Origin of Species Variorum

→ to find that 1869 1872

that 1859 1860 1861 1866

→ OMIT 1869 1872

the changed conditions of 1859 1860 1861 1866

→ species present 1869 1872

there are at least 1859 1860 1861 1866

→ admit that natural varieties exist, which are considered 1872

have admitted the existence of varieties, which they think 1859 1860

have admitted the existence of varieties, which they have considered 1861 1866

admit that varieties exist, which are considered 1869

→ outlying islands, 1869 1872

the several islands in the same archipelago, 1866

↑ 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 slightly or slowly, 1872

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 slowly or so little, 1866

animals and plants do vary, let it be ever so little or so slowly, 1869

→ not variations or individual differences, which are 1872

we doubt that variations 1859 1860 1861 1866

we doubt that the variations or individual differences, which are 1869

→ beneficial, 1872

useful to beings, under their excessively complex relations of life, would 1859 1860 1861

useful to them under their extremely complex relations of life would 1866

beneficial would 1869

→ be preserved and accumulated through natural selection, or the survival of the fittest? 1869 1872

be preserved, accumulated, and inherited? 1859 1860 1861

occasionally occur, and then be preserved and accumulated by natural selection? 1866

→ him, why, 1869 1872

himself, should nature fail in selecting variations useful, 1859 1860 1861

himself, should nature fail in preserving or selecting variations useful, 1866

→ and complex conditions 1869 1872

conditions 1859 1860 1861 1866

→ should not variations useful to nature's 1872

to her 1859 1860 1861 1866

should not variations useful to natures 1869

→ products often arise, and be preserved or selected? 1869 1872

products? 1859 1860 1861 1866

→ the highest degree 1872

itself 1859 1860 1861 1866 1869

physical changes, we might have expected →to find that organic beings

would

....

have varied under nature, in the same way as they

generally

....

have varied under →OMIT domestication. And if there

has been

any variability under nature, it would be an unaccountable fact if natural selection

did

had

not come into play. It has often been asserted, but the assertion is

quite

....

incapable of proof, that the amount of variation under nature is a strictly limited quantity. Man, though acting on external characters alone and often capriciously, can produce within a short period a great result by adding up mere individual differences in his domestic productions; and every one admits that →species present individual

differences

species

under

nature.

But, besides such differences, all naturalists →admit that natural varieties exist, which are considered sufficiently distinct to be worthy of record in

their systematic

systematic

works. No one

can

has

draw

drawn

any clear distinction between individual differences and slight varieties; or between more plainly marked varieties and sub-species, and species. On separate continents, and on different parts of the same continent when divided by barriers of any kind, and on →outlying islands, what a

host

multitude

of forms exist, which some experienced naturalists rank as

mere varieties,

varieties,

others as geographical races or sub-species, and others as distinct, though closely allied species! ↑

then

then,

→animals and plants do vary, let it be ever so slightly or slowly, why should →not variations or individual differences, which are in

some

any

way →beneficial, →be preserved and accumulated through natural selection, or the survival of the fittest?

Why, if

man can by patience select variations

most

....

useful to →him, why, under changing →and complex conditions of life, →should not variations useful to nature's living →products often arise, and be preserved or selected? What limit can be put to this power, acting during long ages and rigidly scrutinising the whole constitution, structure, and habits of each creature,— favouring the good and rejecting the bad? I can see no limit to this power, in slowly and beautifully adapting each form to the most complex relations of life. The theory of natural selection, even if we

looked

look

further

farther

than this, seems to

me to

....

be in →the highest degree probable. I have already recapitulated, as fairly as I could, the opposed difficulties and objections: now let us turn to the special facts and arguments in favour of the theory.

On the view that species are only strongly marked and permanent varieties, and that each species first existed as a variety, we can see why it is that no line of demarcation can be drawn between species, commonly supposed to have been produced by special acts of creation, and varieties which are acknowledged to have been