CHAPTER XXXII 



MUTUAL AID AND COMMUNAL 

 LIFE 



It is an altogether too common idea that in Nature all is 

 one fierce and unrelenting warfare for place and food and 

 life itself. While the "struggle to live" usually means to 

 the layman student of Nature an unrelieved competition 

 and often personal combat on the part of any one animal 

 species or individual, to the experienced naturalist it is a 

 large and general term which includes a great many kinds 

 of shifts for a living, some of which may depend on a total 

 cessation of individual competition and the adoption of 

 the principle of mutual aid. Many individuals of one 

 kind of animal may live together in a single elaborately or- 

 ganized community, as with the honeybee and the ants, 

 where each individual works for all in a measure never yet 

 realized among men. Or individuals of different species 

 of animals may live together in more or less developed con- 

 ditions of mutual tolerance and even helpfulness. Gre- 

 garious, commensal, social and communal forms of life 

 are all abundantly represented among the lower animals. 

 So that the phrase "struggle to live" must be imderstood 

 to include altruistic as well as competitive and warring 

 means. It must be understood to signify simply "means 

 to live." 



Commensalism. — Thd living together in peace and often 

 to mutual advantage of individuals of different kinds of 

 animals is called commensalism, or messmatism. 



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