People are really for the birds! At least, in one sense. We understand much of avian behavior because birds, like ourselves, depend heavily on vision. The brilliant color of a bird is almost instinctively understood as being sexual in nature, since humans employ similar displays to entice potential mates.
What we don't understand so easily is behavior based on smell. How does one mouse determine the sex of another, apparently identical in looks, without being overly personal? How do male moths zero in on a receptive female in a distant arroyo? We've slowly eked out some understanding, but in the process have pretty much decided that insects, at least, are entirely scent oriented. A decision, however, recently overturned.
Members of a colonial species of wasp show highly variable facial color
patterns. Scientists altered the patterns of some with paint, but on others, merely
duplicated their own patterns. Released back into the colony, the altered wasps were
often harassed, while those who preserved their original pattern were accepted.
Clearly, face recognition‐not smell—at work among these wasps. 
Contributor: Arthur H. Harris, Laboratory for Environmental Biology, Centennial Museum, University of Texas at El Paso.
Desert Diary is a joint production of the Centennial Museum and KTEP National Public Radio at the University of Texas at El Paso.