LUTHER BURBANK 
more than once referred were those that were the 
most highly specialized. 
But, on the other hand, a species that is able 
to change in such a way as to adapt itself to new 
conditions stands at least a chance of being pre- 
served, however widely the environment may be 
altered. And, in point of fact, most species in a 
state of nature have a considerable measure of 
adaptability. Individual variation is the universal 
rule, and such variations are accentuated by nat- 
ural selection very much as the plant developer 
accentuates them by artificial selection. So the 
plants and animals in a state of nature are plastic 
material, and under changing conditions of en- 
vironment which represent probably the usual and 
normal condition of things, they are constantly, 
even if slowly, being modified. And of course 
such modifications, when they have been suffi- 
ciently added to, alter the character of the species 
altogether. 
Which is only a detailed and roundabout way 
of saying that species are evolved and transformed 
into new species under the influence of natural 
selection. 
But whoever considers this matter attentively 
will come presently to realize that in any such 
analysis of the operation of natural selection in 
the evolution of species as that just suggested, 
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