Dogs' sense of smell is so acute that responses we assume are triggered by sight may actually be based on odors caused by people's diet, grooming products, or metabolic or hormonal differences. In other words, did Percy "see" that the distant fishermen reminded him of people he doesn't like, or was he triggered by scent? Put another way, does your dog hate the pizza delivery man because he's Hispanic, or does the dog have a fear response to the scent of garlic, which might explain why he also has a thing for your cousin, whom even you can tell eats a lot of garlic. Given the possibility that the mysteries of a dog's sensory realm could be used to reinforce negative stereotypes, this subject makes people—and even animal behavioralists—uncomfortable. But is a dog linking a scent to fear and hate somehow more ridiculous or offensive than people doing the same thing using skin color, wardrobe, or educational background?