CHAPTER V 



SOCIAL LIFE OF ANIMALS 



1. Partnerships 2. Co-operation and division of labour 3. Gre- 

 garious life and combined action 4. Beavers 5. Bees 6. 

 Ants 7. Termites 8. Evolution of social life 9. Advan- 

 tages of social life 10. A note on " the social organism ' -11. 

 Conclusions. 



THE over-fed plant bears many leaves but its flowers 

 are few ; the artificially over-exercised rat has the normal 

 weight-proportions of its organs greatly altered. It 

 seems as if organ competed with organ within the 

 body, as if one tissue might outgrow another in the living 

 web, as if there were some struggle for existence between 

 the individual units which form the city of cells in any 

 of the higher animals. This idea of internal competition 

 has been elaborated by a German biologist, Roux, in a 

 work entitled The Struggle oj Parts within the Organism, 

 and it is full of suggestiveness. Yet we rightly think 

 of an organism as a unity in which the parts are bound 

 together in mutual helpfulness, being members one of 

 another. 



Now, just as a biologist would exaggerate greatly if he 

 maintained that the struggle of parts was the most im- 

 portant fact about an organism, so would a naturalist if 

 he maintained that there was in nature struggle only 

 and no helpfulness. 



Coherence and harmony and mutual helpfulness of 

 parts whether these be organs, tissues, or cells are 

 certainly facts in the life of individuals ; we have now 

 to ask how far the same is true of the larger life in which 

 the many are considered as one. 



1. Partnerships. Animals often live together in strange 



72 



