Comparison with 1861 |
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each other, which again implies extinction. The genera Ornithorhynchus and Lepidosiren, for example, would not have been less aberrant had each been represented by a dozen species
instead of by
a single one;
but such richness in species, as I find after some investigation, does not commonly fall to the lot of aberrant genera.
We can, I think, account for this fact only by looking at aberrant forms
as failing groups
conquered by more successful competitors, with a few members preserved by some unusual coincidence of favourable circumstances.
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Mr. Waterhouse has remarked that, when a member belonging to one group of animals exhibits an affinity to a quite distinct group, this affinity in most cases is general and not special: thus, according to Mr. Waterhouse, of all Rodents, the bizcacha is most nearly related to Marsupials; but in the points in which it approaches this order, its relations are general, and not to any one marsupial species more than to another. As the
points of affinity of the bizcacha to Marsupials
are believed to be real and not merely adaptive, they are due on my theory
to inheritance in common. Therefore we must suppose either that all Rodents, including the
biz- cacha, biz- cacha, 1861 | bizcacha, 1859 1860 1866 1869 1872 |
branched off from some
very very 1859 1860 1861 | very 1866 1869 1872 |
ancient Marsupial, which will
have had a character in some degree intermediate have had a character in some degree intermediate 1859 1860 1861 |
naturally have been more or less intermediate in character 1866 1869 1872 |
with respect to all existing Marsupials; or that both Rodents and Marsupials branched off from a common progenitor, and that both groups have since undergone much modification in divergent directions. On either view we may
suppose that the bizcacha has retained, by inheritance, more of the character
of its ancient progenitor than have other Rodents; and therefore it will not be specially related to any one existing Marsupial, but indirectly to all or nearly all Marsupials, from having partially retained the character of their common progenitor, or of an
early member of
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each other, which again implies extinction. The genera Ornithorhynchus and Lepidosiren, for example, would not have been less aberrant had each been represented by a dozen
species species 1859 1860 1861 1866 1869 | species, 1872 |
instead of
by by 1859 1860 1861 1866 1869 |
as at present by 1872 |
a single
one; one; 1859 1860 1861 1866 | one, 1869 1872 |
but such richness in species, as I find after some investigation, does not commonly fall to the lot of aberrant genera. but such richness in species, as I find after some investigation, does not commonly fall to the lot of aberrant genera. 1859 1860 1861 1866 |
or by one or two. 1869 |
or by two or three. 1872 |
We can, I think, account for this fact only by looking at aberrant
forms forms 1859 1860 1861 1866 | groups 1869 1872 |
as
failing groups failing groups 1859 1860 1861 1866 |
forms which have been 1869 1872 |
conquered by more successful competitors, with a few members
preserved by some unusual coincidence of favourable circumstances. preserved by some unusual coincidence of favourable circumstances. 1859 1860 1861 1866 |
still preserved under unusually favourable conditions. 1869 1872 |
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|
Mr. Waterhouse has remarked that, when a member belonging to one group of animals exhibits an affinity to a quite distinct group, this affinity in most cases is general and not special: thus, according to Mr. Waterhouse, of all Rodents, the bizcacha is most nearly related to Marsupials; but in the points in which it approaches this order, its relations are general, and not to any one marsupial species more than to another. As
the the 1859 1860 1861 1866 1869 | these 1872 |
points of affinity
of the bizcacha to Marsupials of the bizcacha to Marsupials 1859 1860 1861 1866 |
OMIT 1869 1872 |
are believed to be real and not merely adaptive, they
are due on my theory are due on my theory 1859 1860 1861 1866 |
must be due in accordance with our view 1869 1872 |
to inheritance
in common. in common. 1859 1860 1861 1866 |
from a common progenitor. 1869 1872 |
Therefore we must suppose either that all Rodents, including the
bizcacha, bizcacha, 1859 1860 1866 1869 1872 | biz- cacha, 1861 |
branched off from some
....... 1866 1869 1872 | very 1859 1860 1861 |
ancient Marsupial, which will
naturally have been more or less intermediate in character naturally have been more or less intermediate in character 1866 1869 1872 |
have had a character in some degree intermediate 1859 1860 1861 |
with respect to all existing Marsupials; or that both Rodents and Marsupials branched off from a common progenitor, and that both groups have since undergone much modification in divergent directions. On either view we
may may 1859 1860 1861 1866 | must 1869 1872 |
suppose that the bizcacha has retained, by inheritance, more of the
character character 1859 1860 1861 1866 1869 | characters 1872 |
of its ancient progenitor than have other Rodents; and therefore it will not be specially related to any one existing Marsupial, but indirectly to all or nearly all Marsupials, from having partially retained the character of their common progenitor, or of
an an 1859 1860 1861 1866 | some 1869 1872 |
early member of
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