New Zealand; but I suspect that this exception (if the information be
correct) may be explained through glacial agency. This general absence
of frogs, toads, and newts on so many oceanic islands cannot be
accounted for by their physical conditions; indeed it seems that
islands are peculiarly well fitted for these animals; for frogs have
been introduced into Madeira, the Azores, and Mauritius, and have
multiplied so as to become a nuisance. But as these animals and their
spawn are known to be immediately killed by sea-water, on my view we
can see that there would be great difficulty in their transportal
across the sea, and therefore why they do not exist on any oceanic
island. But why, on the theory of creation, they should not have been
created there, it would be very difficult to explain.
Mammals offer another and similar case. I have carefully searched the
oldest voyages, but have not finished my search; as yet I have not
found a single instance, free from doubt, of a terrestrial mammal
(excluding domesticated animals kept by the natives) inhabiting an
island situated above 300 miles from a continent or great continental
island; and many islands situated at a much less distance are equally
barren. The Falkland Islands, which are inhabited by a wolf-like fox,
come nearest to an exception; but this group cannot be considered as
oceanic, as it lies on a bank connected with the mainland; moreover,
icebergs formerly brought boulders to its western shores, and they may
have formerly transported foxes, as so frequently now happens in the
arctic regions. Yet it cannot be said that small islands will not
support small mammals, for they occur in many parts of the world on
very small islands, if close to a continent; and hardly an island can
be named on which our smaller quadrupeds have not become naturalised
and greatly multiplied. It cannot be said, on the ordinary view of
creation, that there has not been time for the creation of mammals;
many volcanic islands are sufficiently ancient, as shown by the
stupendous degradation which they have suffered and by their tertiary
strata: there has also been time for the production of endemic species
belonging to other classes; and on continents it is thought that
mammals appear and disappear at a quicker rate than other and lower
animals. Though terrestrial mammals do not occur on oceanic islands,
rial mammals do occur on almost every island. New Zealand possesses
two bats found nowhere else in the world: Norfolk Island, the Viti
Archipelago, the Bonin Islands, the Caroline and Marianne
Archipelagoes, and Mauritius, all possess their peculiar bats. Why, it
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