It is difficult at times to draw a line in the twilight zone between acts which arise out of pure intelligence on the part of the dog and acts which arise out of the dog’s ability to learn by repetition. Trick work for instance is learned by repetition rather than by intelligence.
We have stated that environment as duplicated in the dog’s memory is the chief source of his information which in turn he translates into acts. The five common senses of the dog can be placed in order of importance in communication as smell, hearing, sight, touch, taste.
First, sight; we have long maintained that dogs are mostly color blind and we have been condemned soundly for the opinion. It is likely that all the external world appears to them as varying highlights of black and gray.
Dogs are not certain about colors. First, they do not have the opportunity to see colors on account of their height as does the human; secondly, humans by use of names learn to distinguish between colors whereas they would not be nearly as able to distinguish if they judged entirely the colors without names.
Dogs cannot see as far distant as can humans. Moving objects are seen more quickly by the dog than by humans. Some of this may be due to the fact that be is always watching for something to happen rather than because he has keener eyesight. Also because the dog is horizontal in his plane of body whereas the human is vertical he sees less and sees at closer range.
For this same reason, dogs are not particularly object minded. You can try the experiment with your own dog. Slip into the yard or kennel house, stand perfectly still, make no sound, the wind blowing against you and from the dog. In most cases your own dog does not recognize you; be barks at you as tho you were an intruder. If you walk, if he hears your voice, or if he scents you, of course he recognizes you instantly.
The nose. The sense of smell in the dog is the most developed sense, developed far ahead of smell in the human; it must be considered as being based not upon any discrimination in flavors or odors but into a general classification of smells useful and useless, or friendly and dangerous.
Memory of smell is strong in the dog and his mind will recall an object more quickly by the nose than by the eye.
Most of our tastes and smells insofar as the human is concerned have been developed thru education. For instance, perfumes usually are distasteful to the dog whereas rotting meat he sniffs joyously.
Smells associated with animals and with food are quickly discerned by the dog; they are useful smells, useful in satisfying his hungry stomach or in protecting him against danger.
The first sense of the dog to be developed is the suckling instinct and smell. Its eyes are closed for about nine days after birth. The nose is really the guiding member for the puppy. This ability to smell keenly, to be guided by scent, is developed constantly in the dog and becomes more determining than eyes and ears.
Dogs of good nose or strong scenting ability, usually are loyal and affectionate with their masters. They can more easily determine identity; they become more attached to the scent of the master and his family.
In taste, the dog has not developed variety. He can be taught to like almost any taste whether it is evil-tasting or agreeably-tasting. This must be borne in mind in connection with the overfeeding and the wrong feeding of dogs.
The hearing of the dog can be developed considerably and the dog uses it often. A dog can hear considerably thru vibrations into the body. Thus a deaf dog can be an alert watch dog. Also a dog need not use sight in certain instances so much as does the human for he can detect danger thru the ear.
The sense of touch has little development in the dog because it is little needed. The hairy covering of his entire body except nose, makes its use almost impossible. Further, as with all wild animals, distance gives the greatest safety and the animal that employs touch never repeats for its enemy has struck.