Ever seen a dog flick their tongue and vibrate their jaw after sniffing something interesting? This is called the Flehmen response. It's a special technique dogs use to enhance their sense of Understanding Your Dog's Quivering Mouth: The Joy of Eating Steak Panting To Pup sicles: Why Do Dogs Stick Their Tongue Out? The Cat and Dog House Why is my dog sticking out his tongue? Why is my dog's tongue hanging out? Tuff Pets