1867.] Creation by Law. 481 



female birds are of course not placed at any disadvantage in the 

 struggle for existence by their more sombre colouring." And after 

 describing the various ornaments of these birds, he says": " Mere 

 ornament and variety of form, and these for their own sake, is the 

 only principle or rule with reference to which Creative Power 

 seems to have worked in these wonderful and beautiful birds. 



A crest of topaz is no better in the struggle for 



existence than a crest of sapphire. A frill ending in spangles of 

 the emerald is no better in the battle of life than a frill ending in 

 spangles of the ruby. A tail is not affected for the purposes of 

 flight, whether its marginal or its central feathers are decorated 



with white Mere beauty and mere variety for 



their own sake, are objects which we ourselves seek when we can 

 make the Forces of Nature subordinate to the attainment of them. 

 There seems to be no conceivable reason why we should doubt or 

 question that these are ends and aims also in the forms given to 

 living organisms."* 



Here the statement that "no connection can be conceived 

 between the splendour of the humming birds and any function 

 essential to their life;" is met by the fact that Mr. Darwin has not 

 only conceived but has shown, both by observation and reasoning, 

 how beauty of colour and form may have a direct influence on the 

 most important of all the functions of life, that of reproduction. 

 In the variations to which birds are subject, any more brilliant 

 colour than usual would be attractive to the females, and would 

 lead to the individuals so adorned leaving more than the average 

 number of offspring. Experiment and observation have shown 

 that this kind of sexual selection does actually take place, and the 

 laws of inheritance would necessarily lead to the further develop- 

 ment of any individual peculiarity that was attractive, and thus the 

 splendour of the humming birds is directly connected with their 

 very existence. It is true that " a crest of topaz may be no better 

 than a crest of sapphire," but either of these may be much better 

 than no crest at all ; and the different conditions under which the 

 parent form must have existed in different parts of its range, will 

 have determined different variations of tint, either of which were 

 advantageous. The reason why female birds are not adorned with 

 equally brilliant plumes is sufficiently clear; they would be inju- 

 rious by rendering their possessors too conspicuous during incuba- 

 tion. Survival of the fittest has therefore favoured the development 

 of those dark green tints on the upper surface of so many female 

 humming birds, which are most conducive to their protection while 

 the important functions of hatching and rearing the young are 

 being carried on. Keeping in mind the laws of multiplication, 



* 'Reign of Law,' p. 248. 



