| → there is a constant tendency in their characters 1859 1860 1861 1866 1869 |
| they constantly tend 1872 |
|
| → diverge. 1859 1860 1861 1866 1869 |
| diverge in character. 1872 |
|
| → conclusion was 1859 1860 1861 1866 |
| latter conclusion is 1869 1872 |
|
| → less divergent, the 1859 1860 1861 |
| preceding, less divergent and 1866 1869 1872 |
|
| → genera on this 1859 1860 1861 1866 |
| whole of the genera along this upper 1869 1872 |
|
| → though less, in common; 1859 1860 1861 1866 1869 |
| in common, though less than when grouped in sub-families; 1872 |
|
|
species. Consequently the groups which are now large, and which generally include many dominant species, tend to go on increasing
in size. I further attempted to show that from the varying descendants of each species trying to occupy as many and as different places as possible in the economy of nature,
→there is a constant tendency in their characters
to
→diverge. This
→conclusion was
supported by
the great diversity of
forms
which, in any small area, come into the closest competition, and by
certain facts in naturalisation. |
|
| I attempted also to show that there is a
tendency in the forms which are increasing in number and diverging in character, to supplant and exterminate the
→less divergent, the
less
forms. I request the reader to turn to the diagram illustrating the action, as formerly explained, of these several principles; and he will see that the inevitable result
that the modified descendants proceeding from one progenitor become broken up into groups subordinate to groups. In the diagram each letter on the uppermost line may represent a genus including several species; and
the
→genera on this
form together one class, for all
descended from one ancient
and, consequently, have inherited something in common. But the three genera on the left hand have, on this same principle, much in common, and form a sub-family, distinct from that
the next two genera on the right hand, which diverged from a common parent at the fifth stage of descent. These five genera have also
→though less, in common;
and they form a family distinct from that
the three genera still
to the right hand, which diverged at
earlier period. And all these genera,
from (A), form an order distinct from the
|
