Y: Hey Don, take a look at these photos and tell me what you see.

D: Well Yaël, I see a cat, a dog, and a person. Does that mean something special?

Y: Not for a human. But did you know that French scientists tested dogs to see if they could recognize the faces of other dogs on a computer screen?

D: That seems pretty easy to me.

Y: Think about it, Don. There are sheep dogs that look like mops, skinny greyhounds, and bulldogs with shortened faces. There are even Chinese crested hairless dogs. There are more than four hundred pure breeds of dogs registered.

D: I suppose it would be difficult to recognize some dogs as dogs, especially if there are no other clues like scent.

Y: To see if nine pet dogs could recognize their own species, the researchers used a computer screen to test them. First they trained them with a clicker and rewards to teach them how to select a dog from two pictures shown on the screen. They were given pairs of pictures of faces from various dog breeds and cross-breeds, and faces of other animal species, including human faces.

D: They weren't just learning a trick?

Y: No, once the training was over, and the dogs knew they were supposed to select the dog, the real testing began. They were shown one hundred fourteen pairs of images, including dog faces, images of forty non-dog species, including domestic and wild animals, and humans.

D: And dogs could recognize their own species?

Y: The results suggested that dogs can identify very different dogs, despite the diversity in breeds. It seems they are almost as smart as you, Don.