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differences may be developed in connection with the sub
division of labour which occurs in connection with neuter
insects. And inasmuch as different food and treatment
result in the different issues of female and neuter insects,
so it is not unreasonable to suppose that it may be with
different kinds of neuters. The marvel of the whole
theory is not lessened by such explanations, but they
serve to establish an analogy between these and the more
familiar phenomena of insect life.
For the reasons which have just been assigned, I do
not believe that instincts can have arisen or been modified
by the action of Natural Selection in the case of those
animals which are endowed with intelligence. Let us
once more note what Mr. Romanes says upon this subject,
quoting him a little more fully than heretofore.
“ If we accept the theory of Natural Selection as of any validity at
all in explaining the evolution of structures, it becomes simply
impossible to dispute that it must also be of some validity in explain
ing the evolution of instincts. For instincts, no less than structures,
are of use to the animals possessing them ; like structures, they vary
and are inherited ; like structures, therefore, and no less than
structures, they are amenable to all those influences which are
comprised in the term, ‘ survival of the fittest.’ And when, in
addition to this, we find abundant proof of the intelligence of
animals guiding the course of variation—so that, unlike the case
of structures, instincts do not recpjire to wait for Natural Selection to
seize upon fortuitous variations, but themselves supply variations
which in relation to any change of environment are from the first
adaptive—when we find this, we cannot fail to perceive that in no
department of organic nature is Natural Selection operating at so
much advantage. Lastly, when over and above all this we find
abundant evidence of the principle of ‘lapsing intelligence’ co
operating with that of Natural Selection, we must upon the whole
conclude that, if the theory of evolution is of any validity in any
case as a scientific interpretation of natural phenomena, nowhere is
it more successful in this respect than it is in the domain of instinct.”
—(.Fortnightly Review, vol. xxxviii., fip. 9J-4-)
It should be observed that Mr. Romanes starts with
the assertion that the influence of Natural Selection in