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REV. J. T. GULICK ON DIVERGENT EVOLUTION 
In the case of Natural Selection, the separation it introduces 
is between the living and the dead, between the successful and the 
unsuccessful. In other words, Natural Selection is the exclusion 
of all the forms that through lack of adaptation to the environ- 
ment fail of leaving progeny, and therefore in the exclusive 
generation of the forms that through better adaptation to the 
environment are better able to propagate. Variation with the 
Natural Selection of other than average forms may therefore ac- 
count for the transformation of an ancient species into a series of 
successive species the last of which may now exist in full force ; 
hut without the aid of Segeneration it will hy no means account 
for the divergent evolution of any one of these species into a family 
of coexisting species. 
As I have just shown, Natural Selection is the exclusive genera- 
tion of those better fitted to the environment ; and it tends to 
the modification of species simply through the generation of the 
better fitted forms, while they are prevented from crossing with 
the less fitted, which fail of propagating through their lack of 
fitness. Now from the very nature of this process, which results 
from the success and failure of individuals in appropriating the 
resources of the environment, it follows that it cannot be the 
cause of separation between the successful competitors, and there- 
fore any divergence of character that arises between the different 
groups of the successful cannot be attributed to Natural Selec- 
tion. Natural Selection explains the prevention of crossing 
between the fitted and the unfitted, and shows how the succes- 
sive generations of a species may gradually depart from the 
original type, becoming in time a different species ; but it can- 
not explain the divergences that arise between those that have, 
hy the fact of successful propagation , proved their ftness. It 
depends on superiority of adaptation to the environment, and 
tends to produce increasing adaptation ; but divergent kinds of 
adaptation are not necessary conditions for it, and it cannot he 
the cause of increasing divergence between the incipient kinds that 
otherwise arise. 
Divergent Evolution not explained by “ the advantage 
of divergence of characteb.” 
Two sections of the 4th chapter of the ‘ Origin of Species ’ 
are given to the discussion of the “ principle of benefit being 
derived from divergence of character,” which it is maintained 
