ZOOGENESIS 



theless it is a fact that the closest parallel to the 

 activities of man is to be found in the activities of the 

 insects and their allies and not among the vertebrates 

 or backboned animals. And furthermore, among the 

 vertebrates the birds as a w^hole come rather nearer to 

 man in the scope of their activities than do the other 

 mammals, while among the mammals the rodents — 

 rats, mice, squirrels, beavers and their relatives — are 

 the most similar. 



The use of fire and of fashioned tools is confined to 

 man. Certain ants and other insects, some reptiles, 

 as the crocodiles and alligators, and certain of those 

 strange birds called brush-turkeys or megapodes (Meg- 

 apodida^) make use of artificial heat of bacterial origin 

 derived from decaying vegetation consciously and 

 knowingly gathered and assembled for that purpose. 

 But the ignition point is never reached. 



Certain digger wasps use little pebbles or little bits 

 of stick held in the jaws to smooth down the earth 

 over a buried victim. The spinning ants of the Old 

 World tropics build their silk nests by using their 

 own grubs which they hold in their jaws and pass 

 back and forth from leaf to leaf. The grubs have silk 

 glands which the adults lack, so that the construction 

 of silken nests by ants is only possible through a curi- 

 ous system of enforced child labor. There are various 

 other cases of the use of tools and implements by 

 insects. But the tools they use are never made 

 by them. 



Very many insects in their early stages clothe them- 

 selves. They encase their bodies in a little jacket 



[7] 



