THE WEB OB BIBE 
91 
animals, developed their horns and their needles; the 
adder with the deadliest sting lived longer and laid more 
eggs than her stingless sisters; the giraffe with the longest 
neck could reach higher leaves upon the tree in time of 
drought or famine when his shorter-necked brothers were 
starving because the pasture had burned dry with the sun. 
Plants and animals and men must struggle against 
disease, against attacking animals, against climate. The 
polar bear protects himself from the cold by growing 
thick, heavy fur; the African’s skin is dark so that the 
sun cannot burn it. Man, seeing the warfare that goes on 
forever among the creatures beneath him, often tries 
to turn this struggle to his own advantage, sometimes 
with success, often with failure. To kill the tent-worm, 
he brought the English sparrow to America; in fifty 
years these birds became so numerous as to be more 
harmful than the tent-worm, and we should like very 
much to send them all fllying back to where they came 
from! When before our very eyes the robins steal 
the makings of a cherry pie from the top of our cherry 
tree, we are very angry, but nobody dares to kill off the 
whole race of robins and sparrows because we should 
then be tormented and our trees and crops destroyed by 
the millions of insects upon which these birds feed. If by 
some dreadful accident all the birds in the world should 
die, in six or ten years all of our trees, our grasses and 
7 
