It was a common question when face recognition first debuted in iPhoto: does the Faces feature recognize pets? The answer is no. And armed with the background into how facial recognition works, you can understand why: a cat’s color is not usually going to be a skin tone, nor will your poodle’s facial geometry match that of a human face—even if your friends claim you two look alike.
iPhoto may occasionally recognize an animal’s face, but consider those incidents happy accidents. And keep in mind that if you want to create a corkboard tile for your critters, you can always manually add their faces, as described on page 26.