It’s no secret that humans are visually oriented animals, and while we are capable of using other senses such as smell and sound, we might not use them as much to recognize others. Behavioral ecologist Michael Sheehan of the University of California, Berkeley discusses the types of senses different species use for recognition.

"In the case of birds a lot of recognition is based on acoustic signals so they have different vocalizations and they can use that to recognize each other. A lot of animals of course use smell. Dogs are going around peeing everywhere, smelling everything. It’s just not what primates do. We’re much more visually oriented. We may not necessarily be able to tell the pee of one dog from another but a dog certainly can. So they can use that information to do that."

Sheehan says that there is selection in animals to be more distinctive for mating opportunities and other social interactions.

"But the basic idea that there might be selection for individuals to be more distinctive is something that people have shown evidence for in all different types of senses in different species."