i6 



THE QUARTERLY REVIEW OF BIOLOGY 



This brings us to the third qualification 

 of the dog which renders it capable of 

 becoming an ideal laboratory subject. 

 The dog is unquestionably more sensitive 

 to the whims of a man who has won his 

 confidence than is any other carnivore, or 

 perhaps any other infra-human animal, 

 for that matter. The cat, for example, 

 is scarcely at all dominated by man, 

 except in his role as provider. Thus 

 starving or using some such punishment 

 as electric shock is practically necessary 

 to produce sufficient motivation to insure 

 their attacking laboratory problems. 

 Even in monkeys and apes the problem of 

 motivation is a difficult one if we may 

 judge from reports in the literature. The 

 dog has continually demonstrated his 

 ability to adapt himself readily to the 

 wide variety of conditions which man 

 has imposed upon him. He has cooper- 

 ated with man in war and in peace, in the 

 forests, in pastures, and in the city. Nor 

 has he failed to cooperate even in the 

 psychological laboratory except when no 

 effort has been made to deal with him in a 

 manner befitting his high degree of com- 

 plexity and sensitivity. Many examples 

 might be given to show his willingness 

 to play his part in experimental situations 

 in the absence of harsh forms of motiva- 

 tion. The dogs used in the Leningrad 

 laboratory are said to jump up onto the 

 experimental tables without command 

 and to lift up their feet one at a time to 

 permit the adjustment of the necessary 

 harness. An early study of Hamilton's 

 on a young bull terrier (14) gives an ad- 

 mirable instance of adjustment to an 

 experimental situation. The problem pre- 

 sented to the dog was an extremely 

 difficult one, that of releasing himself 

 from a box by the manipulation of a 

 system of pedals. This dog worked daily 

 on the problem over a period of many 

 weeks with, apparently, unflagging zeal 



even though no punishment was used and 

 the reward consisted not of food but only 

 of petting and a few kind words. It 

 seems only reasonable to suppose that an 

 animal working under natural and un- 

 disturbing conditions would be more 

 nearly capable of giving a performance 

 record, whether of discrimination or of 

 learning, that would represent its maxi- 

 mum capacity than would an animal 

 working under the stress of punishment or 

 too severe hunger. The dog is one of the 

 few animals which will work without 

 such motivation. 



One of the reasons for the discrepancies 

 that exist among experimenters on the 

 dog's capacities is no doubt the fact that 

 all sizes and sorts of dogs have been used 

 from highly bred bull terriers to an assort- 

 ment of mongrels. It would no doubt be 

 well to settle upon a representative breed 

 for systematic experimentation, but the 

 writers are at present in no position to 

 make a definite proposal as to which of the 

 many breeds is best suited to the purpose. 



II. RECENT TESTS OF THE ABILITY OP 

 "FELLOW" TO RESPOND TO VERBAL STIMULI 

 (OR TO UNDERSTAND HUMAN LANGUAGE) 



Fellow is a thoroughbred German 

 Shepherd male, between 4 and 5 years of 

 age, with a long line of famous blooded 

 ancestry behind him, and owned by Mr. 

 Jacob Herbert of Detroit, Michigan. 

 Mr. Herbert has made a hobby of fine dogs 

 for years and selected Fellow from among 

 scores that he has bred, and sought to 

 teach him in various ways to understand 

 human language in the sense of responding 

 in the appropriate manner to commands. 

 This type of training is, of course, not 

 especially new. The verbal cue has been 

 often employed in professionally trained 

 animals, and everyone has taught his dog 

 to do, upon proper command, a few tricks. 

 £t least. But Fellow, as Mr. Herbert 



