XIII 



THE ROLE OF SEX IN THE EVOLUTION OF MIND 



' I ^HE reason for the existence of sex is one of 

 -'- those biological problems whose solution seems 

 as remote as it did a century ago. Many remark- 

 able discoveries have been made in regard to the 

 microscopic structure and development of the germ 

 cells in both plants and animals. We have learned 

 much of the general biology of sex, and the prob- 

 able evolution of sex in the organic world. And 

 substantial progress has been made with the old 

 problem of the determination of sex. But to the 

 question, Why came there to be two sexes at all? 

 or in other words, Why do not organisms continue 

 to reproduce asexually as it is probable they once 

 did? we can only offer answers that, to say the least, 

 are very hypothetical. 



While the fact that sex is absent in the lowest 

 forms of life indicates that evolution has proceeded 

 at least a certain distance without its aid, and sug- 

 gests the possibility of the evolution of sexless forms 

 of a high degree of organization, yet the general 

 prevalence of sex, with but rare exceptions, in all 

 but the most primitive organisms points to the con- 

 clusion that sex has played a fundamental role in 



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