Origin of Species Variorum

→ owing to oscillations of level, 1859 1860 1861

owing to former oscillations of level, 1866 1869

OMIT 1872

→ have recently 1859 1860 1861

have 1866 1869

owing to former oscillations of level, have 1872

→ most 1859 1860 1861 1866 1869

the greatest number of 1872

→ We 1859 1860 1861 1866 1869

In accordance with this view, we 1872

→ on these views, 1859 1860 1861 1866 1869

OMIT 1872

→ smaller 1859 1860 1861 1866 1869

productions of the smaller 1872

→ have formerly yielded, and apparently are 1859 1860 1861 1866

are 1869

OMIT 1872

→ islands. On a small island, the race for life will have been less severe, and there will have been less modification and less exter- mination. 1860

islands. 1859 1861 1866 1869 1872

there supported, but the conditions of life are

much more

infinitely

complex from the large number of already existing species; and if some of these many species become modified and improved, others will have to be improved in a corresponding

degree,

degree

or they will be exterminated. Each new form, also, as soon as it has been much improved, will be able to spread over the open and continuous area, and will thus come into competition with many

other forms.

others.

Hence more new places will be formed, and the competition to fill them will be more severe, on a large than on a small and isolated area.

More-over,

Moreover,

great areas, though now continuous, →owing to oscillations of level, will

often,

often

→have recently existed in a broken

condition;

condition,

so that the good effects of isolation will generally, to a certain extent, have concurred. Finally, I conclude that, although small isolated areas

~~probably~~

probably

have been in some respects highly favourable for the production of new species, yet that the course of modification will generally have been more rapid on large areas; and what is more important, that the new forms produced on large areas, which already have been victorious over many competitors, will be those that will spread most widely,

and will

will

give rise to →most new varieties and

species.

species,

They

and

will thus play

the most

a more

important part in the changing history of the organic world.

→We can, perhaps, →on these views, understand some facts which will be again alluded to in our chapter on

Geographical

geographical

Distribution;

distribution;

for instance,

~~that~~

that

the

fact

productions

of the →smaller continent of Australia →have formerly yielded, and apparently are now

yielding

yielding,

before those of the larger Europæo-Asiatic area. Thus, also, it is that continental productions have everywhere become so largely naturalised on →islands. On a small island, the race for life will have been less severe, and there will have been less modification and less exter- mination.