Figure 5.

Marmosets look directly at faces more often than macaques. (A)- An example image demonstrates how the proportion of time spent looking directly at faces was calculated, with the eye trace from a marmoset (left) and a macaque (right) subject. Faces in each image were marked by ellipses, and the proportion of time the eye was directed into the face region (red points) was divided by the proportion of time the eye was directed out of the face region (blue points). (B) - The distribution of the proportion of time looking directly at faces for marmosets (white bars) is shown compared to macaques (black bars). All subjects were pooled for clarity.