THE LAW OF PROGRESS 
methods; therefore, while each individual 
may be breeding toward the same stand- 
ard of perfection, yet each one of them 
may be trying to perfect his birds by 
different methods; to cross two strains of 
the same breed that had been bred by 
different methods, and by different men, 
towards the same standard of perfection, 
seldom, if ever, produces good results. In 
nature this danger would not exist, for 
she is breeding all of her families, of the 
same variety and species, in the same 
direction; so that if infusion of blood 
takes place, in nature, between distant 
related families, no perceptible change 
between the offspring and the parents 
takes place, for the reason that both 
families have been bred towards the same 
common standard, by the same methods. 
This rule will not hold good if the two 
families are so far separated that they 
are living under different environment, 
for nature will seek to fit each family for 
the environment that surrounds them; 
and if these families have been widely 
separated, and have lived under different 
environment for a long time, they will be 
so much changed that to cross the two 
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