242 THE DESCENT OF MAN. 



seen, are generally ready to breed before the females; the 

 strongest, and with some species the best armed of the 

 males, drive away the weaker; and the former would then 

 unite with the more vigorous and better-nourished females, 

 because they are the first to breed.* Such vigorous pairs 

 would surely rear a larger number of offspring than the 

 retarded females, which would be compelled to unite with 

 the conquered and less powerful males, supposing the sexes 

 to be numerically equal; and this is all that is wanted to 

 add, in the course of successive generations, to the size, 

 strength and courage of the males, or to improve their 

 weapons. 



But in very many cases the males which conquer their 

 rivals do not obtain possession of the females, independently 

 of the choice of the latter. The courtship of animals is 

 by no means so simple and short an affair as might be 

 thought. The females are most excited by, or prefer pair- 

 ing with, the more ornamented males, or those which are 

 the best songsters, or play the best antics; but it is obviously 

 probable that they would at the same time prefer the more 

 vigorous and lively males, and this has in some cases been 

 confirmed by the actual observation, f Thus the more 

 vigorous females, which are the first to breed, will have the 

 choice of many males; and though they may not always 

 select the strongest or best armed, they will select those 

 which are vigorous and well armed, and in other respects 

 the most attractive. Both sexes, therefore, of such early 

 pairs would, as above explained, have an advantage over 

 others in rearing offspring ; and this apparently has 

 sufficed during a long course of generations to add not 



inals and Winter Birds of E. Florida," p. 229) of the later broods 

 after the accidental destruction of the first, says that these " are found 

 to be smaller and paler-colored than those hatched earlier in the sea- 

 son. In cases where several broods are reared each year, as a general 

 rule the birds of the earlier broods seem in all respects the most per- 

 fect and vigorous." 



* Hermann Miiller has come to this same conclusion with respect 

 to those female bees which are the first to emerge from the pupa each 

 year. See his remarkable essay, "Anwendung den Darwin'schen 

 Lehre auf Bienen," " Verh. d. V. Jahrg.," xxix, p. 45. 



f With respect to poultry, I have received information, hereafter to 

 be given, to this effect. Even with birds, such as pigeons, which 

 pair for life, the female, as I hear from Mr. Jenner Weir, will desert 

 her mate if he is injured or grows weak. 



