REED WARBLER 



were no commingling of the colours as a result of amphimixis 

 and that, consequently, a dull-coloured female could not 

 directly influence the colour of the male offspring, yet this 

 would not affect the issue, for vitality must react upon the 

 colour and influence the growth of the secondary sexual 

 characters. Evidence of this can be seen in our domestic 

 animal's, and to some extent even in ourselves. A dog in a 

 low condition of health loses the brilliancy of the colouring in 

 its coat, and, as is well known, the colouring of the human 

 hair is affected by ill-health. But if a law of battle obtains 

 amongst the females, we need no further explanation as to 

 how the standard of efficiency has been maintained through 

 numberless generations. 



We have discussed the meaning of a territory to the 

 individual, and have come to the conclusion that it is the 

 attainment of reproduction ; but inasmuch as this same result 

 could be gained equally as well without all the complications 

 introduced by a territory, it is evident that by this means 

 some larger purpose is being fulfilled. That a breeding terri- 

 tory is of immense importance we can infer from the fact that 

 we find the individuals of such widely separated species as the 

 Falcons, Warblers, and the Moorhen struggling for possession. 

 For my part I believe that the question of food supply has 

 been one of the determining factors, although there are two 

 observable facts which are somewhat opposed to this view. 

 Firstly, that the members of any one of those species referred 

 to, while objecting so strongly to a member of their own 

 species breeding in their territory, frequently ignore the pres- 

 ence of one of another species, no matter how closely allied 

 it may be, and no matter whether it would require a similar 

 food ; and, secondly, that there are a number of species that 

 breed in communities. But upon further consideration these 

 difficulties will be found to disappear to a great extent. It is 

 true that in Nature we can find more than one species, requir- 

 ing similar food, inhabiting the same small area of ground- 

 But supposing the law of territory were temporarily suspended, 



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