Origin of Species Variorum

→ in 1859 1860 1861 1866

to existing species in 1869 1872

→ will always 1859 1860 1861 1866

will of course 1869

would of course 1872

→ dog, 1859 1860 1861 1866 1869

case of the dog, 1872

→ must 1859 1860 1861 1866

in this latter respect must 1869 1872

→ quickly enough. 1859 1860 1861 1866 1869

still more quickly. 1872

→ sometimes 1859 1860 1861 1866 1869

easily err in 1872

→ which are really of very little importance, and which have originated from quite secondary causes, independently of 1859 1860 1861 1866

which have originated from quite secondary causes, independently of 1869

and in believing that they have been developed through 1872

→ should remember that climate, food, &c., probably have some little direct influence 1859 1860 1861 1866

should remember that climate, food, &c., probably have had some, perhaps a considerable, direct influence 1869

must by no means overlook the effects of the definite action of changed conditions of life,— of so-called spontaneous variations, which seem to depend in a quite subordinate degree 1872

→ organisation; that characters reappear from the 1859 1860 1861 1866 1869

nature of the conditions,— of the tendency to reversion to long-lost characters,— of the complex 1872

→ reversion; that correlation of growth will have had a most important influence in modifying various structures; 1859 1860 1861 1866

reversion; that correlation is an important element of change; 1869

growth, such as of correlation, compensation, of the pressure of one part on another, &c.,— 1872

→ will often have largely modified the external 1859 1860 1861 1866

has often largely modified the external 1869

by which 1872

→ animals having a will, to give one male an advantage in fighting with another or in charming the females. 1859 1860 1861 1866

the higher animals, so as to give one male an advantage in fighting with other males, or in charming the female; and characters gained through sexual selection may be transmitted to both sexes. 1869

use to one sex are often gained and then transmitted more or less perfectly to the other sex, though of no use to this sex. 1872

→ Moreover when a modification of structure has primarily arisen from the above or other unknown causes, it may 1859 1860 1861

Moreover, when a modification of structure has primarily arisen from the above or other unknown causes, it may 1866

Moreover a modification, caused in any of the above specified ways, may 1869

But structures thus indirectly gained, although 1872

→ advantage to the 1859 1860 1861 1866

direct advantage to a 1869

advantage to a 1872

→ the descendants of the species 1859 1860 1861 1866

its descendants 1869

its modified descendants, 1872

former period, have been transmitted →in nearly the same state, although now

~~become~~

become

of very slight use;

but

and

any actually injurious deviations in their structure →will always have been checked by natural selection. Seeing how important an organ of locomotion the tail is in most aquatic animals, its general presence and use for many purposes in so many land animals, which in their lungs or modified swimbladders betray their aquatic origin, may perhaps be thus accounted for. A well-developed tail having been formed in an aquatic animal, it might subsequently come to be worked in for all sorts of

purposes,—

purposes,

as a fly-flapper, an organ of prehension, or as an aid in turning, as

with

the →dog, though the aid →must be slight, for the hare, with hardly any tail, can double →quickly enough.

In the second place, we may →sometimes

wrongly attribute

attributing

attribute

importance to

characters,

characters

→which are really of very little importance, and which have originated from quite secondary causes, independently of natural selection. We →should remember that climate, food, &c., probably have some little direct influence on the →organisation; that characters reappear from the

laws

law

of →reversion; that correlation of growth will have had a most important influence in modifying various structures; and

finally

finally,

that

sexual

selection,

selection

→will often have largely modified the external characters of →animals having a will, to give one male an advantage in fighting with another or in charming the females. →Moreover when a modification of structure has primarily arisen from the above or other unknown causes, it may at first

~~have been~~

have been

of no →advantage to the species,

~~but~~

but

may subsequently have been taken advantage of by →the descendants of the species under new conditions of life and

~~with~~

with

newly acquired habits.

To give a few instances to illustrate these latter