i84 THE BIOLOGY OF BIRDS 



is, guided by impulse, unanalysable fancies, individual 

 predilection." 



§ 5. The Observations of Selous 



Of great interest, and, as it seems to us, of great import- 

 ance are the numerous observations recorded by Edmund 

 Selous, which certainly corroborate Darwin's view that the 

 female plays a real part in selection. We wish to give 

 some characteristic illustrations chosen from the abundant 

 first-hand data which this distinguished naturalist has 

 collected. 



In mallards there is apparently affectionate companion- 

 ship not directly associated with sexual satisfaction. " Instead 

 of separating, they continue to swim side by side in the most 

 affectionate manner, and whichever of the two may take the 

 initiative in going anywhere is closely followed by the other. 

 This continues hour after hour, right through the morning, 

 deep into the afternoon — for the whole day, there can be no 

 doubt, were one to set it out, and so for day after day. More- 

 over, the intervals between the performance of the nuptial 

 rite are considerable — several hours, it would seem. En- 

 visaging these facts, and observing the whole manner of the 

 two birds, to me it seems evident that friendship and 

 affection, irrespective of sexual appetite, keep such pairs 

 together. Their married relations are, in fact, very like our 

 own, at their best, and if it be said that we cannot argue from 

 ourselves to other animals, it is certainly less scientific to 

 assume a difference in kind, in spite both of appearances and 

 the known facts of evolution." Where Mr. Selous is 

 perhaps mistaken is in the interpolation " irrespective of 

 sexual appetite." The safer position is that alongside of the 

 sexual appetite there are psychical linkages analogous to 

 affection. 



It may be that the dawning sense of property and pre- 

 serves may find expression in the way one pair of oyster- 

 catchers will hunt another pair, all four piping, or a pair 

 will unite to drive off a bold intruder (Selous, 1906). But 



