HORMONES AND MATING BEHAVIOR 



1223 



with respect to the role of gonadal hormones 

 in the development and expression of mating 

 behavior was long ago stated by Zucker- 

 man and Parkes (1939) in another context: 

 "Androgen stimulation induces the two main 

 types of change. The first leads to assump- 

 tion of permanent characters, the second 

 to the assumption of characters which disap- 

 pear when androgen stimulation ceases." 



Their thought was of secondary sexual 

 characters, of genital tract structure, and, 

 we would guess, only incidentally of be- 

 havior. Twenty years later we may go 

 further than the data available to them 

 permitted and extend the hypothesis to 

 the tissues mediating mating behavior. We 

 would direct attention to the possibility 

 that in these tissues the same rules apply, 

 but, in addition to hormonal (and genetical) 

 factors, psychologic factors have appeared, 

 and, as animals have evolved, a picture has 

 been created in which there is a mingling 

 and in some way an interaction of all these 

 factors. Elucidation of the manner in which 

 this occurs and its extent will depend on 

 the continued effort of investigators from 

 many disciplines. 



A final remark has to do with an aspect 

 of the subject that has not had treatment 

 in the present review. The discussion up to 

 this point has dealt principally with mating 

 behavior, that restricted part of the total be- 

 havior which subserves reproduction more 

 directly than it does any other vital ac- 

 tivity. However, as investigations have pro- 

 ceeded, it has become apparent that the 

 action of the gonadal hormones is much 

 broader than we realized years ago when 

 attention was first being focused on the re- 

 lationship of these substances to mating be- 

 havior. The fact will be apparent from what 

 has been written about the role of these 

 substances in parental behavior (chapter 

 by Lehrman) and in social behavior (chap- 

 ter by Guhl). Recent work suggests that 

 this concept may be extended even further. 

 Not all the behavior associated with the 

 male or the female is reproductive. Many 

 differences between the behavior of males 

 and females have been described, and many 

 more are a part of the cultural lore. The 

 .subject is too vast for review here, but two 

 exami)les will be mentioned. The male chim- 



l^anzee is said to be a fighter and a bluffer, 

 the female is treacherous and more difficult 

 than the male to bluff consistently (Yerkes, 

 1943; Hebb, 1946). Differences between the 

 sexes are seen in the play configuration of 

 preadolescent children (Erikson, 1951). In 

 their chapter in this book, Hampson and 

 Hampson have discussed this "psychologic 

 sex" and suggested that it "does not have 

 an innate, preformed instinctive basis as 

 some have maintained," but rather is "un- 

 differentiated at birth ... a sexual neutrality 

 in the place of the Freudian bisexuality . . . 

 and that the individual becomes differenti- 

 ated as masculine or feminine, psychologi- 

 cally, in the course of the many experiences 

 of growing up." 



As evidence has accumulated (Burns, 

 1942, 1949, and his chapter in this book; 

 Jost, 1947, 1953, 1957; Wells, Cavanaugh 

 and Maxwell, 1954) that the fetal gonad 

 (probably the testis rather than the ovary) 

 is the source of a hormone with androgenic 

 properties, investigators have asked if the 

 action of this substance may not extend 

 beyond the genital tract and tissues mediat- 

 ing mating behavior, to the "behavior be- 

 yond that which is purely sexual" (Phoenix, 

 Goy, Gerall and Young, 1959). Undoubt- 

 edly this hypothesis will soon be tested. If 

 it is found to be true, an unsuspected action 

 of the gonadal hormones will have been re- 

 vealed, an action, we predict, that will be 

 a bond between the work of the experi- 

 mental embryologists who have concerned 

 themselves so completely with all that is in- 

 volved in the development and differentia- 

 tion of the genital tracts, and the work of 

 the psychologists and psychiatrists for 

 whom the development and differentiation 

 of neural tissues presents problems of equal 

 interest and importance. In addition, a big 

 circle will have been completed. Analysis of 

 sexual differentiation during the embryonic 

 and fetal periods began with the work of 

 the experimental embryologists, much of 

 which is reviewed in Editions 1 and 2 of 

 Sex and Internal Secretions. A segment of 

 the work reviewed in this chapter was 

 started in that atmosphere, and attention 

 is directed to the fact that, once the basis 

 was established, much of the conceptualiza- 

 tion outlined here developed from the in- 



