22 EVOLUTION MADE PLAIN 
By his great discovery Darwin delivered the 
heaviest solar plexus blow to human vanity it 
ever received. For this he deserves, and re¬ 
ceives, the eternal gratitude of every right- 
thinking man and woman. 
How was evolution brought about? What 
are its laws, and how do they work? 
NATURAL SELECTION 
When the farmer or the stock-breeder selects 
his seeds or his animals for propagating pur¬ 
poses he has an eye to a great natural law, 
heredity. He knows that scrub animals and 
the seeds of degenerate plants will stamp their 
inferiority upon their descendants. He has 
learned that like produces like, therefore he 
selects such seeds and animals as will produce 
those best suited to his purposes. He is not 
only guided by his knowledge of a great law 
of Nature, but in the main he is following her 
method in preserving and improving the breed. 
This method of changing and improving plants 
and animals under domestication is called ar¬ 
tificial selection. 
Plants and animals in the natural state are 
capable of multiplying at so enormous a rate 
that there is an incessant struggle for exist¬ 
ence going on among them. If it were not for 
this fierce struggle with one another and with 
their enemies and other environmental forces 
in which the vast majority die early, the world 
would be overstocked. There is hardly a spe¬ 
cies of animal of which a single pair would not 
choke out all other animal life in a few genera- 
