A characteristic of extinctionExtinction The weakening of behavior through non-reinforcement or “ignoring” the behavior. In extinction, nothing is added or removed from the environment. For example, a treat lies on the other side of a fence. A dog reaches his paw under, but cannot reach the treat. Because reaching for the treat doesn’t work—because it isn’t reinforced through success—the dog will eventually quit reaching for the treat. in which a behavior that was thought to be extinct unexpectedly reappears. If the trainer ensures that the behavior is not reinforced, it will disappear again quickly.