Running head: DEVELOPMENT OF GENDER CATEGORIES The development of gender categories in infancy and childhood

The development of gender categorization and the effect of gender-typicality (i.e., masculinity/femininity) on categorization of dynamic faces were investigated from infancy through childhood. Studies 1 and 2 tested 5-, 6-, 8-, and 11-month-old infants in a habituation task with either typical or atypical faces without cultural cues (e.g., hair or clothing). The results demonstrated that by 6 months, infants categorize the typical faces. However, even 11-montholds were unable to categorize the atypical faces. Given the limited ability of infants to categorize atypical faces, Study 3 focused on the abilities of preschoolers. The results indicated that while 3and 4-year-old children were able to categorize all faces above chance, they were more accurate with typical faces than atypical faces and more accurate with faces which included hair cues than those faces which had the hair occluded. This is the first set of studies to investigate the development of a single skill from infancy through childhood and indicated that while the ability to categorize facial gender begins as early as 6 months of age, it takes until late childhood to reach a level of expertise that is comparable to adults.