Figure 1. Histogram of the frequency distributions of scores for all female- (n = 148) and male-directed (n = 151) wing-spread song displays recorded from the 7 male brown-headed cowbirds that featured in the playback video stimuli presented to the female subjects.
Recordings used as stimuli were selected from these recordings as described in the text. Note the overlap in the distribution of scores for male- and female-directed displays.