ANIMAL BEHAVIOR WALKER 299 



The female pronghorn antelope of western North America hides 

 her baby on the prairie or on ground with very little vegetation 

 by having it lie perfectly flat and still while she feeds or rests at 

 a distance. 



Musk oxen have adopted an excellent method of protecting their 

 young from the wolves and bears of the region that they inhabit. 

 They always go in small bands or herds, and when danger threat- 

 ens, the adults form a complete ring, facing outward, with the 

 young animals in the center of the ring. Thus, the charge of the 

 pack of wolves can be met from any direction. This manner of 

 defense was highly satisfactory for the preservation of the musk 

 oxen until the coming of man, with his guns. 



Most baby bats cling to the mother's nipple and to her fur while she 

 flits about through the air or hangs up to sleep or rest. On some 

 occasions, however, the mother leaves the little ones hanging in a 

 safe place, goes on her flight, then comes back to it. The so-called 

 naked bat {Gheiromeles) of Borneo carries her little one in a pocket 

 formed by a fold of skin between her back, sides, and wing. Most 

 bats have only one young at a time, although twins sometimes occur. 

 In the North American red bat {Nycteris) and hoary bat {Lasiurus) 

 there are occasionally triplets or quadruplets. 



In the colder parts of the Northern Hemisphere baby bears ( Ursiis, 

 Euarctos, and Thalarctos) are born while the mother is in hiberna- 

 tion, usually in February. New-born black bears weigh only about 

 a pound, and the mother does not leave them for even a moment 

 until springtime when she goes out to obtain food. 



In moving her baby from one nest to another a squirrel {Sciurus) 

 mother uses the following method. She turns the baby on its back 

 and grasps one of its legs or the skin of its under parts in her 

 teeth and lips, while the little one puts its forelegs around her neck 

 from one side and its hind legs and tail from the other. In this 

 way the baby is carried high enough so that its mother can use 

 her feet in climbing and leaping, while at the same time, the little 

 one helps to hold itself in place. 



A mother polar bear {Thalarctos) ^ when swimming, helps her 

 baby along by letting it cling with its mouth to her tail or long 

 hair. Thus she tows it along. When it is tired, she lets it ride on 

 her back. 



Gibbon {Hylohates and Symphalangus) babies cling beltlike 

 around their mother's body. This leaves the mother free to use 

 her arms and legs in swinging through the trees. 



In addition to feeding and protecting the young, the parents of 

 many kinds of mammals carefully lick their young ones to keep 

 them clean until they learn to wash and groom their own coats. 



