I never knew how complex life as a dog was until I started working in a San Francisco dog kennel. For example when a dog wants his subordinates to know he is the leader, he will make it pretty obvious. The types of expressions a challenged dog uses to let the rest know he is in charge are by looking into the other dog’s eyes firmly and penetratingly while at the same time showing all his teeth, he will also hang his tongue out of his mouth and his body will be rigid in a dominating exhibition of hostility. The dog will also lean forward, as if preparing to attack his adversary to show how formidable he is. The dog will also usually emit a deep growl. When dogs have conflicts, they look into each other’s eyes and show their teeth and growl. An aggressive dog will lift his lips as much as possible and this causes his front teeth to show a lot while at the same time moving forward. Through this type of deliberate demonstration of power and by doing these expressions, the aggressive dog is giving his opponent an opportunity to back off. The underdog will then have to slowly back off to not alarm the aggressive one or stimulate him to attack. A threatening growl from a dog can be frightening resource that is used to put a doubt in the mind of his opponent to show his capacity to come out victoriously. A dog that does not want to lose his “trophy” will not be shy about showing he is not fooling around by growling ferociously that will be surprisingly fear provoking for an animal of his same size or smaller. This type of reaction is difficult for anyone to ignore, and it is an evident sign that getting close to him would be a dangerous thing to do.