BIOLOGY 



saw them they ran up to them joyfully, saying: " Here's 

 pa and ma, hooray!" To their surprise they got the 

 reverse of a cordial welcome, being driven away with 

 vicious peckings. They were driven on to the larger 

 colony and were swallowed up in it. 



The Adelies are not demonstrative of their affections. 

 It is difficult to discover if they have any beyond the 

 instinctive affection for the young. The pairing appears 

 to be a purely business matter, and the mates don't even 

 show any power to recognise one another. A penguin 

 was injured by the dogs, but it seemed possible that it 

 might recover, so we did not at once put it out of pain. 

 In a couple of days it died. Shortly after we noticed a 

 live penguin standing by it. We removed the dead bird 

 to a distance, and after a while found the other standing 

 beside it as before. It was the general opinion that it 

 was the dead bird's mate which had found it out. Such 

 an action is entirely opposed to what we expect after a 

 long study of their habits. There are always plenty of 

 dead birds about a rookery, and the living go about 

 entirely indifferent to them. It is puzzling in any point 

 of view, but it is less difficult to believe that the bird found 

 its dead mate than that it took an interest in a dead 

 stranger. 



Altruism 



When the young birds are well grown if there is an 

 alarm they flock together, and any old birds present in 

 the colony form a wall of defence between the young 

 and the enemy. This habit has given rise to the belief 

 that they are somewhat communistic in their social order, 

 and that the defence of the colony is a concerted action. 

 It is not so. Each bird is defending its own young one 

 only, and will often fight with another of the defending 



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