ECOLOGICAL m 



contemporary evolution was studied so brilliantly by the lamented 

 Prof. Kammerer, but dense crowding is not in itself social. No 

 evolutionist expects to find hard-and-fast lines, and we are far from 

 asserting that birds are the first Vertebrates to sound the social 

 note. We simply wish to make it clear that the occurrence of, say, 

 shoals of mackerel, whiting, sprats, or herring does not illustrate 

 sociality. Yet we are interested when a recognised ichthyological 

 authority. Dr. Harry M. Kyle, says in his Biology of Fishes (1926) 

 that the smaller kinds sometimes combine to attack the larger. 

 For that sounds, however feebly, the social note. "The salmon is 



Fig. 30. 



A Wasp's Nest, From a specimen. The structure is made of chewed wood, 

 which may be compared to paper. One storey is fastened to another, 

 and each bears down-turned cells in which the eggs develop into grubs. 

 The series of combs is surrounded by windproof and waterproof 

 envelopes. 



one of the most powerful fishes in fresh water, yet the much smaller 

 eels have been known to work together to devour it, even in the 

 pride of its strength before spawning." Perhaps it is just as well 

 that there are not more than adumbrations of social combination 

 among the low-brained reptiles, amphibians, and fishes. Vain man 

 would not like to hear of the Honourable Company of Cobras or 

 the Union of Operative Sharks ! 



3. Among Backboneless Animals there is notable sociality in 

 almost all the ants, in all the termites, in 500 out of 10,000 species of 

 bees, in many of the wasps, and in a considerable number of beetles. 

 Of crowded gregarious life without corporate action there are many 

 examples, as in shoals of "sea-butterflies" (open-sea molluscs), 

 great companies of free-swimming crustaceans and sedentary acorn- 



