < .01, indicating that males spent time with a higher proportion of individuals w h o were samesex peers than did females. The effect of grade, F(1,57) = 2.67, p < .11, and the interaction effect, F(1,57) = 2.77, p < .11, did not quite attain significance, t h o u g h as s h o w n in the table, the means differed more between the sexes for nine-year-old than six-year-old children. The same analyses were repeated for the individuals with w h o m children preferred to share their favorite activities. For the first analysis, the total n u m b e r of individuals with w h o m children reported they shared their favorite activities was analyzed. Again, an ANOVA with sex and grade as the i n d e p e n d e n t variables yielded n o significant effects of sex, F(1,57) = 1.37, n.s.; grade, F(1,57) = 1.74, n.s.; or sex • grade, F(1,57) < 1, (mean = 5.56, s.d. = 2.48 for grade one females; m e a n = 7.67, s.d. = 5.58 for grade one males; m e a n = 8.00, s.d. = 5.82 for grade four females; m e a n = 10.47, s.d. = 13.16 for grade four males). Girls and boys did not differ in the n u m b e r s of individuals they n a m e d in their favorite activities. The second analysis consisted of examining the p r o p o r t i o n of individuals w h o were peers, and even m o r e specifically, the p r o p o r t i o n of individuals w h o were same-sex peers. An ANOVA was p e r f o r m e d on each of

Table 2. Mean (and s.d.) Proportions of Individuals Who Were

Peers in Homes and Neighborhoods for Females and Males at Both Age Levels Age Sex

Total Peers Females Males Same-Sex Peers Females Males

Six years

Nine years

0.30 0.39

(.28) (.25)

0.34 0.50

(.32) (.28)

0.19 0.26

(.26) (.22)

0.19 0.48

(.28) (.27)

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these measures with sex and grade as the independent variables. For the proportion of individuals who were peers, there was a significant effect of sex, F(1,57) = 5.86, p < .02, and a significant effect of grade, F(1,57) = 6.11, p ~ .02, but no significant interaction effect, F < 1. Table 3 shows that males named a significantly higher proportion of peers in their favorite activities than did females. In addition, nine-year-old children named a significantly higher proportion of peers than six-year-old children. For the proportion of individuals in the child's activities who were same-sex peers, there was a marginally significant effect of sex, F(1,57) = 3.07, p < .09; a significant effect of grade, F(1,57) = 4.60, p < .04; but no significant interaction effect, F ~ 1. As shown at the bottom of Table 3, there was a trend for males to name a higher proportion of same-sex peers in their favorite activities than females. Further, nine-year-old children named a significantly higher proportion of same-sex peers than six-year-old children.

GENERAL DISCUSSION Results from the two studies provide strong support for the hypothesis that boys prefer interactions with peers more than do girls. In the first study, based on observations of children playing in same-sex groups of peers, boys were rated as enjoying themselves more than girls, thereby replicating and extending the results of Charlesworth and Dzur (1987). Because both Study I and the Charlesworth and Dzur study occurred at schools in controlled settings, the results may have been influenced by the context. Therefore, in Study 2 children were interviewed about the individuals with whom they spent time in their homes and neighborhoods

Table 3. Mean (and s.d.) Proportions of Individuals Who Were

Peers in Favorite Activities for Females and Males at Both Age Levels Age Sex

Total Peers Females Males Same-Sex Peers Females Males

Six years

Nine years

0.36 0.55

(.46) (.43)

0.55 0.83

(.35) (.24)

0.30 0.44

(.43) (.38)

0.48 0.67

(.35) (.30)

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and about the individuals with whom they participated in their favorite activities. No sex differences were found in the total number of individuals named by children in their homes and neighborhoods or in their favorite activities. The proportion of individuals named that were samesex peers, however, was significantly higher for males than females. For the strongest test of the hypothesis, in which children first stated their favorite activities, then named those individuals with w h o m they participated in these activities, boys named a significantly higher proportion of peers in these activities than did girls at both age levels. The results are consistent with an evolutionary explanation in which peers are viewed as providing fewer benefits to females than to males. Females of reproductive age who maintained bonds with other female peers who also had offspring would receive fewer resources for themselves and their offspring as opposed to females who forged bonds with close biological relatives. In contrast, those females who maintained bonds with biological relatives who would be willing to sacrifice their own interests to give to the females' offspring would accrue more benefits. Females would have evolved then to favor affiliation with close biological relatives over peers. Likewise, males of reproductive age who maintained bonds with biological relatives as opposed to peers would be more vulnerable when fighting and less skillful in hunting. Older and younger biological relatives would not have the same degree of physical strength as other relatively young peers would have. In contrast, those males who developed bonds with unrelated peers who were at their height of physical prowess would be more successful. Although it would be useful to males to form a tie to a mentor who could provide expertise, only one or two mentors would be necessary and not all males in a group would require such ties. Having ties to many elderly, experienced mentors would be much less adaptive than forming bonds with many peers who excelled in physical strength and coordination. The conclusion that boys prefer interaction with peers more than do girls is consistent with data comparing the amount of time males and females spend with peers obtained from studies on the majority of species of non-human primates and across several non-western cultures. This is the first study, however, to examine sex differences in investment in peer relationships directly. This study challenges Sullivan's (1953) influential theory of the importance of positive peer relations in middle childhood for healthy adult development, a theory that was created based on interviews with males. Results from the current research suggest the theory may not be equally applicable to females. Relationships with younger and older children, teachers, and other adults may be more important for girls' social development. As children

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develop in western societies, they spend less time with teachers and other adults or with older and younger children and more time with peers, which may be especially stressful for females. This is consistent with a recent study demonstrating that those girls who were most successful in junior high school were the ones who had an adult mentor on w h o m they could depend (American Association of University Women 1996). For the many girls without an adult mentor in adolescence, however, peers may be the only ones available to provide emotional support. Previous studies have shown that girls spend more time with adults than do boys in both preschool and middle childhood (e.g., Belle 1989; Feiring and Lewis 1989; Huston and Carpenter 1985; Huston et al. 1986; Whiting and Edwards 1988). Sex differences found in prior research, however, may have been due to girls' greater willingness to turn to adults for help in times of stress (for a review, see Belle 1989), or to parents" universal tendency to keep girls closer to home than boys (e.g., Whiting and Edwards 1988). This is the first study to provide evidence that it is girls' preference, rather than need for social support or lack of alternative social partners, that leads them to interact with a lower proportion of peers than boys. More specifically, in both studies, the sex differences obtained were not confounded with sex differences in factors related to social support. Children's enjoyment and choices of partners were examined in pleasurable and non-stressful contexts. Further, it is highly unlikely that girls' lesser enjoyment of peer interaction and preferences for interaction with lower proportions of peers compared with boys were due to greater parental restrictions on girls than boys. In western societies, girls and boys attend preschools and elementary schools in equal numbers. Thus, girls do not have less experience with peers than boys. Second, when parents do restrict girls' interactions more than boys', they most likely restrict girls' interactions with older children and adults, not peers, and especially not same-sex peers. Consequently, if parental restrictiveness were the only factor operating, this would result in girls having a higher, not lower, proportion of peers, especially same-sex peers, than boys in their interactions in their homes and neighborhoods and in their favorite activities. In fact, the opposite result was obtained. Finally, even when parents and babysitters, who in western cultures provide the most social support to children, and universally are found closest to home, were excluded from the analyses, girls were found to spend time with a lower proportion of peers than boys were. Results from these two studies provide strong support for the hypothesis that girls enjoy peer relationships less than boys: Each study posed a slightly different question and utilized different methods, yet the results converged. In the first study, boys' and girls' enjoyment of peer interaction

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was observed. In contrast, in the second study children's self-reports of their companions in their homes and neighborhoods and of their preferred playmates in their favorite activities were collected. These two studies provide separate sources of evidence supporting the hypothesis that girls enjoy peer interaction less than boys. Because most studies of peer relations in western societies occur in schools where interaction is confined to others of the same age, the second study provided a relatively rare look at children's activities in contexts in which they had a greater choice of partners. Interestingly, across the social sciences and in ethological studies of human beings, females' relationships have always been considered to be more egalitarian than males' (e.g., Gilligan and Wiggins 1988; Omark et al. 1980; Tannen 1990). This may be due to researchers' focus on peer relationships in which males have been found consistently to engage more frequently than females in interactions involving dominance and status. Consistent with this explanation, after a review of studies of sex differences in children's and adults' competition with peers, Knight and Kagan (1989) concluded that males were more likely than females to attempt to gain superiority over their peers in the number of resources they acquired. Females, however, were more "individualistic" than males--that is, they were interested only in acquiring resources for themselves and were significantly less interested than males in their peers' fates. Females' most important relationships may be with young children and with mothers and grandmothers, with whom there is no need to negotiate status because it is already determined. It is reasonable to negotiate status only with peers with whom status relationships can fluctuate. Females, traditionally considered egalitarian in their relationships, in fact may be more invested than males in hierarchical relationships. If this were true, it would mean that peer relationships, including marital relationships and business relationships, would be approached from largely differing perspectives for males versus females. Established hierarchies permit relationships to function more smoothly: Males continually negotiate their hierarchies with peers, whereas for females the hierarchies are predetermined. When males must engage in predetermined hierarchical relationships with younger and older individuals or when females must negotiate the hierarchies with peers, each sex may be encountering contexts in which they have less experience and more difficulty. Limitations of the current study include the fact that findings are based upon white children from middle- to upper-middle-class backgrounds. Whether the results would generalize to other populations of children remains to be determined. The hypothesis for this research, however, was derived from anthropological studies of children from a variety of back-

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grounds, strongly suggesting generalizability across cultures. Another shortcoming is that in the first study children were observed in a semistructured setting. If girls were uncomfortable with the degree of structure, the setting may have inhibited their enjoyment. It is boys, however, who have been shown to enjoy structured settings less than girls (e.g., Huston et al. 1986), so it is likely that the findings from Study 1 underestimated the magnitude of the sex difference in enjoyment of peer interaction. Systematic observations of children in less controlled settings, however, such as on playgrounds, would further enhance the validity of the current findings. In Study 2, excluding parents and babysitters from analyses of the first measure probably led to underestimation of the magnitude of the sex difference in proportion of peers versus other children and adults in homes and neighborhoods, because girls have consistently been shown to spend more time with adults at home than boys (e.g., Whiting and Edwards 1988). Similarly, in non-western cultures where parents restrict girls' movements more than is common in western societies, sex differences in enjoyment of peer interaction would most likely have been even more pronounced. In addition, the current theory and data apply to females who have not yet passed their reproductive years and to males whose physical strength has not yet begun to wane. When females can no longer reproduce and males are less physically adept, then the theory is no longer applicable. With age, peer relationships may become more important for females and family relationships may assume greater significance for males. Finally, enjoyment of and preferences for peer interaction represent only two potential measures of investment in peers. Similar results using other measures of investment, such as willingness to sacrifice other relationships for peers or responses to separation from peers, would further validate the current findings. Several of the most seminal observational studies of peer relations in middle childhood have included only boys (e.g., Coie and Kupersmidt 1983; Dodge 1983; Sherif and Sherif 1964). Researchers may have believed intuitively that girls' peer relations are less important at this age. Results from the current study provide strong support for a sex difference in investment in peer relationships in childhood. From a clinical perspective, current research on peer relations in childhood may be neglecting the most important relationships in girls' lives. Future research is needed to examine the developmental functions of peer relations separately for females and males at different ages.

Support for this project was provided to the first author by a Faculty of Graduate Studies Research Award from McGill University. The authors would like to thank Dr. David Quattropani and Dr. Robert Villianova, superintendents of the Canton

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and Farmington Public School systems, respectively; Mrs. Helen McMullen, Mrs. Cheryl Kolczko, and the late Geraldine Smith, principals in those school districts; Rabbi Zev Lanton, principal of the Hebrew Foundation School; Mr. Soly Benamton, Principal of the United Talmud Torah School; Dr. Cathy Bode, Mrs. Janet Cosgrove, Mrs. Susan Finkle, Mrs. Debby Grandon, Mrs. Helen Peterson, Mrs. Barbara Swanson, and Mrs. Carol Van Hoff, directors of the nursery schools; and all of the teachers in these schools for their support of the project. In addition, thanks to Marie-Claire Albanese, Nicholas Apostoleris, Athena Christakos, Amanda Lanciard, Beth Landau, Frank Lilly, Illana Lukshinki, Julie Parsons, Maria Tricerri, and Stephanie Wiener for their help in collecting and analyzing the data. Finally, many thanks to all of the children who participated in the project.

Joyce F. Benenson, Ph.D., is Assistant Professor of Applied Developmental Psychology in the Department of Educational and Counselling Psychology at McGill University. Her research focuses on sex differences in patterns of social organization and the influence of social organization on competition and cooperation. Tamara Morganstein, M.A., is a doctoral student in the School Psychology Program in the Department of Educational and Counselling Psychologyat McGill University. Her research interests lie in understanding social competence m children. Rosanne Roy, M.Ed., is a doctoral student in the Applied Developmental Program in the Department of Educational and Counselling Psychologyat McGill University. Her research examines sex differences in competitive strategies from an evolutionary perspective.

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