→ though ranked as distinct species, being closely related, 1859 1860 1861 1866 |
being closely related, though ranked as distinct species, 1869 1872 |
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→ two 1859 1860 1861 |
in any two 1866 1869 1872 |
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→
Forms
.—
1859 1860 |
compared with Living Forms.
—
1861 |
compared with Living Forms. 1866 |
compared with Living Forms.
1869 |
compared with Living Forms
. 1872 |
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↑ 2 blocks not present in 1859 1860; present in 1861 1866 1869 1872 |
We have seen in the fourth chapter that the degree of differentiation and specialisation of the parts in
all
organic beings, when arrived at
maturity, is the best standard, as yet suggested, of their degree of perfection or highness.
We have also seen that,
as the specialisation of parts and organs
is an advantage to each being, so natural selection will tend
to render the organisation of each being more specialised and perfect, and in this sense higher; not but that it may and will
leave many creatures with simple and unimproved structures fitted for simple conditions of life, and in some cases will even degrade or simplify the organisation, yet leaving such degraded beings better fitted for their new walks of life.
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↑ 1 blocks not present in 1859 1860 1861 1866 1869 1872; present in |
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→ sense the more recent forms must, on my theory, be higher than the more ancient; for each 1860 |
manner, 1866 |
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vicissitudes of climate during the pleistocene period, which includes the whole glacial
and note how little the specific forms of the inhabitants of the sea have been affected. |
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On the theory of descent, the full meaning of the
fossil remains from closely consecutive
→though ranked as distinct species, being closely related,
is obvious. As the accumulation of each formation has often been interrupted, and as long blank intervals have intervened between successive formations, we ought not to expect to find, as I attempted to show in the last chapter, in any one or
→two
all the intermediate varieties between the species which appeared at the commencement and close of these
but we ought to find after intervals, very long as measured by years, but only moderately long as measured geologically, closely allied forms, or, as they have been called by some authors, representative species; and these
do find. We find, in short, such evidence of the slow and scarcely sensible
of specific forms, as we have
right to
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→
Forms
.—
↑ There has been much discussion whether recent forms are more highly developed than ancient. I will not here enter on this subject, for naturalists have not as yet defined to each other's satisfaction what is meant by high and low forms. ↑ In
more general
→sense the more recent forms must, on my theory, be higher than the more ancient; for each
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