240 CHILDHOOD OF ANIMALS 



roots, to strip fruit or leaves from trees require a certain amount 

 of skill, and it is amusing \ o see how clumsily young animals usually 

 set about these necessary tasks. When the food is a living prey 

 that runs or jumps or turns on its enemy, even greater knowledge, 

 skill and agility are required. The young animals have to learn 

 to defend themselves by recognising danger, by hiding or escaping 

 by swiftness, or by fighting. 



Young birds and mammals differ very much in the difficulty 

 they seem to have in acquiring their various forms of locomotion. 

 Ducklings, even if they have been reared under a hen, take to the 

 water at once and swim without any practice. Cygnets have to 

 be coaxed or pushed into the water by their parents, and seem 

 anxious to get out of it, either on the bank or by climbing 

 on the backs of the adults (see Plate XI). Young gulls 

 avoid the water for a considerable time, but eventually are 

 taken to it by their parents. The aquatic mammals, except, 

 of course, whales, dolphins and porpoises, manatees and 

 dugongs, are all born on land, and have to be coaxed or driven 

 into the water by their parents, but as soon as they get there 

 swim as instinctively as fishes or snakes. So far as I know, 

 all the quadrupeds are able to swim, partly because the attitude 

 in the water and the movements of the limbs are not very different 

 from those to which they are accustomed. Most of them are very 

 much alarmed at first and would readily drown from the exhaustion 

 produced by their violent, spasmodic efforts. The fact, however, 

 that most of them soon become accustomed to water, and swim with 

 ease for long distances, shows the remarkable difference between 

 their flexible varied possibilities and the rigid adaptation of lower 

 animals. 



The ancestors of birds were quadrupeds and no doubt walked 

 on all fours like most living lizards. The front limbs have been 

 transformed into wings, and birds are now purely bipeds, walking, 

 hopping or running only on their hind-legs. This form of loco- 

 motion appears to be more difficult to learn than the quadrupedal 

 gait of four-legged creatures. Newly hatched chicks take some 

 hours to learn to walk, even if they are helped by the mother. At 

 first they shuffle along clumsily, using the wings as crutches. The 

 wing of a nestling chick has a little claw at the tip of the thumb, 

 and if a still earlier stage be examined, the tips of the first and 

 second fingers as well as the thumb are seen to be separate, and 

 appear as if they were going to develop claws, although they do 



