Meaning in Motion and Morphology

We employed a novel technique to explore how the body’s motion and morphology affect judgments of sex and gender. Stimuli depicted animated human walkers that varied in motion (gait patterns varying shoulder swagger and hip sway) and in morphology (waist-to-hip ratio). The potency of morphology in categorical sex judgments was confirmed. Visual scanning of the walkers was concentrated in the waist and hip region of the body (Study 1a). This targeted scanning was attenuated, however, when the sex of the target had been prespecified (Study 1b). Body motion permitted categorical judgments of sex, but these judgments were mediated by perceived gender (Study 2). These studies provide converging evidence for the primacy of the body’s shape in categorical judgments of sex. Between 1990 and 1994, ‘‘Saturday Night Live’’ featured 18 sketches of a sexually ambiguous character named Pat, played by Julia Sweeney. Not quite masculine, not quite feminine, Pat was funny because of his/her androgyny. In Pat’s case, every cue that tends to be sexually dimorphic (e.g., hairstyle, clothing, body shape, voice) was uninformative, leaving the character’s sex a mystery. In real life, people may experience fleeting moments in which they are uncertain of someone’s sex, but such occasions are rare. Sex recognition is facilitated by numerous cues, and many of these cues have their foundations in the dynamic structure of the body. The present experiments explored the relative importance of two bodily cues—motion and morphology—for this fundamental social judgment. Perceiving the sex of other individuals has been described as a compulsory judgment (e.g., Stangor, Lynch, Duan, & Glass, 1992), yet pinpointing the mechanisms that underlie this judgment has remained difficult. Studies investigating the perception of the body’s shape and those investigating the perception of the body’s motion offer some insights into these mechanisms, but these two lines of research show little overlap. Investigations of the perception of human motion (e.g., Cutting, Proffitt, & Kozlowski, 1978) typically employ dynamic pointlight displays that lack potentially informative morphological information. Investigations of aesthetic judgments of body shape (e.g., Singh, 1993), in contrast, typically employ static line drawings that lack potentially relevant motion information. The restricted cues utilized by each research tradition have yielded circumscribed knowledge—insights that are precise but that lack breadth. Our approach, in contrast, integrates these disparate lines of work by using animations that vary in both morphology and motion. This novel approach permits a more complete characterization of the strength with which these cues guide social perception.