The interest in the whites of the eyes issue has caught my notice. The news that humans are the only primates with whites to their eyes seems like great evidence that evolution has been promoting joint attention along the line of human descent. I wondered if the fact of being out on open savanna might have had anything to do with it, so I looked up the eyes of some African plains animals. It appears that being out in the open does not promote white eyeballs, so the attention hypothesis still holds.
In fact, we can think of a very good reason why whites of the eyes (if indeed they do facilitate joint attention) would be a disadvantage on the savannah in a predator-prey situation: the prey doesn't want a predator to be able to tell where it is going to run.
Posted by: TLTB | November 15, 2006 at 10:13 AM