Kangaroos, Opossums And Kin - Part 1

Some animals, such as the colt and the antelope kid, are able to run after their mothers a short while after birth, and they have open eyes and keen senses.

Others such as newborn kittens or mouse babies are blind and helpless, but yet have the strength to draw nourishment from the mother. However, not all baby mammals are able to do even this much for themselves. As humans, that's even true for us.

The newborn youngsters of kangaroos, opossums, and their cousins -- the order Marsupialia -- start life in a very helpless condition. They are born at an early stage of development. They are less than an inch long and look like pink grubs.

Underdeveloped as these babies are, they crawl "hand over hand" through the mother's fur after birth to the nipples, or teats. In most marsupials, there is a pouch of skin on the underside of the mother. This pouch covers the teats and holds and protects the babies.

Too undeveloped even to suck the nourishment it needs, each baby finds a nipple and becomes attached to it. Special muscles in the nipple pump milk into the tiny animals, drop by drop. The baby grows, safe and snug in the pouch.

The babies continue to develop until they look like small copies of their parents. Then, they come out and run around, climbing back into their fur-lined cradle when frightened or tire, and to take their food as long as they need it.

While the baby is extremely small, there is a special arrangement that prevents milk from being forced into the lungs, so that the baby may breathe while attached to the teat. A tube connects the nostrils with the windpipe. The air goes to the lungs without interfering with the food until the young marsupial is old enough to begin sucking.

By far, the largest variety of marsupials live in Australia and the neighboring islands, Tasmania and New Guinea. Once, long ago, they were found also in Europe and Asia, but not the only other regions with marsupial inhabitants are the Americas.

Doubtless there were giant marsupials in Australia once - kangaroo-like and wombat - like creatures the size of rhinoceroses, and odd monsters with teeth like shears. Some day we may even discover fossils of an earlier age, but thus far little is known of the older Australian marsupials.

A few marsupials are found in the East Indies as far away as Celebes and Timor. These are cuscuses - hardy, tree living types that may have been carried on drifting trees across the narrow straits between the islands. Others are thought to have gone east to the Solomon Islands in a similar fashion.

In South America, which, like Australia was also cut off for long ages from the rest of the world, the marsupials flourished. There were great carnivorous marsupials resembling hyenas and saber-tooth tigers before the Panama Isthmus rose out of the sea and joined South with North America.

Modern types of mammals then invaded the continent and the marsupials, except the opossum group and some strange, rate-like forms, became extinct.

Clearly, we can see that marsupials take the place in Australia of other kinds of mammals in the rest of the world. The kangaroos stand in place of the grass eaters -- deer, antelopes, and cattle.

There are tree climbing marsupials like monkeys, with grasping tails. Some spend their lives among the rocks. Others burrow like badgers or woodchucks or tunnel like moles in the earth.

One is an ant eater. Some of the squirrel like phalangers that live in trees have developed folds of skin between the limbs that turn them into gliders.

A few live by killing other mammals and birds. Some feed on insects.

There are mole-like, bear-like, rabbit-like, and mouse-like marsupials. Some are larger than man, while others are as small as field mice.

Beginning with kangaroos -- they do not run or gallop -- when they want to go anywhere in a hurry they leap and bound, the larger kids covering twenty or thirty feet at a jump.

They can clean an ordinary fence with great ease. The big tail acts as a balance and is especially useful in making sharp turns.

The kangaroo's smaller relatives, the wallabies, tree kangaroos and rat kangaroos, are all leapers too, traveling when they are in a hurry by umping with the kind legs.

The front limbs of the kangaroo are small, and they are little used, except when the animal is moving slowly from one food patch to another. At such a time the kangaroo crawls clumsily along the ground. He often uses his stout tail as he would a fifth leg.

The hind legs of this interesting animal are powerful and long. There are only four toes on the hind feet. One, which corresponds to our fourth toe, is large and bears most of the weight.

The slender second and third toes are joined together, all except the claws.

The odd, "frozen-together" condition of these toes is characteristic of the kangaroo, phalanger, wombat and bandicoot families, while other marsupials have all their toes separated.

The head of a kangaroo is amll but reminds one of a deer's or a rabbit's, which large, gentle looking eyes and long ears.

The teeth are peculiar. There are only two lower front teeth, one on each side of the jaw, as in the rodent and rabbit tribes, but the upper front teeth are three or four on either side.

The lower jaw is hinged in the middle. The chewing teeth are cross-ridged, the better to chop and grind up the food.

In the summer of 1770, Captain James Cook, one of the most renowned of Britain's explorers, anchored his good ship the Endeavour at the mouth of a river in New South Wales.

Some of the crew were landed to hunt food and bring fresh water. They brought news of a strange animal which sat upright on its legs and tail and which fled, leaping, across the pain.

This was the first time reported that white men had seen a great gray kangaroo, one of the three larger species we call true kangaroos.

The gray kangaroo can raise itself to a height of seven feet or more, standing on the toes of its great hind limbs. It may weigh two hundred pounds.

The gray kangaroo has a hairy muzzle, which helps distinguish it from related species. The Australians call the gray males "old men," or "boomers". The gray females, are called "flying does. The young are called "joeys."

The red kangaroo is usually a grayish red color, although some individuals are more bluish.

It has a strongly marked black whisker mark.

The red species is almost as large as the great gray kangaroo.

The wallaroo is smaller than the gray and red kangaroos, stouter in build and with shorter limbs.

A large one stands five feet or more in height and may weigh up to 170 pounds. Instead of soft fur of the great kangaroos, the coat of a wallaroo is harsh and shaggy.

Wallabies are small kangaroos. There are many types. The various kinds of wallabies are at home in the scrub and among the rocks.

In addition to grass, they eat many leaves, twigs, and roots. Some species are found in New Guinea and the Bismarck Islands, while their large relatives are confined to the Australian mainland and Tasmania.

The larger wallabies, such as the red-necked, pretty-face, and agile species are some five feet in length, of which the tail is about half, but there are certain kinds of wallabies, that are no larger than rabbits.

One group is called the hare wallabies from their hare-like speed, their habit of crouching low in forms (lairs) and their appearance.

Some rock wallabies have tufted tails, while the nail-tailed wallabies are, with the exception of the lion, the only mammals in which, the tail ends in a horny nail-like spur.

This either has no purpose or science has not been able to guess the use of the spur in either lion or wallaby.

The tree kangaroos are, as their name suggests, very different in their habits from their relatives. The hind legs, although still built for leaping, are shorter and heavier.

The feet, too, are short and broad, with pebbly footpads which assist in climbing and moving about on tree limbs.

The claws are sharp and strong.

In size, tree kangaroos reach about four feet in length, the tail being about two feet. They are good climbers and leap from branch to branch or down to the ground with skill and sureness of footing.

Several species are brilliantly colored. One has bright golden chestnut upper parts and a yellow tail. Other kinds are black, gray, or brownish in color.

Tree kangaroos make their homes in the mountain forests of New Guinea and northern Queensland.

Rat kangaroos belong to a group less like the true kangaroos than even the tree dweller kangaroos.

Their ears are short and rounded and their faces rat like, while their claws are long, and suitable for digging.

The middle upper incisor teeth are large and the grinders have more simple pattern that found in the rest of the kangaroo family.

The largest species is the rufous rat kangaroo, which is about three feet in length.

The brush-tailed species of rat kangaroo is more widespread and common. These have tails that can grasp things and carry grass and leaves when the animals are building nests.

The rat kangaroos should not be confused with the American kangaroo rates, which are rodents although they are shaped like tiny kangaroos.

Rat kangaroos are small cousins of the real kangaroos. They get their name from the fact that they look much like rats.

Although their well developed hind legs are used in leaping and jumping, the rat kangaroos run, using all four legs most of the time.

The musk kangaroo is the smallest of the family. It is also the one lest adapted for leaping.

All the others have only four toes on the hind feet, but this species has five toes.

Musk kangaroos live in the dense brush and forest along the rivers and on the coastal mountains of Queensland.

They often come out in the day time to dig the leaf mold and debris while hunting grubs, insects, and succulent roots on which they feed.