 A series of studies in 1999 provided observers with silent clips that were either ten-seconds or one-second long in which heterosexual and homosexual subjects discussed their academic and extracurricular activities.Observers were well-above chance in correctly identifying which participants were heterosexual or homosexual and remained correct far above chance even when the videos were digitally degraded so that only the outlines of the individuals were presented.Another study examined perceptions of gait and their relationship to sexuality assessment.