128 SECRETS OF ANIMAL LIFE 



which were here a few months ago are asleep, or 

 have gone on a journey, or have, as individuals, 

 ceased to be. 



The wintry aspect of the realm of organisms must 

 be considered from within and from without, for 

 life is rhythmic and is punctuated by the seasons. 

 On the one hand, there is a deep reason why high- 

 level activity cannot be for long continuous, why 

 it must be interrupted by periods of rest. It is 

 not merely that the living engine has to be stoked; 

 it is that the framework requires opportunity to 

 keep passably young. It is continuity that kills. 

 For many creatures winter is the time when processes 

 of rejuvenescence get a chance to counteract the 

 encroachments of senescence. How useful, often, 

 for the overworked brain is it to sleep the round of 

 the clock. The hibernal slumbers of hedgehog and 

 dormouse, of marmot and bat, the winter coma of 

 tortoise and slow-worm, the lethargic condition of 

 frogs and snails, are no doubt adaptive reactions to 

 severe external conditions, subtle organic illustra- 

 tions of Brer Rabbit's policy of "lying low and 

 saying nuffin"; but our point is that the quiescence 

 of winter has in some cases a more internal aspect, 

 it is the inevitable pause in a strenuous life. Quite 

 extraordinary in some humble, but intensely active, 

 animals (Bryozoa, for instance) is the way in which 

 the framework can be periodically taken to pieces 

 and built up again. One suspects that organic 

 immortality is commoner than is usually supposed. 

 And the recuperation has obviously a prospective 



