794 THE DESCENT OF MAN 



unclianged, we can distinctly trace how simple spots with 

 a little fulvous shading on one side may have been devel- 

 oped by small steps into the wonderful ball-and-socket or- 

 naments; and it is probable that they were actually thus 

 developed. 



Every one who admits the principle of evolution, and 

 yet feels great difficulty in admitting that female mammals, 

 birds, reptiles, and fish could have acquired the high taste 

 implied by the beauty of the males, and which generally 

 coincides with our, own standard, should reflect that the 

 nerve cells of the brain in the highest as well as in the 

 lowest members of the Vertebrate series, are derived from 

 those of the common progenitor of this great Kingdom. 

 For we can thus see how it has come to pass that certain 

 mental faculties, in various and widely distinct groups of 

 animals, have been developed in nearly the same manner 

 and to nearly the . same degree. ' 



it The reader who has taken the trouble to go through the 

 several chapters devoted to sexual selection will be able to 

 judge how far the conclusions at which I have arrived are 

 supported by sufficient evidence. If he accepts these con- 

 clusions, he may, I think, safely extend them to mankind; 

 but it would be superfluous here to repeat what I have so 

 lately said on the manner in which sexual selection appar- 

 ently has acted on man, both on the male and female side, 

 causing the two sexes to differ in body and mind, and the 

 several races to differ from each other in various characters, 

 as well as from their ancient and lowly organized progenitors. 



He who admits the principle of sexual selection will be 

 led to the remarkable conclusion that the nervous system 

 not only regulates most of the existing functions of the body, 

 but has indirectly influenced the progressive development 

 of various bodily structures and of certain mental quali- 

 ties. Courage, pugnacity, perseverance, strength and size 

 of body, weapons of all kinds, musical organs, both vocal 

 and instrumental, bright colors and ornamental appendages, 

 have all been indirectly gained by the one sex or the other, 



