| → a record of the mutations of life, 1859 1860 |
| a record of the mutations of life 1861 1866 |
| was the record in 1869 1872 |
|
| → our not discovering 1859 1860 1861 1866 |
| OMIT 1869 1872 |
|
| → by none more forcibly than by Professor Sedgwick, 1859 |
| by none more forcibly than by Professor Sedgwick— 1860 |
| Sedgwick— 1861 1866 1869 1872 |
|
| → descent with slow modification 1859 1860 1861 1866 1869 |
| evolution 1872 |
|
| → of 1859 1860 1861 1866 1869 |
| by this means of 1872 |
|
| ↑ 1 blocks not present in 1859 1860; present in 1861 1866 1869 1872 |
| In all cases positive palæontological evidence may be implicitly trusted; negative evidence is worthless, as experience has so often shown.
|
|
|
be ranked as distinct species. But I do not pretend that I should ever have suspected how poor
→a record of the mutations of life,
the best
geological
had not the
of
→our not discovering
innumerable transitional links between the species which
at the commencement and close of each formation, pressed so hardly on my theory. |
|
|
| The abrupt manner in which whole groups of species suddenly appear in certain formations, has been urged by several
for instance, by Agassiz, Pictet, and
→by none more forcibly than by Professor Sedgwick,
as a fatal objection to the belief in the transmutation of species. If numerous species, belonging to the same genera or families, have really started into life
at once, the fact would be fatal to the theory of
→descent with slow modification
through natural selection. For the development
→of
a group of forms, all of which
descended from some one progenitor, must have been an extremely slow process; and the
must have lived long
before their modified descendants. But we continually
the perfection of the geological record, and falsely infer, because certain genera or families have not been found beneath a certain stage, that they did not exist before that stage. ↑
We continually forget how large the world is, compared with the area over which our geological formations have been carefully examined; we forget that groups of species may elsewhere have long
and have slowly
before they invaded the ancient archipelagoes of Europe and
the United States. We do not make due allowance for the
intervals of
which have
|
