Origin of Species Variorum

→ like 1859 1860 1861

into it like 1866 1869 1872

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

Even in so extreme a case as this, if the supply of insects were constant, and if better adapted competitors did not already exist in the country, I can see no difficulty in a race of bears being rendered, by natural selection, more and more aquatic in their structure and habits, with larger and larger mouths, till a creature was produced as monstrous as a whale.

→ of a species 1859 1860 1861 1866 1869

OMIT 1872

→ of their own 1860 1861 1866 1869

both of their own 1859

proper to their 1872

→ on my theory, 1859 1860 1861 1866

OMIT 1869 1872

→ which in every essential part of its organisation, even in its colouring, 1859 1860

( Colaptes campestris ) which has two toes before and two behind, a long pointed tongue, stiff pointed tail feathers, but not so stiff as 1861

( Colaptes campestris ) which has two toes before and two behind, a long pointed tongue, stiff pointed tail-feathers, but not so stiff as 1866

( Colaptes campestris ) which has two toes before and two behind, a long pointed tongue, pointed tail-feathers, sufficiently stiff to support the bird in a vertical position on a post, but not so stiff as 1869

(Colaptes campestris) which has two toes before and two behind, a long pointed tongue, pointed tail-feathers, sufficiently stiff to support the bird in a vertical position on a post, but not so stiff as 1872

→ harsh tone of its voice, and undulatory flight, told me plainly of its close blood-relationship to our common species; yet it is a woodpecker which never climbs a tree! 1859 1860

typical woodpeckers (yet I have seen it use its tail when alighting vertically on a post), and a straight strong beak. 1861 1866

typical woodpeckers, and a straight strong beak. 1869 1872

and then proceeding to another, like a kestrel, and at other times standing stationary on the margin of water, and then dashing →like a kingfisher at a fish. In our own country the larger titmouse (Parus major) may be seen climbing branches, almost like a creeper; it

sometimes,

often,

like a shrike, kills small birds by blows on the head; and I have many times seen and heard it hammering the seeds of the yew on a branch, and thus breaking them like a nuthatch. In North America the black bear was seen by Hearne swimming for hours with widely open mouth, thus catching,

almost like

a whale, insects in the water. ↑

As we sometimes see individuals →of a species following habits

~~widely~~

widely

different from those →of their own species and

the other species of the same genus, we might

expect

expect,

→on my theory, that such individuals would occasionally

~~have~~

have

give

given

rise to new species, having anomalous habits, and with their structure either slightly or considerably modified from that of their

~~proper~~

proper

type. And such instances

occur in nature. Can a more striking instance of adaptation be given than that of a woodpecker for climbing trees and

~~for~~

for

seizing insects in the chinks of the bark? Yet in North America there are woodpeckers which feed largely on fruit, and others with elongated wings which chase insects on the

wing.

wing;

and on

the plains of La Plata, where

hardly

not

a tree grows, there is a

woodpecker

woodpecker,

→which in every essential part of its organisation, even in its colouring, in the →harsh tone of its voice, and undulatory flight, told me plainly of its close blood-relationship to our common species; yet it is a woodpecker which never climbs a tree!

Petrels are the most

aërial

and oceanic of birds,

but

yet

in the quiet

sounds

Sounds

of Tierra del Fuego, the Puffinuria berardi, in its general habits, in its astonishing power of diving,

in its

its

manner of

swimming

swimming,

and of flying when