Women smiled more often and openly than men when photographed for a pleasant, public occasion in 20(th) century United States society

We tested the prevailing view that there is a gender difference for use of a smiling facial expression. Photographs of adult females and males taken i n the United States throughout the twentieth century were analyzed. A compa rison was made between females and males for smiling in individual pair, an d group photographs that were taken for various occasions, all of which cou ld nominally be considered at least neutral and at most celebratory. In nea rly every type of photographic category, women were more likely to smile - and to do so more fully - than men in a comparable setting and time, even t hough the proportion of each gender smiling in photos increased as the cent ury has progressed.