Why Should Dogs Respond in an Emergency?

Dogs sense a great deal about our inner lives by observing our behavior and also by sniffing out our excretions. Even if they're really sensitive to our physiological or behavioral changes, that doesn't mean they always know the meaning of those changes. The dog may in fact be a comfort, but what the dog definitely knows is, you know, I'm doing something different. Like, let's go see what's going on here.