| Comparison with 1861 |
|
workers, by my giving not the actual measurements, but a strictly accurate illustration: the difference was the same as if we were to see a set of workmen building a house
of whom many were five feet four inches high, and many sixteen feet high; but we must suppose
that the larger workmen had heads four instead of three times as big as those of the smaller men, and jaws nearly five times as big. The jaws, moreover, of the working ants of the several sizes differed wonderfully in shape, and in the form and number of the teeth. But the important fact for us is, that
though the workers can be grouped into castes of different sizes, yet they graduate insensibly into each other, as does the widely-different structure of their jaws. I speak confidently on this latter point, as Mr.
Lubbock made drawings for me
with the camera lucida
of the jaws which I had
dissected from the workers of the several sizes. ↑| 1 blocks not present in 1859 1860 1861; present in 1866 1869 1872 | | Mr. Bates, in his most
interesting 'Naturalist on the Amazons,' has described some
analogous cases.
|
|
|
With these facts before me, I believe that natural selection, by acting on the fertile parents,
could form a species which should regularly produce neuters, either
all of large size with one form of jaw, or all of small size with jaws having a
widely different structure;
or lastly, and this is our
climax of difficulty, one set of workers of one size and structure, and simultaneously
another set of workers of a different size and structure;— a graduated series having been first
formed, as in the case of the driver ant, and then the extreme forms,
from being the most useful to the community,
having been produced in greater and greater numbers
through the natural selection
of the parents which generated them;
until
none with an intermediate structure were produced. ↑| 2 blocks not present in 1859 1860 1861; present in 1866 1869 1872 | | An analogous explanation has been given by Mr. Wallace, of the equally complex case, of certain Malayan Butterflies
regularly appearing at the same time and place
under two or even three distinct female forms; and by Fritz Müller,
of certain Brazilian crustaceans likewise appearing under two widely distinct male forms.
But the
subject need not here be discussed.
|
|
|
| Thus,
as I believe, the wonderful fact of two distinctly defined castes of sterile workers existing in the same nest, both widely different from each other and from
|
workers, by my giving not the actual measurements, but a strictly accurate illustration: the difference was the same as if we were to see a set of workmen building a
house | house 1859 1860 1861 | | house, 1866 1869 1872 |
| suppose 1859 1860 1861 1866 1869 |
| in addition suppose 1872 |
| that 1859 1860 1861 | | that, 1866 1869 1872 |
| Mr. 1859 1860 1861 | | Sir J. 1866 1869 1872 |
| me 1859 1860 1861 | | me, 1866 1869 1872 |
| lucida 1859 1860 1861 | | lucida, 1866 1869 1872 |
| had 1859 1860 1861 | had 1866 1869 1872 |
| 1 blocks not present in 1859 1860 1861; present in 1866 1869 1872 | | Mr. Bates, in his most
interesting 'Naturalist on the Amazons,' has described some
analogous cases.
|
|
|
With these facts before me, I believe that natural selection, by acting on the fertile
parents, | parents, 1859 1860 1861 1866 |
| ants or parents, 1869 1872 |
| either 1859 1860 1861 1866 1869 | either 1872 |
| jaws having a 1859 1860 1861 1866 1869 |
| OMIT 1872 |
| structure; 1859 1860 1861 1866 1869 | | jaws; 1872 |
| our 1859 1860 1861 1866 | | the 1869 1872 |
| simultaneously 1859 1860 1861 1866 1872 |
| at the same time 1869 |
| been first 1859 1860 1861 1866 | | first been 1869 1872 |
| forms, 1859 1860 1861 | | forms 1866 1869 1872 |
| from being the most useful to the community, 1859 1860 1861 |
| OMIT 1866 1869 1872 |
| in greater and greater numbers 1859 1860 1861 |
| in greater and greater numbers, 1869 1872 |
| OMIT 1866 |
| natural selection 1859 1860 1861 1866 | | survival 1869 1872 |
| them; 1859 1860 1861 | | them, 1866 1869 1872 |
| until 1859 1860 1861 1869 1872 |
| in greater and greater numbers, until 1866 |
|
|
Thus, | Thus, 1859 1860 1861 |
| I have now explained how, 1866 1869 1872 |
|
