54 A. H. Hamer 



Territorialism and " Sexual Selection.** 

 By A. H. Hamer. 



Anyone who tries to keep a number of birds together without 

 regard to species, even in a large aviary, will soon find he is in 

 for trouble. He will find it impossible to keep more than one 

 male of certain species at any time of the year and at breeding 

 seasons more species will develop the same fault. There will 

 have to be a process of elimination and certain "pugnacious little 

 brutes" will have to be taken out. What will have happened 

 when peace is restored is that he will have eliminated or reduced 

 to one male each of the territorial species and his main stock will 

 consist of non-territorials. This seems simple enough, but the 

 matter is seldom referred to in a manner which seems to show a 

 true appreciation of the problem. Certain species are dubbed 

 ** pugnacious " and it seems to be supposed that they revel in 

 fighting for fighting's sake. There is no fighting for fighting's sake 

 in Nature, however, and much less fighting of any sort than is 

 popularly supposed. The male sun-birds, say, which you have 

 included in your aviary, fight because their instinct compels each 

 to try to keep a certain radius of territory clear of other mature 

 males of the same species. The fighting will be ultimately 

 disastrous to the weaker in the aviary, if they are not removed, 

 simply because they are artificially prevented from accepting the 

 logic of facts and clearing out. In a state of nature the inter- 

 loper would retire at the first dash of the rightful owner and there 

 would not be a set batde to decide which was the stronger^ 

 neither would the bird in possession pursue the other beyond his 

 radius for the sake of a fight. A fairer and better description of 

 his character is therefore "territorial," rather than "pugnacious.** 



That Nature desires to minimise real fighting is seen by the im- 

 mense proportion of disputes which are settled orally, so to 

 speak, or by a display of threatening attitude re-inforced perhaps 

 by special devices such as crests or inflations (A). 



