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A difficulty, diametrically opposite to this which we have just been considering, has been advanced, namely, 1861 1866
OMIT 1869 1872

could 1861 1866
it has been asked, could 1869 1872

advancement or in the differentiation and specialisation 1861 1866
the advancement or differentiation 1869 1872

1 blocks not present in 1859 1860 1866 1869 1872; present in 1861
I can make no sufficient answer; and can only say that as we have no facts to guide us, all speculation on the subject would be baseless and useless.

would come into action, namely, 1866
OMIT 1869 1872

different." 1866
different" would come into action. 1869 1872

through their preservation, either 1866
through their preservation either 1861
thus 1869 1872

as I remarked 1866 1869 1872
I must recur to what was stated 1861

OMIT 1866 1869 1872
where I say that 1861

due allowance be made 1861 1866
we make due allowance 1869 1872

to act on and accumulate. In no case, probably, has time sufficed for the utmost possible amount of development. In some few cases there
has
may have
been what we must call retrogression of organisation. But the main cause lies in the
fact
circumstance
that under very simple conditions of life a high organisation would be of no service,— possibly would be of actual disservice, as being of a more delicate nature, and more liable to be put out of order and
thus
thus
injured.
A difficulty, diametrically opposite to this which we have just been considering, has been advanced, namely,
looking
Looking
that, looking
to the
first dawn
dawn
of life, when all organic beings, as we may
believe,
imagine,
presented the simplest structure,
how,
how
could the first steps in advancement or in the differentiation and specialisation of parts have arisen? Mr. Herbert Spencer would probably answer
that,
that
as soon as
the most
the most
simple unicellular organism came by growth or division to be compounded of several cells, or became attached to any supporting surface, his law would come into action, namely, "that homologous units of any order become differentiated in proportion as their relations to incident forces become different." But as we have no facts to guide us,
all
all
speculation on the subject is
almost useless.
useless.
It is, however, an error to suppose that there would be no struggle for existence, and, consequently, no natural selection, until many forms had been produced: variations in a single species inhabiting an isolated station might be beneficial,
and
and,
through their preservation, either the whole mass of individuals might
be
become
modified, or two distinct forms might arise.
But
But,
as I remarked towards the close of the Introduction, OMIT no one ought to feel surprise at much remaining as yet unexplained on the origin of species, if due allowance be made