(_Macropus rufus_)
Little wonder that when Captain Cook and his companions first beheld
kangaroos bounding over the plains of Australia they were overwhelmed
with astonishment, and regarded them as the most extraordinary animals
in the world. They are, indeed, unlike any other creatures, and form
the supreme development of the terrestrial and herbivorous section of
the marsupial type, being admirably adapted to their environment, and
occupying in Australia the place held in other countries by cattle,
sheep, antelopes, deer, and hares. For there are kangaroos of all
sizes, ranging from the gigantic species, with its 6 foot stature,
forming the subject of the present notice, down to the diminutive
kangaroo-rats, no larger than rabbits.
That kangaroos, like all marsupials, bring forth their young in an
exceedingly imperfect and helpless condition, it is almost unnecessary
to mention; as is the fact that the females carry them in the pouch not
only till they are able to take care of themselves, but, on occasion,
till a much later period. Not that it is to be assumed from this that
the young of all marsupials are carried in the maternal pouch; this
being in some cases undeveloped, and the offspring in such instances
merely clinging for a time to their mothers’ nipples.
For a long time it was generally considered that marsupials were
survivors of the ancestral stock which gave rise to the ordinary, and
so-called placental, mammals; but this is now known to be a mistaken
view, and marsupials and placentals are evidently divergent branches
from a common ancestral stock. In Australia marsupials have developed
almost as many different modifications as have the placentals in
other parts of the world; and at first sight there seem few external
characters in common to such diverse types as the leaping, bipedal,
herbivorous kangaroo, and the cursorial and carnivorous Tasmanian wolf.
When, however, the two animals are observed more closely, we may note
a curious resemblance in the form of their heads, and, above all, by
the great, thick tail, passing almost imperceptibly into the body; both
these features proclaiming their comparatively near relationship and
descent from a common ancestor.
Among the external characteristics of the kangaroo tribe may be noted
the somewhat deer-like head, the short fore-limbs, each armed with five
toes, and used in progression only when the animal is grazing, and
the enormous length and strength of the hind-legs, in which one toe
is greatly developed at the expense of the rest, and serves not only
to aid in progression, but forms an offensive weapon of great power
and effectiveness. In the sitting posture, as represented in the
illustration, the body is supported on a tripod formed by the massive
tail and the hind-legs; the whole of the lower portion of the latter,
corresponding structurally to the human foot, being then applied to
the ground. When, however, the animal is leaping, as shown in the
background of the picture, the hind part of the foot is raised and the
body supported by the toes; the tail thumping on the ground at each
leap.
[Illustration]
Kangaroos subsist chiefly on grass and leaves, but also eat buds,
bark, roots, and fruits. Originally they were to be found all over the
habitable parts of Australia and Tasmania, from the coasts inwards, and
while most kinds inhabited the plains, others were to be found in the
mountains. Nowadays, however, they have for the most part been driven
back into the uncultivated lands of the interior, and their numbers
have been greatly reduced. All the larger species associate in large
bands. True kangaroos of the genus _Macropus_ are also found in New
Guinea, while a few of the smaller kinds are natives of the eastern
Austro-Malay Islands.
The great red kangaroo, the subject of the illustration, is the largest
member of the whole group, and takes its name from the dark rusty red
colour of the soft woolly hair of the adult males, that of the females
being a delicate bluish grey. Its home is in the rocky districts of
South and East Australia.
As this species is kept in most Zoological Gardens, opportunities have
been afforded of observing the newly born young. These come into the
world after a gestation of only thirty-nine days, when they are only
about an inch and a quarter in length, and little more than shapeless
lumps of animation. The newborn young is immediately transferred by the
mother, by means of her lips, to the pouch, where it is attached by
its sucking mouth to a nipple. Here it remains for eight months, after
which it returns to the shelter of the pouch, when so disposed, for a
considerable time longer: a fresh offspring being often in the pouch at
the same time.