| → of the same 1859 1860 1861 1866 |
| OMIT 1869 1872 |
|
| → through natural selection 1859 1860 1861 1866 |
| OMIT 1869 1872 |
|
| ↑ 1 blocks not present in 1859 1860 1861 1866; present in 1869 1872 |
| Another interesting relation exists, namely between the depth of the sea separating islands from each other or from the nearest continents,
and the degree of affinity of their mammalian inhabitants.
|
|
| → in 1859 1860 1861 |
| since fully confirmed by Mr. Wallace's admirable researches, in 1866 |
| since greatly extended by Mr. Wallace's admirable researches, in 1869 1872 |
|
| → are situated on moderately deep 1859 1860 1861 1866 |
| stand on a moderately shallow 1869 1872 |
|
| → closely allied or identical 1859 1860 1861 1866 |
| the same or by very closely allied 1869 |
| the same or by closely allied 1872 |
|
|
no terrestrial mammal can be transported across a wide space of sea, but bats can fly across. Bats have been seen wandering by day far over the Atlantic Ocean; and two North American species either regularly or occasionally visit Bermuda, at the distance of 600 miles from the mainland. I hear from Mr. Tomes, who has specially studied this family, that many
→of the same
species have enormous ranges, and are found on continents and on far distant islands. Hence we have only to suppose that such wandering species have been
→through natural selection
in their new homes in relation to their new position, and we can understand the presence of endemic bats on
with the absence of all
mammals. ↑
|
| Besides the absence of terrestrial mammals in relation to the remoteness of islands from continents, there is also a
to a certain extent independent of distance, between the depth of the sea separating an island from the neighbouring mainland, and the
in both of the same mammiferous species or of allied species in a more or less modified condition. Mr. Windsor Earl has made some striking observations on this
→in
regard to the great Malay Archipelago, which is traversed near Celebes by a space of deep
and this
separates two widely distinct mammalian faunas. On either side the islands
→are situated on moderately deep
submarine
and
are inhabited by
→closely allied or identical
quadrupeds. No doubt some few anomalies occur in this great archipelago, and there is much difficulty in forming a judgment in some cases owing to the probable naturalisation of certain mammals through man's agency; but we shall soon have much light thrown on the natural history of this archipelago by the admirable zeal and researches of Mr. Wallace. I have not as yet had time to
|
