96 CHILDHOOD OF ANIMALS 



certain amount of counter-shading being the chief variation in the 

 general clothing of dark grey or brownish fur, but a few like the 

 spotted dasyures and the striped Tasmanian wolf have special 

 patterns. The sexes are always alike, and the young, which are 

 born as naked and quite immature embryos, acquire the pattern of 

 the parents as soon as they become clothed with fur. 



If we consider the patterns of mammals as a whole, it is plain that 

 the simplest and most primitive types consisted of spots, and 

 that these were the expression of the tessellated or particulate 

 character of the skin. In the natural course of growth these spots 

 may expand into short stripes, or they may fuse to form bands 

 running hoop wise across the body, or along its length. If there is 

 a pattern of this kind in the adult, it is always present in the young. 

 Undoubtedly it must often aid in making the young animals or 

 the adults invisible as they lie in the dappled shadow of leaves, 

 but the pattern occurs so often, in so many different kinds of animals, 

 living under so different conditions, that although it may have been 

 retained because it was useful, it does not seem probable that its 

 usefulness is the direct cause of its origin. Very often the primitive 

 spots or stripes are replaced in the adult by an even tone, marked 

 only by counter-shading, and sometimes this monotonous tint 

 appears even in the first coats of the young. The fact that it so 

 often replaces a primitive livery of spots would seem to show 

 that it is of later origin, a more highly developed kind of pattern. 

 Lastly, it very frequently happens that instead of a monotonous 

 shade, the body is marked by vivid patches of light and shade, or 

 of colour, over regions that do not seem to correspond with structural 

 differences of the body. These showy, conspicuous patterns are 

 often ruptive, and may serve for concealment by breaking up the 

 natural outlines of the animals. When they are present, they are 

 generally more strongly marked in the males than in the females, 

 and they replace either the monotonous or spotted or striped 

 pattern of the young. 



The changes from juvenile to adult patterns are frequently 

 abrupt and are associated with the natural autumn or spring 

 moult. When the young animals become nearly full grown in one 

 season, they appear first in the rough and plainer winter pelage ; 

 when their youth lasts longer, it is not until the moult after the first 

 winter that they assume the pattern of the adult. 



