Why do dogs have to pee against the pillar is the original reason?

Why do dogs pee against a post Dogs pee against a post because they want to mark, it is also the nature of dogs, the purpose of male dogs is usually to attract female dogs through the scent and signal they leave behind. On the other hand, when the dog smells other dogs when it defecates, it will rush to pee in as large an area as possible to cover other dogs and inform other canines that this place belongs to me.