Little is known as to how physiological differences may affect behaviors associated with visual information gathering. Males and females brown-headed cowbirds (Molothrus ater) are exposed to different selection pressures. I tested the hypotheses that these different selection pressures require males to have a higher density of photoreceptors to detect the female's courting display, and that females require to expose their organs used to collect visual information to the object of interest with a more frequent succession to obtain quality visual information. Females had a significantly lower density of single and double cones than males. Females had significantly higher head-movement rates than males when visually exploring stationary objects. These results suggest that females have lower visual resolution than males, and compensate for that by moving their heads more quickly and exposing objects to different parts of the retina.