To explore the hypothesis that girls and women smile more frequently than boys and men, 16,514 photographs of students (kindergarten to college) from school yearbooks were studied, as were photos of faculty and staff members. The predicted gender difference in smiling was small and nonsignificant until Grade 4, when a statistically significant difference was first obtained. The gender difference reached its peak in grade 9 (effect size = .275) and remained relatively constant through adulthood. Systematic study of yearbook photos from one high school during the period 1968-1993 revealed no change in the gender difference over time. Discussion focused on the emergence of the smiling difference during preadolescence and the theoretical implications of such a finding.
Over the past 20 years, abundant empirical evidence has mounted showing that women smile more frequently than men across a variety of situations (Bugental, Love, & Gianetto, 1971; Chaiken, 1979; Frances, 1979; Halberstadt & Saitta, 1987; Henley, 1977; LaFrance & Carmen, 1980; Mackey, 1976; for reviews, see Hall, 1984, and Hall & Halberstadt, 1986). A number of theoretical explanations exist for this gender difference in smiling, including sex role conformity (LaFrance & Carmen, 1980; Mackey, 1976), status and power (Deutsch, 1990), submissiveness or subordination (Goffman, 1987; LaFrance, 1985), learned expressivity (see Hall, 1984), and generation of leniency (LaFrance & Hecht, 1995). Despite the abundance of research and theory linked to smiling, surprisingly little is known about the developmental age when this gender difference first occurs. A major goal of the present paper was to identify, through a largescale, systematic analysis of school yearbook photos, the age at which gender differences in smilin g emerge.
Based on a meta-analysis of 18 studies of infants, 20 of children, and 23 of adults, Hall (1984) concluded that there was no gender difference in social smiling among infants and children but a moderately strong difference among adults, with women smiling more than men. Clearly, the gender difference must develop sometime during adolescence or, perhaps, late childhood. Unfortunately, there is a dearth of research on adolescents, especially early adolescence, even though this may be a period of heightened awareness and exploration of gender roles (Hill & Lynch, 1983). Notably, two studies (Berman & Smith, 1984; Kolaric & Galambos, 1995) that used experimentally composed dyads of adolescents both reported significantly greater smiling among girls than boys. Still, additional research covering late childhood and early adolescence is clearly needed.
The study of gender differences in smiling can contribute to theory and research on the development of gender roles. According to both social learning theory (see Lott & Maluso, 1993) and gender schemata theory (Bem, 1985), the socialization of gender occurs during childhood, but gender schemas do change and evolve after childhood (Jacklin & Reynolds, 1993). Block (1976) reported that sex differences increase with age, appearing far more often after age 12 than prior to age 5. Learning the age at which gender differences in smiling emerge, relative to adolescence, can contribute both to a greater understanding of gender role development and, more specifically, to reasons for this gender difference. For example, Hall and Halberstadt (1986) found social tension to be the best situational predictor of smiling among adults. If a specific age at which girls begin smiling more than boys can be determined, then research into the causes and meanings of smiling can focus more narrowly on such a particular age group.
Because of the heightened level of self-consciousness among adolescents (Salkind, 1990), the study of smiling among adolescents, particularly in real-life social situations, may be especially difficult. One way in which …