HEREDITY OF SAVAGENESS AND WILDNESS 287 



No. of rat Date Savageness Wildness Timidity 



59c? Jan. 10 4 4 3 



"17 4 3 2 



69$ "10 3 3 4 



"17 2 3 4 



63? "10 3 3 4 



"17 3 3 3 



The preliminary analysis of the behavior of rats, and my 

 measurements, convinced me that I might profitably under- 

 take a systematic study of savageness, wildness, and timidity 

 in wild, tame, and hybrid individuals. Of these three traits, or 

 possibly I should say, combinations of traits, timidity is the 

 most difficult to recognize and satisfactorily measure. It is 

 indeed extremely doubtful whether it can with sufficient cer- 

 tainty be distinguished from wildness to render measurements 

 significant. I have attempted, however, throughout the inves- 

 tigation, to measure it and I shall report the results along with 

 those for the other traits. 



My method of testing the rats was to place a cage containing 

 individuals to be examined on a table in the center of an other- 

 wise unoccupied room. I then removed an individual from the 

 cage in order carefully to observe its behavior. This removal 

 was effected by means of my gloved hand, when that method 

 could safely be used, or, in the case of extremely savage animals, 

 by means of a pair of placental forceps which were used to 

 grasp the animal by the tail. 



The chief indications of savageness noted and relied upon as 

 a basis for grading are (i) biting; (2) exposing or gnashing 

 the teeth; (3) jumping at hand or forceps; (4) squeaking. 



Similarly, the chief indications of wildness are (1) attempts 

 to hide from view in cage or in hand; (2) random and excited 

 running about in the cage or excited attempts to escape from 

 the hand or the forceps; (3) squeaking; (4) urination and 

 defecation. 



Timidity is indicated (1) by attempts to avoid the experi- 

 menter; (2) by a kind of chattering or gnashing of the teeth; 

 (3) by cowering and what looks like trembling; (4) urination 

 and defecation. 



From my notes, I reproduce the following statements con- 

 cerning these several traits of behavior. " Savageness is of two 



