approachingsignificance:

Evolution Is Written All Over Your Face

Why are the faces of primates so dramatically different from one another? A very interesting study that examines the differences in faces amongst New World primates.

Humans have pretty bare faces, which may allow us to see facial expressions more easily than if, for example, we had many colors in our faces.

This finding suggests that facial expressions are increasingly important in large groups.  If you’re highly social, then facial expressions matter more than having a highly complex pattern on your face.