Origin of Species Variorum

→ fore-leg 1860 1861 1866 1869 1872

fore leg of 1859

→ to 1859 1860 1861 1866 1869

webbed feet no doubt were as useful to 1872

→ webbed feet no doubt were as useful 1859 1860 1861 1866 1869

OMIT 1872

→ which have been inherited from a common progenitor, were formerly 1859 1860 1861 1866

which have been in- herited from some ancient progenitor, were formerly 1869

were originally developed, on the principle of utility, probably through the reduction 1872

→ special use to that progenitor, or its progenitors, than they now are to these animals having such widely diversified habits. 1859 1860 1861 1866

special use than they now are to these animals with their widely diversified habits, and might consequently have been modified through natural selection. 1869

numerous bones in the fin of some ancient fish-like progenitor of the whole class. 1872

↑ 1 blocks not present in 1859 1860 1861 1866 1869; present in 1872

It is scarcely possible to decide how much allowance ought to be made for such causes of change, as the definite action of external conditions, so-called spontaneous variations, and the complex laws of growth; but with these important exceptions, we may conclude that the structure of every living creature either now is, or was formerly, of some direct or indirect use to its possessor.

→ Therefore 1859 1860 1861 1866

Making due allowance for the definite action of changed conditions, correlation, reversion, &c., 1869

→ these several bones might have been acquired through natural selection, subjected formerly, as now, to the several 1859 1860 1861 1866

every detail of structure in every living creature is either now or was formerly of use,—directly or indirectly through the complex 1869

→ inheritance, reversion, correlation of growth, &c. Hence every detail of structure in every living creature (making some little allowance for the direct action of physical conditions) may be viewed, either as having been of special use to some ancestral form, or as being now of special use to the descendants of this form— either directly, or indirectly through the complex laws of growth. 1859 1860

inheritance, reversion, correlation of growth, &C. Hence every detail of structure in every living creature (making some little allowance for the direct action of physical conditions) may be viewed, either as having been of special use to some ancestral form, or as being now of special use to the descendants of this form— either directly, or indirectly through the complex laws of growth. 1861

inheritance, reversion, correlation of growth, &C. Hence every detail of structure in every living creature (making some little allowance for the direct action of physical conditions) may be viewed, either as having been of special use to some ancestral form, or as being now of special use to the descendants of this form—either directly, or indirectly through the complex laws of growth. 1866

growth. 1869

goose or of the frigate-bird are of special use to these birds; we cannot believe that the

similar

same

bones in the arm of the monkey, in the →fore-leg

the

of the

horse, in the wing of the bat, and in the flipper of the seal, are of special use to these animals. We may safely attribute these structures to inheritance. But →to the progenitor of the upland goose and of the frigate-bird, →webbed feet no doubt were as useful as they now are to the most aquatic of

living

existing

birds. So we may believe that the progenitor of the seal

did

had

not

possess a

flipper, but a foot with five toes fitted for walking or grasping; and we may further venture to believe that the several bones in the limbs of the monkey, horse, and bat, →which have been inherited from a common progenitor, were formerly of more →special use to that progenitor, or its progenitors, than they now are to these animals having such widely diversified habits. ↑ →Therefore we may

conclude

infer

that →these several bones might have been acquired through natural selection, subjected formerly, as now, to the several laws of →inheritance, reversion, correlation of growth, &c. Hence every detail of structure in every living creature (making some little allowance for the direct action of physical conditions) may be viewed, either as having been of special use to some ancestral form, or as being now of special use to the descendants of this form— either directly, or indirectly through the complex laws of growth.

Natural selection cannot possibly produce any modification in

any one

species exclusively for the good of another species; though throughout nature one species incessantly takes advantage of, and profits by, the

structures

structure

others.

another.

But natural selection can and does often produce structures for the direct injury of other

animals,

species,

as we see in the fang of the adder, and in the ovipositor of the ichneumon, by which its eggs are

depo- sited

deposited

depo- sisted