GONADAL HORMONES AND SOCIAL BEHAVIOR 



1255 



differentially to the hormone or that females 

 do not provide as adequate a stimulus for 

 aggressive responses as do males. 



Increase in the social status of androgen- 

 treated individuals has been recorded for 

 chickens (Allee, Collias and Lutherman, 

 1939; Douglis, 1948), mice (Beeman, 1947), 

 and chimpanzees (Clark and Birch, 1945; 

 Birch and Clark, 1946). However, three 

 males of free-living valley quail which re- 

 ceived pellets of testosterone propionate be- 

 came pugnacious toward other males but 

 failed to alter their positions in the peck- 

 order of the covey (Emlen and Lorenz, 

 1942). Hens receiving androgen also failed 

 to rise in the social order (Williams and 

 McGibbon, 1956) . In both of these instances 

 the group remained intact, and presumably 

 the social habits withstood the influence of 

 lowered thresholds for aggressive action 

 l^'oduced by the androgen. These results 

 differ from those obtained by Allee, Collias 

 and Lutherman (1939), as did the proce- 

 dure, because in the latter experiment pair 

 contests were conducted between individuals 

 of different flocks containing the treated 

 birds. It is possible that a treated hen, if 

 promptly returned to her flock from an ini- 

 tial encounter (which she usually won) , was 

 still highly stimulated, and if she engaged 

 in fighting with a threatening superior pen- 

 mate, a reversal of dominance would occur. 



An experiment which is the converse of 

 those described above has recently been 

 performed, but not previously reported, by 

 Robert Buchholz of Kansas State Univer- 

 sity. He attempted to determine whether a 

 low ranking bird could be made the domi- 

 nant individual in the flock by varying the 

 psychologic state rather than by treatment 

 with androgen. The chickens used were 

 males which had been reared together. The 

 lowest ranking bird, which had never been 

 observed to peck a penmate, was selected 

 for experimentation. When 11 weeks old, 7 

 birds were isolated for 33 days to extinguish 

 the memory of past associations. When ap- 

 proximately 16 weeks old, the lowest rank- 

 ing male was placed into a pen for 1 week 

 to give him the advantage associated with 

 prior residence. When a female was added 

 he dominated her without any difficulty. 

 After 2 days she was removed and a former 



penmate, which was immediately above him 

 in rank previously, was introduced. The 

 formerly subordinate male gained domi- 

 nance over him and all of his other former 

 penmates which were introduced during the 

 course of 1 day in the reverse of the former 

 peck-order. By this method the original 

 lowest ranking male became the top ranked 

 bird. It is apparent that the chicken as well 

 as the mouse (Ginsburg and Allee, 1942) is 

 a species in which psychologic factors can 

 be instrumental in the attainment of a state 

 that formerly would have been thought of 

 as solely the consequence of hormonal ac- 

 tion. 



Changes in agonistic behavior after the 

 cessation of hormonal treatment have been 

 investigated. Birch and Clark (1946) noted 

 a reversal of dominance to the pretreatment 

 status in adult ovariectomized chimpanzees, 

 whether they were given methyl testosterone 

 or estradiol. In ringdoves Bennett (1940) 

 also found a tendency of previously treated 

 birds to return to their former social rank. 

 However, Allee, Collias and Lutherman 

 (1939) reported that the social position 

 which treated hens won persisted as long as 

 these flocks were under observation. These 

 contrasting results on the two species of 

 birds may perhaps be explained on the basis 

 of qualitative differences in the social in- 

 ertia of these species. In the peck-right sys- 

 tem found in chickens, repeated pecking re- 

 inforces the unidirectional pecking and 

 maintains dominance relations, whereas the 

 bidirectional pecking characteristic of doves 

 results in a more fluid social order. Thus, 

 the relative permanence of social gains or 

 losses induced by exogenous hormone may 

 be influenced, among other factors, by the 

 type of social behavior patterns peculiar to 

 the species. 



C. ESTROGENS AND SUBMISSIVENESS 



The reports that have been made follow- 

 ing observations and experiments on the re- 

 lationship between estrogens and the social 

 order have resulted in a confused picture. 

 There are species such as the red-necked 

 ])halarope, Phalaropus lobatus, in which the 

 female in the reproductive phase is the more 

 colorful, sings, fights, and entices the male 

 (Tinbergen, 1935) . But in the case of many 



