How dogs communicate by smell

Dogs rely heavily on their acute sense of smell to communicate with each other by means of "scent messages." There are many advantages to using scent messages, one of the most important being that they last for longer periods of time. So it is possible by means of these messages for dogs to communicate with each other without ever even seeing one another. These types of "scent messages" can remain within the air for a certain amount of time and it's really handy for dogs that live in vegetation areas where immediate visibility isn't so good and therefore visual communication isn't as effective. Dogs have two different types of olfactory communication that they use: one is through their feces and urine, and the other is the dog's body odor that it impregnates onto places by means of the dog's glandular secretions.

Dog feces and urine: All animals use their feces and urine to "mark" their territory, what this really means is that they want other dogs to know the confines of their territory as well as their social status. It seems that dogs defecate more when they are off the leash and when their owner isn't around; the motivation for this behavior is still unclear and it certainly does not apply to all dogs. One of the evident behaviors that dogs have is that they lift their leg to urinate; a dominating dog lifts his leg a lot higher than those "under" him and it is also possible that a female dog will behave this way too. When a dog lifts his leg up high, even if he doesn't urinate, it means he is showing his dominance over the other dogs that are watching. Another very typical thing dogs do is urinate over a place that another dog has already urinated on. You may have also noticed how dogs dig at the ground with their back legs when they have just finished doing their needs; there are actually several different reasons for this behavior that include smell, one could be that the dog is trying to spread his smell more, another reason could be that he is trying to leave more of his scent on his feces (since there are a lot of glands located on the paws), or he may be letting the dogs know that he has just defecated in that spot.