The dog's ears flap in the breeze, and the expression on its face suggests that sticking its nose in the wind is the canine equivalent of heaven. Still, there's something about this sight that raises a couple of questions. The answer to the first question comes from Jack Papp, the obedience trainer and owner of Papp's Dog Service in Akron, Ohio. Papp said the key to understanding this particular bit of dog behavior is to remember that the canine nose is much more sensitive than those found in the middle of the human face. People laugh when I say this, but it simply gives the dog pleasure.
Dogs are the same way, only more so because their sense of smell is so much more developed.
While the human nose has about 5 million aroma receptors embedded in a piece of nasal tissue the size of a postage stamp, some dogs have more than 200 million receptors in a sheet of tissue folded inside their noses. Unfolded, the nasal tissue would be big enough to cover one-third of the dog's surface area. At the back of each dog's mouth is an extra olfactory organ called Jacobson's organ, which is connected to the nasal cavity by air ducts. The organ seems to give dogs the ability to more precisely distinguish among odors. Think of it as an olfactory turbocharger.