154 BEHAVIOR OF PIGEONS. 



RECOGNITION OF INDIVIDUALS. 



Old birds distinguish their own young from other young and from adults in wild species, 

 where marking, color, size, etc., are so nearly alike that we can not distinguish individuals. 

 Birds are able to distinguish their own mates instantly. I think, too, that the parents 

 remember and recognize their young, but not as offspring. They have no more interest 

 in them than they have in any other bird. They seem to know them; they remember 

 things of that sort. They remember individual birds. Every bird in a flock remembers 

 every other bird, but I do not think they know any particular birds as their own offspring. 



A young Geopelia humeralis, 7 weeks old, had been separated from its mate soon after 

 hatching and placed under the care of ring-doves. Later I brought the two together. The 

 one that had been under the care of ring-doves was terrified at the sight of his own mate, 

 raised his wings, and bristled up for defense. This was toward night. I left the two 

 together in a pen by themselves. The next morning, the two still kept apart, or rather 

 the one brought up under its parents seemed not to have much fear of the other, but 

 the latter continued to have equally great fear. This shows two things : the one brought 

 up under its parents, familiar with its own species, saw no cause for alarm in its mate; 

 but the latter, familiar with ring-doves, recognized its own mate the same species 

 as a "stranger" and as an "enemy." These two birds finally got acquainted, when kept 

 by themselves in the same cage, and now after 4 days together they roost together, side 

 by side. 



Two pairs of young common pigeons, each pair about 4 weeks old, were reared in nest- 

 boxes on the floor of two adjoining pens in my library; they were reared within 3 to 6 

 inches of each other, being separated only by a coarse wire netting. Here these two pairs 

 could see each other plainly and were therefore not strangers by sight. To-day I put both 

 pairs together, removing the old birds from the pen in which they were placed. 



They did not at first appear quarrelsome at all, and I supposed they were to get on 

 kindly together. But when night came one pair got into a nest-box about 8 feet above the 

 floor and refused to allow the other parr to sit with them. The pair that were masters 

 were very cordial to each other, fondling each others' head, etc., and never making the 

 mistake of attacking each other while battling off the others a mistake easy to make 

 when four doves are contending for a place less than a foot square. One pair was driven 

 out and, when I put them back, they were hustled out more quickly than before. I then 

 gave them a perch below the box, and here they sat close beside each other, while the 

 victors sat above them. The next night the victors took the place they had won and 

 the conquered took the lower seat. The matter was settled; each knew its place. The 

 mates of each pair were fond of each other, but the two pairs did not like each other. 



Sitting side by side in the same box, the mates had evidently acquired a filial affection 

 for each other, and they felt differently towards the other pair and always kept up the 

 distinction. Here is recognition of partners, love; recognition of non-partners, aversion; 

 the union of the pair owning the roost against the newcomers; and submission to the 

 results of victory as final on the part of the conquered. Is that not human? Is such 

 behavior conceivable without some intelligence? 



That ring-doves remember and recognize each other after a period of separation was 

 illustrated in the case of the two females of "pair D". 1 I separated these females, giving 

 the larger one as a mate to a white-ring male and putting the other in a cage alone and 

 out of the sight of the first. Nine days after the separation I brought the caged female 

 back to her sister, who was sitting quietly on her eggs. As soon as the dove from the cage 

 saw the sister on the nest she at once gave a laugh of joy and recognition. She flew to the 

 nest, but was repelled by her sister, who was taken by surprise. But after a moment 



1 The complete record is given in Chapter III, under the heading "The Pairing of Two Females." EDITOR. 



