HORMONES AND MATING BEHAVIOR 



1213 



(Peterson and Young, 1955j the mean rate 

 of oxygen consumption of male guinea pigs 

 exposed to cold was 77.3 cc. per 100 gm. 

 body weight per hour whereas that of males 

 kept at room temperature was 52.0, but 

 the difference in mating behavior scores was 

 not significant. Clearly in these experiments 

 a considerable change in oxygen consump- 

 tion was not accompanied by changes in 

 sexual behavior. 



Under other conditions, a relationship 

 was found between the rate of oxygen con- 

 sumption and the amount of sexual be- 

 havior. When males were given daily tests 

 of sexual vigor the oxygen consumption 

 of animals in 3 of 4 strains correlated sig- 

 nificantly with sexual behavior (Riss, 1955). 

 On the other hand, when the oxygen con- 

 sumption of the fourth strain was elevated 

 to a point approximating that of the strain 

 having the highest rate, sexual behavior did 

 not increase proportionately. In a subse- 

 quent experiment the rate of energy output 

 was elevated by a change from isola- 

 tion to unisexual group-living and the in- 

 tensity of the sexual response increased cor- 

 respondingly (Riss and Goy, 1957) . As 

 before, the extent of the effect was limited 

 by the nature of the animal. No assumptions 

 were made concerning the physiologic mean- 

 ing of the relationship between the rate of 

 oxygen consumption and the strength of 

 sexual behavior. The increased energy out- 

 put may have permitted the change in ac- 

 tivity, but there is no evidence that it was 

 i:)rimary to the change. 



F. THE SOMATIC FACTOR AND MATING 

 BEHAVIOR 



When the data bearing on the hormonal 

 regulation of mating behavior in the male 

 and female were being reviewed attention 

 was directed to evidence for the conclusion 

 that the character of the behavior induced 

 by gonadal hormones is determined in a 

 large part by the nature of the soma or 

 substrate® on which the hormones act. Ad- 



"In this review and in other discussions of the 

 subject by the author and his associates soma 

 or substrate is used in the sense of all the tissues 

 mediating sexual behavior. The capacity for re- 

 sponse to hormonal stimulation is assumed to be 

 a function of the character of those tissues, 

 however it is determined. 



ditional evidence is provided by the many 

 studies revealing the difficulty of inducing 

 the behavior of the opposite sex by the 

 administration of heterosexual hormones 

 (p. 1198). 



The principle seems first to have been 

 stated by Goodale (1918), who was im- 

 pressed by the failure of ovaries implanted 

 into capons to feminize their behavior and 

 he wrote, "the character of the sexual re- 

 actions seems to depend upon the sub- 

 stratum, while the gonad merely determines 

 that it shall be given expression." State- 

 ment of the principle was also made or at 

 least implied following the discovery that 

 there is no constant relationship between 

 the concentration of gonadal hormone and 

 the amount of running activity in male 

 rats (Heller, 1932), after investigations of 

 the effects of heterosexual hormones on be- 

 havior (Ball, 1937a; Beach, 1941, 1942d), 

 following efforts to correlate the ovarian 

 condition and follicular development with 

 mating behavior (Young, Dempsey, Myers 

 and Hagquist, 1938), following the dem- 

 onstration that individual differences in 

 behavior before gonadectomy persisted 

 throughout an experimental period when all 

 the animals received the same hormonal 

 treatment (Boling, Young and Dempsey, 

 1938; Boling, Blandau, Rundlett and Young, 

 1941; Young and Fish, 1945; Beach and 

 Holz-Tucker, 1949; Grunt and Young, 

 1952b ) , and after observations that varied 

 behavioral patterns were displayed by male 

 rats in which there was no evidence of dif- 

 ferences in the secretion of testicular andro- 

 gens (Soulairac, 1950). Extension of the 

 l^rinciple to tissues other than those mediat- 

 ing behavior is indicated by the substance 

 of many articles reviewed by Hamilton 

 (1948). 



We dwell on tlie relationship between the 

 character of the substrate and the pattern 

 of behavior because the former as a deter- 

 minant of the latter has much to do with 

 the consistency with which the differences 

 between individuals are displayed and with 

 the circumstance that the same hormone 

 given to different animals in the same 

 amounts brings out such different patterns 

 of behavior. It follows that identification of 

 factors modifying the substrate or soma 



