The Scope of Natural Selection. 
3y J. LIONEL TAYLER. 
A RECONSIDERATION of a few of the chief objections which have from 
time to time been urged against the theory of natural selection may, 
in view of the more recent development of its principles, be not 
without some value at a time when test cases to decide the question 
of use-inheritance and the power of natural selection are being 
continually brought forward. 
In this paper I shall throughout follow Lloyd Morgan, Mark 
Baldwin, and others in the precise usage of the terms, variation, 
modification, adaptation, and accommodation. 
Variation will apply to changes which are of germinal origin. 
Modification will apply to changes which are impressed on the 
“body ” or soma in the course of individual life. 
Adaptation will apply to those changes which have been produced 
by the selection of favourable variations. 
Accommodation will apply to those alterations which have been 
produced by the reaction of the soma to environmental 
conditions. 
We may seek to interpret the facts of organic evolution by 
resting wholly or in part upon one, or a combination of more than 
one, of the following assumptions :— 
1. That organisms have evolved along definite lines, wholly or 
chiefly dependent upon the nature of each organism, developing either 
completely or partially irrespective of the peculiarities of the environ- 
ment. On this view the more or less unsuitable organisms are simply 
eliminated, but this elimination is of little or no importance in 
development, the assumption being that every organism that is not 
exterminated evolves at its own rate, and that its development is 
neither retarded nor accelerated by the presence or absence of other 
organisms. 
2. That organisms are modifiable by environment and _ that 
modifications so produced are inherited, the hereditary relation being 
subservient to the action of the environment. This assumption has 
to be considered under two heads. 
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