Fauna of Polar Regions 



animal to be protectively coloured. If, it is 

 urged, those creatures that live in lands which 

 are covered in snow for half of the year have 

 become white in winter by the action of natural 

 selection in order to escape their foes, it is 

 obviously of paramount importance to all 

 creatures that they should be cryptically 

 coloured. Popular books on natural history 

 convey the impression that during winter the 

 snow-clad, ice-bound Arctic regions are peopled 

 by a fauna whose fur or hair rivals in whiteness 

 the snowy mantle of the earth. The impression 

 thus conveyed is misleading. It is true that an 

 unusually large percentage of the animals that 

 inhabit the polar regions are white in winter, but 

 the majority of the creatures which dwell there 

 do not assume the white garb of winter. 



As the fauna of the polar regions is a small 

 one, we are able to give lists of all the birds and 

 mammals which dwell in the Arctic and the 

 Antarctic regions. We have arranged these in 

 in three columns. In the first are placed those 

 creatures which are white throughout the year, in 

 the third those that retain their colour through 

 the winter, while the middle column contains 

 those forms which change their colouring with 

 the season. 



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