Origin of Species Variorum

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

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.

→ owing to former oscillations of level, 1866 1869

owing to oscillations of level, 1859 1860 1861

OMIT 1872

→ have 1866 1869

have recently 1859 1860 1861

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

→ are 1869

have formerly yielded, and apparently are 1859 1860 1861 1866

OMIT 1872

→ islands. 1859 1861 1866 1869 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

→ On a small island, the race for life will have been less severe, and there will have been less modification and less extermination. 1861 1866 1869 1872

On a small island, the race for life will have been less severe, and there will have been less modification and less exter- mination. 1859

Hence, perhaps, it comes that the flora of Madeira, according to Oswald Heer, resembles the extinct tertiary flora of Europe. 1860

→ Hence, perhaps, it is that the flora of Madeira, according to Oswald Heer, resembles the extinct tertiary flora of Europe. 1869

Hence, perhaps, it comes that the flora of Madeira, according to Oswald Heer, resembles the extinct tertiary flora of Europe. 1859 1861 1866

All fresh-water basins, taken together, make a small area compared with that of the sea or of the land; and, consequently, the competition between fresh-water productions will have been less severe than elsewhere; new forms will have been more slowly formed, and old forms more slowly exterminated. 1860

Hence, we can understand how it is that the flora of Madeira, according to Oswald Heer, resembles to a certain extent the extinct tertiary flora of Europe. 1872

→ All fresh-water basins, taken together, make a small area compared with that 1859 1861 1866 1869 1872

And it is in fresh water that we find seven genera of Ganoid fishes, remnants of a once preponderant order: and in fresh water we find some 1860

→ sea or of the land; and, consequently, the competition between fresh-water productions will have been less severe than elsewhere; new forms will have been more slowly formed, and old forms more slowly exterminated. 1859 1861 1866 1869

most anomalous forms now known in the world, as the Ornithorhynchus and Lepidosiren, which, like fossils, connect to a certain extent orders now widely separated in the natural scale. 1860

sea or of the land. Consequently, the competition between fresh-water productions will have been less severe than elsewhere; new forms will have been then more slowly produced, and old forms more slowly exterminated. 1872

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.

↑

More-over,

Moreover,

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

often,

often

→have 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

a more

the most

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 →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 extermination. →Hence, perhaps, it is that the flora of Madeira, according to Oswald Heer, resembles the extinct tertiary flora of Europe. →All fresh-water basins, taken together, make a small area compared with that of the →sea or of the land; and, consequently, the competition between fresh-water productions will have been less severe than elsewhere; new forms will have been more slowly formed, and old forms more slowly exterminated.