x THE WILL IN DEVELOPMENT 171 



tions of function tending to racial preservation would have 

 an even better chance of survival than variations tending 

 only to the preservation of the individual. Accordingly, 

 from an early stage indeed in a sense from the very 

 lowest heredity builds up structures, which in response, 

 partly, perhaps, to internal changes, partly to definite out- 

 ward stimuli, lead the individual to mate, to produce and 

 perhaps make elementary provision for the young, and 

 finally to consort in many cases with others of its kind. 

 These instincts, on close examination, reveal the character- 

 istic limitations, defects and individual variations of struc- 

 tures that have been roughly shaped to their work by the 

 indirect action of heredity. Thus, the infant mammal has 

 an instinctive impulse which is satisfied by the sucking of 

 the breast, but does not unfailingly and unaided lead it 

 to find the breast. It follows its mother, but its initial 

 impulse is often to follow any large slowly moving object. 

 A sparrow will feed the cuckoo that has expelled her own 

 young, because she cannot resist the sight of a callow nest- 

 ling and a bill gaping for worms. The fabric of instinct 

 as a series of responses to stimulus is well seen in the cries, 

 clucks, whistles that stir the mating instincts, warn the 

 young or gather them around the mother to share the food. 

 Every gregarious species depends largely on sounds of this 

 kind, to which the response is highly uniform. But social 

 life in the purely instinctive stage remains necessarily in a 

 rudimentary condition. The hereditary apparatus of itself 

 can do no more than provide certain typical forms of 

 operation, and can neither advance to true parental care for 

 the individual young nor from mere gregariousness l to 

 genuine co-operation. In fact, behaviour testifying to 

 regard for another as an individual is, I believe, confined 

 to the types mammalia, birds, and possibly the highest 

 insects among which there is independent evidence of 

 intelligence at the level of that which has been described 

 as the direct correlation of articulate experience. 



1 Gregariousness proper is the mere tendency to consort, a tendency 

 which has certain obvious advantages, e.g. warmth, the improved chance 

 of sharing any find made by one individual, and, indirectly it may be, 

 defence. 



