Dog aggression expresses itself in many ways - aggression toward other dogs, people, animals and even toys - but the causes are relatively straightforward.
Nature All dogs have the potential for aggression.
Before dogs became our trusted companions, they had to fend for themselves - hunting for food, protecting their territory and caring for their pack.
Even after they were domesticated, dogs continued to use aggression to secure their place in the pack.
Terriers kept small animals away, Rottweilers guarded people and cattle, and Lhasa Apsos sounded the alarm in Tibet.
Nearly all dog breeds have an interesting resume, with many relying on aggression to secure their position.
While breed doesn't guarantee personality, the dog's lineage is a good indicator of the probability that he will display aggression, and his biological make-up has a significant impact on how aggressive he becomes.
Experience The dog's environment, level of socialization and life experiences directly influence his aggressiveness.
Dogs raised around dogs, kids, and animals are less likely to act aggressively, especially when they have been rewarded for good behavior.
Socializing your dog reduces his aggression; because of his positive associations toward these things he learns to enjoy (or at least tolerate) them.
In addition, dog training goes a long way toward showing him what behaviors you prefer.
When a dog is not socialized to others he is more likely to develop anxieties and become fear aggressive.
Traumatic experiences can also trigger aggression.
Any experience that scares a dog can cause him to act aggressively in the future under similar circumstances.
Medical Causes Medical issues are another cause of aggression.
The dog's health impacts his personality as well as how he feels.
A dog that is in pain or sick in some other way may lash out under circumstances that he otherwise would not.
Often when a dog turns aggressive all of a sudden, the underlying cause turns out to be a medical ailment.
Nature, experience and medical reasons are the most common causes of dog aggression.
To reduce the odds of your dog being aggressive, make sure you address each of these areas.