500 



ELEMENTARY BIOLOGY 



516. Building. Of course other animals have built shelters, 

 and many species of birds build much neater nests than the 

 apes do, and much neater, probably, than primitive man built in 

 the tree tops. But man has finally succeeded in building shelters 



Fig. 261. Relics of man in the Stone Age 



/, hatchet ; 2, hammer-head ; s, ax ; 4,3, arrowheads ; 6, fishhooks. (/, 2, and 4, after 



Tyler ; s, j, and 6, original) 



so far beyond anything that other animals have made, that it 

 seems ridiculous to compare them. The point is, that although 

 the bees and the birds may build very good shelters, they build 

 the same, generation after generation, controlled in their actions 

 by comparatively fixed impulses or instincts ; whereas man has 

 no natural skill or plan for doing these things, yet can learn, 



