If you're a dog owner, you'll see your dog poop thousands of times over their life. Have you ever wondered how dogs decide where to poop?
They seem to make the decision very carefully. So what are they taking into consideration?
Several years ago, a study conducted by Czech and German researchers found that dogs prefer to poop along the north-south magnetic lines of the earth. The news was widely shared, with many in disbelief. Do dogs really poop in alignment with the earth's magnetic field?
The answer, as far as we know, is yes. The exhaustive (and probably exhausting) study, which was published in the journal Frontiers in Zoology, examined 70 dogs of 37 different breeds over two years. After observing 1,893 defecations and 5,582 urinations, researchers found that under "calm magnetic field conditions," dogs seemed to prefer to defecate "with the body being aligned along the north-south axis," and appeared to completely avoid the east-west axis.
The researchers noted that this behavior was only consistent under calm magnetic field conditions. When the earth's magnetic field was in a state of flux, which happens during events like geomagnetic storms, the dogs' behavior was less predictable.
As to why dogs would do this, we still have no idea. We don't know if they are conscious of the earth's magnetic fields and purposely align themselves along them in specific ways, or if their sensitivity to the earth's geomagnetic field exists on an unconscious level. Moreover, we don't know why this behavior would be beneficial or preferable to dogs.
Dogs also use defecation to fulfill a social purpose: They're leaving information for the next dog to find.
As you probably know, dogs have an incredible sense of smell, which they use as their primary way of gathering information. When a dog poops, they are leaving a deposit of important information, and they can't take that task lightly.
In the wild, wolves leave feces, urine, and other scent markings to mark the perimeter of their territories. These scent markings tell other wolves to stay away. Domesticated dogs, though they're far removed from their wolf ancestors, may feel a similar urge to leave these markings for other dogs to "read." As Carlo Siracusa, director of the Small Animal Behavior Service at the veterinary hospital of the University of Pennsylvania, told Bryan Gardiner at Wired, "these messages can tell your dog how many other dogs are in the immediate area, the sexual status of those dogs ... whether a particular dog is a friend or an enemy, what he or she had for lunch, and when they were last in the area."