SENSORY CAPACITIES AND INTELLIGENCE OF DOGS 



*5 



gence we should expect the latter to be 

 more adept in the manipulation of knobs, 

 sticks, strings, and the like, because of his 

 well developed hand. Perhaps if monkeys 

 and dogs were tested on a similar maze, 

 where the responses involve only loco- 

 motion, the standing of the two forms 

 would be reversed. We have no way of 

 knowing, however, for this has not been 

 done. Similarly, the only demonstration 

 of the raccoon's superiority to the dog 

 has been on a problem box involving man- 

 ual manipulation. The raccoon's fore- 

 paw is modified so as to be fairly efficient 

 in grasping articles. The dog's paw is, 

 of course, ill suited for such uses and, as a 

 matter of fact, a dog often prefers to use 

 his mouth. Dogs have shown very little 

 ability to imitate each other or man, but 

 this lack does not place them below other 

 animals, since experimentation has shown 

 that true imitation is rarely found in any 

 animal form, even among the higher 

 apes. 



A few words on the dog as a psychologi- 

 cal subject may not be out of place. As is 

 well known the rodents are represented 

 in behavior studies by the white rat. 

 The selection of a single representative 

 species upon which all experimenters 

 iuterested in the lower mammals should 

 do systematic work is, of course, a great 

 advantage, since it renders possible the 

 collation and comparison of a vast amount 

 of data. If some workers used squirrels, 

 others guinea-pigs, others weasels and so 

 on, this valuable intercomparison would 

 scarcely be possible. Among the Car- 

 nivora there has not been such a definite 

 concentration upon a single form, al- 

 though the dog has been the chief object 

 of study. There are a number of reasons 

 why the dog would seem to be the logical 

 animal to represent this group. In the 

 first place more is already known of his 

 sensory and learning capacities than of 



those of the cat, the raccoon, the porcu- 

 pine, or any of the other animals of this 

 group which have been subjected tO' 

 experimentation. In the second place 

 less interference by emotional disturbance 

 is encountered in the case of the dog than 

 in animals not so able to adapt themselves 

 to the necessary experimental situation. 

 That the emotional status of the animal 

 during testing is highly important and 

 should be kept as constant as possible 

 does not seem to be sufficiently recognized. 

 This is especially true of the higher, more 

 complex forms. We cannot blame pio- 

 neers for having tested animals under 

 conditions rendering them more or less 

 frantic with hunger and fear. But it 

 seems surprising that such a recent worker 

 as Williams (56) should take seriously 

 his negative results on form discrimination 

 in dogs when his subjects were, judging 

 from his descriptions, highly nervous and 

 fearful during the tests. To quote: 

 " . . . .a dog occasionally develops 

 the obsession that he can not get out of 

 the blind alley and stands yelping, en- 

 during for a time the punishment (electric 

 shock). In such a situation it may be 

 necessary to move up the secondary coil 

 thus making the electric current stronger 

 till it is of sufficient intensity to overcome 

 the obsession and force the dog to become 

 more diligent in search of a way out." 

 Williams used punishment only. To 

 quote again: "With the method of pun- 

 ishment by electric shocks, little time need 

 be wasted, if all parts of the apparatus are 

 in good working order, as the animal can 

 be forced by the shocks to move to any 

 part of the apparatus at the will of the 

 operator." No doubt such an investi- 

 gator would consider it a waste of time 

 to become sufficiently en rapport with the 

 dog to permit the use of the normally 

 strong desire of a dog to please his master 

 as motivation. 



