| → the several islands in the same archipelago, 1866 |
| outlying islands, 1869 1872 |
|
| ↑ 1 blocks not present in 1866 1869 1872; present in 1859 1860 1861 |
| Let it be observed how naturalists differ in the rank which they assign to the many representative forms in Europe and North America.
|
|
| → animals and plants do vary, let it be ever so slowly or so little, 1866 |
| we have under nature variability and a powerful agent always ready to act and select, 1859 1860 |
| we have variability as well as a powerful agent always ready to act, 1861 |
| animals and plants do vary, let it be ever so little or so slowly, 1869 |
| animals and plants do vary, let it be ever so slightly or slowly, 1872 |
|
| → we doubt that variations 1859 1860 1861 1866 |
| we doubt that the variations or individual differences, which are 1869 |
| not variations or individual differences, which are 1872 |
|
| → useful to them under their extremely complex relations of life would 1866 |
| useful to beings, under their excessively complex relations of life, would 1859 1860 1861 |
| beneficial would 1869 |
| beneficial, 1872 |
|
| → occasionally occur, and then be preserved and accumulated by natural selection? 1866 |
| be preserved, accumulated, and inherited? 1859 1860 1861 |
| be preserved and accumulated through natural selection, or the survival of the fittest? 1869 1872 |
|
| → himself, should nature fail in preserving or selecting variations useful, 1866 |
| himself, should nature fail in selecting variations useful, 1859 1860 1861 |
| him, why, 1869 1872 |
|
| → conditions 1859 1860 1861 1866 |
| and complex conditions 1869 1872 |
|
| → to her 1859 1860 1861 1866 |
| should not variations useful to natures 1869 |
| should not variations useful to nature's 1872 |
|
| → products? 1859 1860 1861 1866 |
| products often arise, and be preserved or selected? 1869 1872 |
|
| → itself 1859 1860 1861 1866 1869 |
| the highest degree 1872 |
|