1 88 THE FUNCTION OF SEX 



more than the effect or function of conjugation)- Manifestly they 

 have no bearing on such problems as progression, retrogression, 

 recapitulation, variability, the causation of variations, the dis- 

 tinction between characters, and the rest we have discussed. 

 They merely attempt to describe the way in which parental 

 characters are distributed amongst offspring and descendants 

 under conditions of conjugation. To parthenogenesis they do not 

 apply ; for here, since no allelomorphs meet, none can be dominant 

 or recessive, none can segregate. In fact, they apply to no 

 problem that is presented in common by parthenogenetic and 

 conjugating species. At any rate I can think of none ; and though 

 I have inquired industriously amongst the adherents of " the new 

 science of genetics," I have quite failed to secure enlightenment. 2 



310. It has been said, indeed, that since "the rule that all 

 organisms pass through a sexual cycle at some period of their 

 existence has extremely few exceptions," 3 all problems of biology 

 are problems of conjugation. It would be as reasonable to declare 

 that, since all organisms die, therefore all problems of biology are 

 problems of death. Such a statement is merely equivalent to a 

 declaration that the universe is a unity, the facts and laws of 

 which are related. Again, it has been said, " It is the claim of the 

 Mendelians that they have discovered in certain cases some of the 

 fundamental characters of an organism the units of hereditary 

 transmission, which are represented in the reproductive cells by 

 definite entities known as allelomorphs.' 4 But, obviously, if there 

 is no segregation, but merely patency and latency, the discovery 

 has not been made. In this instance, also, it would be well if the 

 reader paused and asked himself, not whether Mendelism solves 

 any problems, but whether it has a conceivable bearing on any 

 problem save that of conjugation of sex. 



311. We saw that individuals of sexually dimorphic species 

 have two sets of sexual characters, one of which is patent 

 and the other latent, one of which is dominant and the other 



1 Of course every effect is not necessarily a function. A function is that which 

 bestows utility. One effect of sex is to halve the possible number of offspring. 

 But no one will believe that this halving is the function of sex. Besides, nature 

 is able by the selection of fertility to increase the number of offspring produced by 

 a pair up to any useful limit, and so obviate this effect. On the other hand, if, 

 as Mendelians suppose, bi-parental reproduction mixes parental characters as 

 marbles are mixed, but leaves them otherwise unchanged, it would seem we have 

 no alternative but to suppose that such mixing is both the effect and the actual 

 function of sex. I think it is impossible to imagine any other function. 



2 See, for example, Nature, 3rd Oct. 1907 to Jan. 23rd 1908. 



8 R, H. Lock, Nature, Nov. I4th, 1907. * Op. cit., Nov. I4th, 1907. 



