3 02 AUTUMN AND WINTER 



swells the puffin's beak in the breeding-season vanishes 

 after the moult, together with the wattle-like protuberances 

 round the eye, and the rough red skin of the face. In all 

 their typical cases, the dress in spring and early summer is 

 more brilliant and elaborate than the winter plumage. In 

 many animals there is a similar, though less marked, fading 

 of summer hues as winter comes in. The winter coat of 

 deer, hares, polecats and martens, and several kinds of mice 



f«MME^ 



wim t er. 



and voles, loses the reddish or tawny hues of summer and 

 becomes a duller dun or grey. 



Many of the brightest colours and most elaborate orna- 

 ments of birds are special accompaniments of the nesting- 

 season, and disappear in the idle months of autumn and 

 winter. They are usually explained as being the results of 

 sexual selection, and as having been produced by perpetual 

 breeding from the stocks which most pleased the eyes of the 

 hen birds. In winter, when courtship loses its importance, 

 protective adaptation to some extent takes its place in con- 

 trolling the colours of birds' plumage and animals' pelts. 



In Britain we have no Polar bears or white snow-foxes 

 to help make up a really representative Arctic fauna ; but 

 the summits of some of the highest Scottish mountains still 



