DARWIN 



seems likely, the process would be useless and fre- 

 quently harmful to the species and this would be 

 counteracted by natural selection. While there are a 

 relatively small number of cases where the females 

 seem to choose mates after a competitive trial of the 

 males, the predominating factor in mating is chance 

 propinquity. 



We must endow animals and insects with our high- 

 ly developed aesthetic and other emotional attrib- 

 utes, and it is altogether improbable that the gorgeous 

 colours of insects can excite such emotions in an organ- 

 ism of so low a mental development. One of the com- 

 monest factors in sexual attraction is noise; we can 

 hardly coordinate ability to make the loudest sound 

 with other superior qualities in the cricket, especially 

 as the loudest cricket is the one nearest the female. 

 Mayer and Soule have painted the wings of butter- 

 flies different colours and even put male wings on fe- 

 males, and vice versa, and found no difference in 

 breeding. The colours in moths, which breed at night, 

 are as lovely as those of butterflies and Fabre has 

 proved that the male moths are attracted, in all prob- 

 ability, to the females by odour; if so, propinquity 

 and the direction of the wind become the determining 

 factors. Lastly, the vivid colouration of male fish at 

 the breeding season is pronounced, and yet the female 

 fish does not even see the particular male, which fer- 

 tilizes her eggs. Delage sums up the evidence as fol- 

 lows: "Although the theory of sexual selection is to 



C 233 3 



