Dogs are territorial animals that will dominate other dogs and people with its physical prowess. As the dog’s relationship with humanity evolved, certain aspects of a dog’s personality became valued. Since dogs are grateful for the food and shelter that is provided by its human family, a dog repays this gratitude by protecting its family, home and property.
A dog is naturally aggressive for survival reasons and it will use aggression to protect its family, food and shelter when it lives in the wild. As a territorial and domestic animal, a dog feels that it must protect its home and property from other dog’s and people. A territorial dog is valued for its protective feelings and because such a dog will defend what it considers as its own with life and limb. A territorial dog will protect people, children and other animals from attack.
A dog will get aggressive to defend its position on the social hierarchy. You can see dogs get aggressive with each other over food and the right to mate. The most dominant dog has to be the most aggressive dog in order to maintain its top dog position.
Aggression can be provoked when a dog is fearful of the unknown. Even a dog that is not a dominant personality can be driven to aggression if the dog is frightened. A dog may become aggressive to unknown animals or people. A person wearing a uniform can trigger some dog aggression.
Aggression may be triggered by a medical condition such as pain or illness. A dog that is friendly and approachable may become aggressive if the dog is not feeling well.
An aggressive dog is potentially dangerous. You must not approach an aggressive dog because you could be hurt. If you meet a dangerous dog, even if the dog is known to you, be careful and do not assume that because you know the dog, that it will not bite you because aggressive dogs can bite.