96 DISPOSITION TO DEFEND THE TERRITORY 



injury inflicted. It is necessary to bear this in 

 mind, because it is held by some, who have 

 carefully observed the actions of various species, 

 that overmuch importance is attached to the 

 conflicts, that in a large number of instances 

 they are mere "bickerings" and lead to nothing, 

 and that they are now only "formal," which 

 means, I suppose, that they are vestigial — 

 fragments of warfare that determined the survival 

 of the species in bygone ages. But if the 

 conclusion at which we have just arrived be 

 correct, if we can recognise a single aim passing 

 through the whole of the warfare — and that one 

 the removal of an intruder from a certain 

 position, then we need no longer concern our- 

 selves as to the degree of severity of the battles 

 — we see it all in true perspective. Neither 

 exhaustion nor physical inability are the sole 

 factors which determine the nature and extent of 

 the fighting; there is a more important factor 

 stiU — position. According, that is to say, to the 

 position which a bird occupies whilst fighting is 

 in progress, so its pugnacious nature gains or 

 loses susceptibility, and it is this gain or loss of 

 susceptibility which I refer to when I speak of 

 the fighting as being controlled. 



What we have then to consider is the relation 

 of "susceptibility" to "position." We can 

 explain the relationship in two ways. We can 

 say that the part of the nature of the male which 

 leads to the occupation of a territory, and is 

 partly hereditary and partly acquired, is stronger 

 than the part which leads the bird to fight, and 



