Origin of Species Variorum

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

Thus, a well-flavoured vegetable is cooked, and the individual is destroyed; but the horticulturist sows seeds of the same stock, and confidently expects to get nearly the same variety; breeders of cattle wish the flesh and fat to be well marbled together; the animal has been slaughtered, but the breeder goes with confidence to the same family.

→ may be placed in 1866 1869 1872

in 1859 1860 1861

→ OMIT 1872

I do not doubt that 1859 1860 1861

probably 1866 1869

→ it is probable, be 1872

be slowly 1859 1860 1861 1866 1869

→ OMIT 1872

of various colours, 1866 1869

→ but they likewise 1872

so that, if the variety had not yielded others, it would at once have become extinct; but it likewise always 1866

so that, if the variety had not likewise yielded others, it would at once have become extinct; but it always 1869

→ OMIT 1872

only 1866

from ordinary single varieties only 1869

→ OMIT 1872

two forms, from ordinary single varieties. 1866

the two forms. 1869

→ These latter, by which alone the variety can be propagated, 1872

these single and fertile plants 1866

the fertile plants 1869

→ may 1866 1872

producing single flowers may 1869

→ ants, 1872

of an ant-community, 1866 1869

→ double sterile plants 1872

sterile double-flowered plants, which are regularly produced in large numbers, 1866 1869

→ Hence we may conclude that 1872

Thus I believe it has been with social insects: a 1859 1860 1861 1866 1869

→ have proved advantageous: 1872

has been advantageous to the community: 1859 1860 1861 1866 1869

→ have 1872

of the same community 1859 1860 1861 1866 1869

→ OMIT 1872

And I believe that 1859 1860 1861 1866 1869

→ many times, until 1872

until 1859 1860 1861 1866 1869

certain members of insect-communities: the difficulty lies in understanding how such correlated modifications of structure could have been slowly accumulated by natural selection.

This difficulty, though appearing insuperable, is

les- sened,

lessened,

or, as I believe, disappears, when it is remembered that selection may be applied to the family, as well as to the individual, and may thus gain the desired end. Breeders of cattle wish the flesh and fat to be well marbled together: an animal thus characterised has been slaughtered, but the breeder has gone with confidence to the same stock and has succeeded. ↑

I have

....

such

Such

faith →may be placed in the

powers

power

of selection, that →OMIT a breed of cattle, always yielding oxen with extraordinarily long horns,

could

could,

→it is probable, be formed by carefully watching which individual bulls and cows, when matched, produced oxen with the longest horns; and yet no one ox

could

would

ever have propagated its kind. Here is a better and real illustration: according to M. Verlot, some varieties of the double annual

stock

Stock

→OMIT from having been long

carefully

and carefully

selected to the right degree, always produce

by seed

....

a large proportion of

plants

seedlings

bearing double and quite sterile flowers; →but they likewise

yields

yield

some single and fertile

plants,

which

differ

→OMIT

their

power

producing

→OMIT

Thus

....

→These latter, by which alone the variety can be propagated, →may be compared with the

males

fertile male

and

females

female

→ants, and the →double sterile plants with the

many sterile

....

neuters of the same community. As with the varieties of the stock, so with social insects, selection has been applied to the family, and not to the individual, for the sake of gaining a serviceable end. →Hence we may conclude that slight

modification

modifications

structure,

structure

instinct,

of instinct,

correlated with the sterile condition of certain members of the community, →have proved advantageous: consequently the fertile males and females →have flourished, and transmitted to their fertile offspring a tendency to produce sterile members

having

with

the same

modification.

modifications.

→OMIT

this

This

process

has

must have

been

repeated,

repeated

→many times, until that prodigious amount of difference between the fertile and sterile females of the same species has been produced, which we see in

so many

many

social insects.

But we have not as yet touched on the climax of the difficulty; namely, the fact that the neuters of several ants differ, not only from the fertile females and males, but from each other, sometimes to an almost incredible degree, and are thus divided into two or even three castes. The castes, moreover, do not

generally

commonly

graduate into each other, but are perfectly well defined; being as distinct from each

other,

other

as are any two species of the same genus, or rather as any two genera of the same family. Thus in Eciton, there are working and soldier neuters, with jaws and instincts extraordinarily