e Maeritherium,
in the middle Tetrabelodon (After Lancaster); below African elephants
(After Gambier Bolton).]
Owing then to this property of the germ plasm to duplicate itself in a
large number of samples not only is an opportunity furnished to an
advantageous variation to become extensively multiplied, but the presence
of a large number of individuals of a given sort prejudices the probable
future result.
The question may be raised as to whether it is desirable to call selection
a _creative_ process. There are so many supernatural and mystical
implications that hang around the term creative that one can not be too
careful in stating in what sense the term is to be used. If by creative is
meant that something is made out of nothing, then of course there is no
need for the scientist to try to answer such a question. But if by a
creative process is meant that something is made out of something else,
then there are two alternatives to be reckoned with.
First, if it were true that selection of an individual of a certain kind
determines that new variations in the same direction occur as a consequence
of the selection, then selection would certainly be creative. How this
could occur might be quite unintelligible, but of course it might be
claimed that the point is not whether we can explain how creation takes
place, but whether we can get verifiable evidence that such a kind of thing
happens. This possibility is disposed of by the fact that there is no
evidence that selection determines the direction in which variation occurs.
Second, if you mean by a creative process that by picking out a certain
kind of individual and multiplying its numbers a better chance is furnished
that a certain end result will be obtained, such a process may be said to
be creative. This is, I think, the proper use of the term creative in a
mechanistic sense.
CONCLUSIONS
In reviewing the evidence relating to selection I have tried to handle the
problem as objectively as I could.
The evidence shows clearly that the characters of wild animals and plants,
as well as those of domesticated races, are inherited both in the wild and
in the domesticated forms according to Mendel's Law.
The causes of the mutations that give rise to new characters we do not
know, although we have no reason for supposing that they are due to other
than natural processes.
Evolution has taken place by the incorporation into the race of those
mutations that are
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