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Chapter 1
Mammals
The peak of vertebrate adaptability
There are about 4,000 species of mammal, which are the most adaptable and diverse group of vertebrates on our planet today. Whales, dolphins and seals are important members of the animal community in the seas, while forms such as otters and beavers are successful in freshwater habitats. On dry land, a huge diversity of mammal types prospers underground, on the land surface and in trees and other vegetation. Mammals have even taken to the air in the form of bats, the night-flying insectivores. In all these niche types, mammals reveal a startling variability in feeding strategies: some feed only on plant material, others on small invertebrates. Many kill and eat other vertebrates, including mammals, while some eat almost anything. To begin to understand the reasons for the adaptability and success of mammalian lines of evolution, it is necessary to look at what a mammal is, how it is constructed, how it operates physically and behaviorally and what its ancestors were like.
A mammal is an endothermic (warm-blooded), four-limbed, hairy vertebrate (an animal with a backbone). Male mammals inseminate females internally, using a penis, and females, typically, retain their developing fetuses within the uterus, where the bloodstreams of mother and offspring come close together (but do not fuse) in a placenta. The time spent in the womb by the developing fetus is known as the gestation period and varies from group to group. Some mammals, such as rabbits, rodents and many carnivores, are born naked, blind and helpless while others, such as cattle and deer, are small, but fully formed and capable, versions of the adult. Mothers produce milk for their young from skin-derived mammary glands.
The vast majority of mammals possess these characteristics, but a few exceptions, real and apparent, must be taken into account. Whales and their relatives and manatees have only forelimbs. There is no doubt, however, from their skeletal structure, that these highly modified aquatic animals are derived from four-legged ancestors. However, the monotremes -- the platypus and echidnas -- are highly uncharacteristic mammals. They have retained the egg-laying habits of their reptilian ancestor and do not form placentas. The pouched mammals, or marsupials, also have a method of reproduction that differs from that of the placenta-forming mammals. Kangaroos, wallabies and their relatives retain a thin shell around the developing young inside the mother's body, but it breaks down before the offspring emerges to crawl into the pouch and attach itself to a milk-delivering nipple. Some species do have a primitive placenta. The marsupial young is born in a far less advanced state than most mammals and finishes its development in the pouch.
Knowledge of the ancestry of mammals is based largely on the study of fossil remains of parts of skeletons. Mammals evolved from reptiles about 220 million years ago. During the "age of dinosaurs" between 230 and 65 million years ago, mammals remained small and were shrewlike in appearance and lifestyle. When the dinosaurs became extinct 65 million years ago, the mammals adapted to the wide range of habitats and niches vacated by the extinct reptiles. The mammals have continued their explosive expansion into different types of life and environment to become the dominant group of land-dwelling vertebrates and an important part of aquatic life.
Apart from reproductive sophistication, mammals are remarkable in a number of ways. They have large, complex brains, and acute and well-integrated sensory systems. They employ a range of vocal, visual and olfactory means of communication with other species and with members of their own species -- communication with the latter is important in the organization of family and social groupings. The keratinous hairs that grow out of mammalian skin insulate the body and are part of a complex of temperature-regulation mechanisms with which mammals maintain a constant, high body temperature, irrespective of external climatic conditions. Metabolic heat, especially that produced by brown fat in the body, can be used to offset heat losses and can be transferred around the body via the circulatory system, which is powered by the four-chambered heart. The body can be cooled by the evaporation of sweat secretions at the body surface. All this temperature-control "machinery" is under the control of the hypothalamus in the brain. When temperature control becomes energetically impossible, for example in low temperatures, some mammals are able to hibernate.
During the hibernatory sleep, the animal's body temperature drops to close to that of the surroundings, and its heart and respiration slow dramatically so that it uses the minimum of energy. Thus it is able to survive for as long as several months on stored fat.
The astonishing diversity of present day mammals is illustrated in the following pages, which review each living family and describe representative examples. Briefly, the range of types is as follows. The primitive monotremes and the marsupials -- the majority of which are found in Australia -- have already been mentioned. Australia separated from the southern continents before it could receive any eutherian mammals. Thus the marsupial mammal fauna was able to radiate into a diverse range of forms which mirrors the types of placental mammals found in the rest of the world. There are burrowing, tree-dwelling, ant-eating, herbivorous and predatory marsupials, and marsupial analogues exist or have existed for almost all placental mammals except bats, whales and seals.
The placental mammals form a diverse and successful group that includes the insectivores such as shrews, hedgehogs and moles, bats, sloths, anteaters, armadillos, pangolins, primates (to which humans belong), rodents, rabbits, whales, dolphins and porpoises, carnivores (cats, dogs, mustelids and bears), seals, aardvark, elephants, hyraxes, manatees and the dugong, uneven-toed hoofed mammals such as tapirs, horses and rhinoceroses, and the even-toed (cloven-hoofed) hoofed mammals such as pigs, peccaries, camels, deer, cattle, sheep and goats.
The evolutionary success of the mammals is hard to evalutate. As measured by the dominance of a particular group or its species diversity, success must be the result of an amalgam of intrinsic biological merit and chance. But no other major class of vertebrates has ever conquered such a variety of habitats so completely. The advent of modern humans has probably increased the rate of mammalian extinctions in some groups, but others, such as the rodents, are evolving into new ecological niches created by man's activities. At the present time, the mammals are an overwhelmingly successful group, and it may be true that its most dominant species -- man -- holds the future of the planet in his hands.
ECHIDNAS AND PLATYPUS
ORDER MONOTREMATA
Two families with a combined total of only 3 living species make up this order. Although well-adapted for their environments, monotremes are considered primitive mammals in that they retain some reptilian characteristics of body structure and they lay eggs. However, they also possess the essential mammalian characteristics of body hair and mammary glands. Monotremes are probably a parallel development, rather than a stage in the evolution of mammals. A problem in understanding the origins of this order is that no fossil monotremes have been found.
Tachyglossidae: Echidna Family
There are 2 species of echidna, previously known as spiny anteater. Both are covered with coarse hairs, and their backs are set with spines. They have elongated, slender snouts and strong limbs and are powerful diggers. Echidnas, like other anteating species have no teeth and very weak jaws. Termites, ants and other small arthropods are swept into the mouth by a long, sticky tongue, which can reach well beyond the tip of the snout. The insects are then crushed between the tongue and the roof of the mouth.
Long-beaked Echidna Zaglossus bruiini
Range New Guinea
Habitat Forest
Size Body: 17-30 in (45-77 cm) Tail: vestigial
The long-beaked echidna is larger than the short-beaked and has fewer, shorter spines scattered among its coarse hairs. The snout is two-thirds of the head length and curves slightly downward. There are five digits on both hind and forefeet, but on the former, only the three middle toes are equipped with claws. Males have a spur on each of the hind legs. This echidna is primarily a nocturnal animal that forages for its insect food on the forest floor.
The breeding female has a temporary abdominal brood patch, in which her egg is incubated and in which the new born young remains in safety., feeding and developing. Little is known about the life of this rarely seen animal, but it is believed to have similar habits to those of the short-beaked echidna.
There were once thought to be 3 species in this genus, but now all are believed to be races of this one species. The population of echidnas in New Guinea is declining because of forest clearance and overhunting, and the animal is much in need of protection.
Short-beaked Echidna Tachyglossus aculeatus
Range Australia, Tasmania, S.E. New Guinea
Habitat Grassland, forest
Size Body: 13 3/4-19 3/4 in (35-40 cm) Tail: 3 1/2 in (9 cm)
The short-beaked echidna has a compact, round body, closely set with spines. At the end of its naked snout is a small, slitlike mouth, through which its long tongue is extended 6 to 7 in (15 to 18 cm) beyond the snout. The tongue is coated with sticky saliva, so that any insect it touches is trapped. Echidnas have no teeth but break up their food between horny ridges in the mouth. Termites, ants and other small invertebrates form their main diet.
Echidnas have five digits, all equipped with strong claws, on both hind and forefeet. Males also have spurs on each hind leg which may be used in defense. They are excellent diggers and, if in danger, they will rapidly dig themselves into the ground. However, they do not live in burrows, but in hollow logs or among roots and rocks. The echidnas' capacity for temperature regulation is poor, and in cool weather they hibernate.
On her abdomen, the breeding female has a temporary patch, or groove, which develops at the start of the breeding season. When she has laid her leathery-shelled egg, she transfers it to the patch, where it incubates for between 7 and 10 days. The egg is coated with sticky mucus which helps it to stay in the groove. When the young echidna hatches, it is only 1/2 in (1.25 cm) long and helpless, so it must remain on the mother's abdomen while it develops.
The female produces plenty of milk from mammary glands but she has no nipples, so the baby feeds by sucking on specially adapted areas of abdominal skin through which the milk flows. Once the spines develop, at about 3 weeks, the young is no longer carried by its mother.
Ornithorhyncidae: Platypus Family
The single species of this family is an extraordinary animal in appearance, due to the strange combination of a beak, fur and webbed feet, but it is perfectly adapted for its way of life.
The platypus was discovered 200 years ago, and when the first specimen arrived at London's Natural History Museum, scientists were so puzzled by it that they believed the specimen to be a fake.
Platypuses are now protected by law and are quite common in some areas.
Playpus Ornithorhynchus anatinus
Range Australia, Tasmania
Habitat Lakes, rivers
Size Body: 18 in (46 cm) Tail: 7 in (18 cm)
The platypus is a semi-aquatic animal, and many of its physical characteristics are adaptations for its life as a freshwater predator. Its legs are short but powerful, and the feet are webbed, though the digits retain large claws, which are useful for burrowing. On the forefeet the webs extend beyond the claws and make efficient paddles. On land, however, the webbing can be folded back in order to free the claws for digging.
On each ankle the male platypus has a spur which is connected to poison glands in the thighs. These spurs are used against an attacker or against a competing platypus, but they are never used against prey. The poison is not fatal to man, but does cause intense pain.
The platypus's eye and ear openings lie in furrows, which are closed off by folds of skin when the animal is submerged. Thus, when hunting under water, the platypus relies on the sensitivity of its leathery bill -- which is sensitive to both touch and electric currents produced by prey -- to find its prey. The nostrils are toward the end of the upper bill but can only function when the platypus's head is in air. Young platypuses have teeth, but adults have horny, ridged plates on both sides of the jaws which are used for crushing prey.
The platypus feeds mainly at the bottom of the water, making dives lasting for a minute or more in order to probe the mud with its bill for crustaceans, aquatic insects and larvae. It also feeds on frogs and other small animals and on some plants. Platypuses have huge appetites, consuming up to 2 1/4 lb (1 kg) of food each night.
Short burrows, dug in the river bank above the water level, are used by the platypus for refuge or during periods of cool weather. In the breeding season, however, the female digs a burrow 40 ft (12 m) or more in length, at the end of which she lays her clutch of 2 or 3 eggs on a nest of dry grass and leaves the rubbery eggs are cemented together in a raft. She plugs the entrance to the burrow with moist plant matter, and this prevents the eggs from drying out during the 7- to 14-day incubation period.
When the young hatch, they are only about 1 in (2.5 cm) long and helpless. Until they are about 5 months old, they feed on milk, which issues from slits in the mother's abdominal wall. Unlike echidnas, they do not draw up tucks of skin into pseudonipples, but simply lap and suck the milk off their mother's abdominal fur.
OPOSSUMS AND COLOCOLO
INFRACLASS METATHERIA
Marsupial Mammals
There are 260 species of marsupial mammals in North and South America and in Australasia east of Wallace's line (an imaginary line drawn between Borneo and Sulawesi, and Bali and Lombok). Marsupials evolved at about the same time as the true (placental) mammals, but were replaced by them over much of their range. Australia has only marsupial mammals because it separated from the ancient southern continents of Gondwanaland after it had been populated by early marsupials, but before placental mammals arrived. In Australia marsupials have realized their true potential and have adapted to a variety of ecological niches and have exploited all available habitats.
The principal characteristic of marsupial mammals is their reproduction. Instead of retaining young inside the uterus until they are well developed, as in placental mammals, the gestation period is extremely short -- as brief as 11 days -- and the young finish their development inside a pouch on the mother's belly.
ORDER DIDELPHIMORPHA
Dideliphidae: Opossum Family
This order contains the opossum family only. There are more than 70 species of opossum and they are found from the southern tip of South America northward to southeast Canada. Opossums are all basically rat-shaped animals, with scaly almost hairless tails and rather unkempt fur. Some species possess a proper pouch, while others carry their young between two flaps of skin on the belly.
Most opossums are forest dwellers, although one exceptional species has taken to an aquatic way of life. They feed on leaves, shoots, buds and seeds, and insects may also be eaten.
Pale-Bellied Mouse Opossum Marmosa robinsoni
Range Belize to N. W. South America
Trinidad, Tobago, Grenada
Habitat Forest, dense scrubland
Size Body: 6 1/2-7 1/4 in (16.5-18.5 cm) Tail: 10 1/4-11 in (26-28 cm)
The mouse oposum has a long, pointed nose and huge eyes, which indicate its nocturnal way of life. This opossum is more shrewlike than mouselike in appearance. It makes no permanent home, but constructs temporary daytime nests in tree holes or old birds' nests.
An agile climber, the mouse opossum uses its long, prehensile tail as a fifth limb.
Mouse opossums breed two or three times a year, and litters of up to 10 young are born after a gestation period of 17 days. The young must cling to the mother's fur as she moves around, since mouse opossums do not have proper pouches.
Virginia Opossum Didelphis virginiana
Range S.E. Canada through USA to Central America: Nicaragua
Habitat Forest, scrubland
Size Body: 12 3/4-19 3/4 in (32.5-50 cm) Tail: 10-21 in (25.5-53.5 cm)
The only marsupial found north of Mexico and the largest of the opossum family, the Virginia opossum may weigh up to 12 lb (5.5 kg). It is a successful creature, which has adapted to modern life, scavenging in refuse tips and bins. Should this creature be threatened, by a dog, bobcat, eagle or mink for example, it may react by feigning death. This habit of "playing possum" may result in the predator losing interest or give the opossum vital seconds to make its escape.
In Canada, opossums breed once a year, in spring, but in the south of the range, two or even three litters of 8 to 18 young may be produced in a year. Usually only about 7 of a litter survive pouch life. In the southern USA, opossums are trapped by man for their fur and flesh.
Water Opossum/Yapok Chironectes minimus LR:nt
Range Mexico, south through Central and South America to Argentina
Habitat Freshwater lakes and streams
Size Body: 10 1/2-12 3/4 in (27-32.5 cm) Tail: 14 1/2-15 3/4 in (36-40 cm)
The water opossum, or yapok, is the only marsupial to have adapted to aquatic life. It lives in bankside burrows, emerging after dusk to swim and search for fish, crustaceans and other invertebrates, which it carries to the riverbank to eat. The opossum's long tail helps to control its movement through water.
It uses its broadly webbed hind feet to propel itself through the water. Its fur is oily and water repellant.
In December, water opossums mate, and produce a litter of about 5 young, born some 2 weeks later. The fur-lined pouch is closed by a strong ring of muscle and fatty secretions create a water-tight seal so that the young inside remain quite dry, even when the mother is totally immersed in water. It is not known how the young obtain sufficient oxygen in their hermetically sealed environment.
Short-tailed Opossum Monodelphis brevicaudata
Range Venezuela and The Guianas to N. Argentina
Habitat Forest
Size Body: 4-5 in (11-14 cm) Tail: 1 1/4-2 1/2 in (4.5-6.5 cm)
Although the short-tailed opossum lives in forested country, it is a poor climber and tends to stay on the forest floor. During the day it shelters in a leafy nest, which it builds in a hollow log or tree trunk. It emerges at night to feed on seeds, shoots and fruit, as well as on insects, carrion and some small rodents, which it kills with a powerful bite to the back of the head.
Litters of up to 14 young are born at any time of year and cling to their mother's nipples and the surrounding fur, since she has no pouch. When they are older, they ride on her back.
ORDER PAUCITUBERCULATA
Caenolestidae: Shrew Opossum Family
There are only 7 known species of shrew opossum, which belong to the only family in this order. All live in inaccessible forest and grassland regions of the High Andes. None is common, and the family is poorly known. Shrew opossums are small, shrewlike animals, with thin limbs, a long, pointed snout and slender, hairy tail. Their eyes are small, and they seem to spend much of their lives in underground burrows and on surface runways. It is likely that there are more species yet to be discovered.
Shrew Opossum Caenolestes obscurus
Range Colombia, Venezuela
Habitat Montane forest
Size Body: 3 1/2-5 in (9-13 cm) Tail: 3 1/2-4 3/4 (9-12 cm)
The shrew opossum lives on the forest floor and shelters in hollow logs or underground chambers during the day. At dusk, it emerges to forage around in the surface litter for small invertebrate animals and fruit.
Shrew opossums may be far more common than is generally thought, but their inhospitable habitat makes studying them difficult. Nothing is known of their reproductive habits.
ORDER MICROBIOTHERA
Microbiotheriidae: Colocolo Family
There is a single family in this order, and a single species in this family, which appears to be closely related to the opossums.
Colocolo Dromiciops gliroides VU
Range Chile, W. Argentina
Habitat Forest
Size Body: 4 1/4-5 in (11-12.5 cm) Tail: 3 1/2-4 in (9-10 cm)
The colocolo occurs in high-altitude and lowland forest, especially in areas where Chilean Bamboo grows. It feeds mainly on insects and other invertebrates, but may also eat vegetation. It makes nests using bamboo leaves. In the colder parts of the range, colocolos hibernate in winter, but in more temperate regions, they remain active all year round.
Colocolos breed in spring. Litters contain up to 5 young which cling to the mother's fur, because there is no true pouch.
DASYURID MARSUPIALS
ORDER DASYUROMORPHA
This order includes two families of carnivorous and insectivorous marsupials that are found in Australia, Tasmania, and New Guinea.
Dasyuridae: Dasyurid Marsupial Family
This family of approximately 58 species contains a wide variety of marsupials, from tiny mouse-sized creatures, which live on the forest floor, to large, aggressive predators. Many zoologists regard it as the least advanced family of Australian marsupials because all members have fully separated digits -- fused digits are a characteristic of advanced families of marsupials. Yet its success is undoubted, for representatives are found in all habitats, from desert to tropical rain forest.
Most of the dasyurids have poorly developed pouches and resort to carrying their small, underdeveloped young about underneath them, either clinging to the mother's fur or dangling from her teats like bunches of grapes. Unlike the American opossums, which carry older young on their backs, the dasyurids deposit their offspring in nests when they become too large to carry around with them.
Pygmy Planigale Planigale maculata
Range N. and E. Australic
Habitat Arid bush and scrub
Size Body: 2-2 1/2 in (5-5.5 cm) Tail: 2 1/4 in (5.5 cm)
The pygmy planigale shelters in a burrow during the day and emerges at night to search for food. Although it is smaller than a white mouse, it feeds on large insects, such as grasshoppers (which it kills by biting off the head) and small birds. In one night, a pygmy planigale may eat its own weight in food.
Little is known of the reproduction and social organization of these animals. They appear to be solitary and to give birth to up to 12 young between December and March.
Brown Antechinus Antechinus stuartii
Range E. seaboard of Australia
Habitat Forest
Size Body: 3 3/4-4 1/4 in (10-12 cm) Tail: 4-4 3/4 in (10-12 cm)
The brown antechinus is a secretive, nocturnal animal, that is common in the forests surrounding Australia's major cities. It climbs well and probably searches for insect food in Eucalyptus and Acacia trees.
Mating, which is a violent procedure in this species that can last about 5 hours, occurs in August. A litter of 6 or 7 young is born after a gestation period of 30 to 33 days. The babies cling to the nipples on the mother's belly until they become so large that they impede her movements. They are then left in an underground nest while the mother hunts for food. The offspring reach sexual maturity and breed almost a year after birth. As a result of a hormone imbalance, the males of the species can mate only once before they die.
Mulgara Dasycercus cristicauda Vu
Range C. Australia
Habitat Desert, spinifex bush
Size Body: 5-8 1/2 in (12.5-22 cm) Tail: 2 1/4-5 in (7-13 cm)
The mulgara is perfectly adapted for life in one of the world's most inhospitable, hot, dry environments. It protects itself from the extreme heat of the desert by remaining in its burrow until the heat of the day has passed. Even when it leaves its underground home it tends to stay in places that have been in shadow.
The staple diet of the mulgara consists mainly of insects, but lizards, newborn snakes and mice are also eaten. This creature never drinks. It derives all of its liquid requirements from its prey in order to preserve water its kidneys are highly developed to excrete extremely concentrated urine.
Mulgaras breed from June to September and the usual litter contains 6 or 7 young. The pouch is little more than two lateral folds of skin.
Kowari Dasyuroides bymei
Range C. Australia
Habitat Desert, grassland
Size Body: 6 1/2-7 in (16.5-18 cm) Tail: 5-5 1/2 in (13-14 cm)
The kowari lives, either singly or in small groups, in underground burrows. At night, it emerges to search among the grass tussocks for insects, lizards and various small birds.
Kowaris breed in winter, from May to October, and produce litters of 5 or 6 young after a gestation period of 32 days.
Fat-tailed Dunnart Sminthopsis crassicaudata
Range W. Australia, E. to W. Queensland, W. New South Wales and W. Victoria
Habitat Woodland, health, grassland
Size Body: 3-3 1/2 in (8-9 cm) Tail: 2 1/4-3 1/2 in (5.5-8.5 cm)
The fat-tailed dunnart stores fat in special cells at the base of its tail. In the wet season, when the food supply of insects and spiders is abundant, the dunnart builds up its fat reserves. During the dry season it lives off these reserves and its tail gradually slims. If the drought persists longer than usual, the dunnart's body temperature falls and it enters a state of torpor so that its fat reserve lasts longer.
Dunnarts start to breed when they are about 4 months old and produce litters about every 12 weeks. Courtship is aggressive and males indulge in vicious fights for females on heat.
Quoll Dasyurus viverrinus LR:nt
Range S.E. Australia and Tasmania
Habitat Forest
Size Body: 13 1/4-17-3/4 in (35-45 cm) Tail: 8 1/4-11 3/3 in (21-30 cm)
The quoll is one of 6 species of cat-sized predatory dasyurid, specialized for life as carnivores. At one time quolls were ruthlessly destroyed by poultry keepers, but they are now known to do as much good as harm, by killing rodents, rabbits and invertebrate pests and helping to maintain the ecological balance. Quolls make their homes in rock piles or in hollow logs and emerge only at night in order to search for food.
The breeding season lasts from May to August. The quoll is one of the few marsupials known in which the litter size at birth is far higher than the number that can be supported by the mother -- a phenomenon known as superfetation. Up to 18 young are born after a gestation period of about 20 days, but within 48 hours of birth 10 or more of the babies will die. The young quolls spend the early weeks of their lives in the mother's well-developed pouch and later emerge to clamber all over her, clinging to her fur as she feeds. They are weaned at 4 1/2 months.
Tasmanian Devil Sarcophilus harrisii
Range Tasmania
Habitat Dry forest
Size Body 20 1/2-31 1/2 in (52.5-80 cm) Tail: 9-11 3/4 in (23-30 cm)
This powerfully built marsupial has the reputation of being a vicious killer of sheep and as a result great numbers were once hunted by farmers. Numbers have now recovered. In fact, the Tasmanian devil is more of a scavenger of dead sheep than a killer of live ones. Its massive head and enormous jaws, resembling those of the hyena, allow it to smash through bones. Before the Tasmanian wolf became extinct, Tasmanian devils lived almost exclusively on the carcasses discarded by the wolf.
Tasmanian devils live in dens in rock piles and under tree stumps and are normally nocturnal. Sometimes, however, they emerge during the day to bask in the sun. Tasmanian devils can live for up to 8 years. They breed in the second year, producing a litter of about 4 young in early winter (May or June). The babies remain inside the mother's well-developed pouch for 15 weeks. They are weaned at about 20 weeks old.
NUMBAT, MARSUPIAL MOLE, BANDICOOTS AND WOMBATS
Myrmecobiidae: Numbat Family
The single species in this Australian family is a small marsupial, which is adapted to the ecological niche that is filled by anteaters in other parts of the world. It was formerly called the banded anteater and feeds in a similar manner to anteaters.
Numbat Myrmecobius fasciatus VU
Range S.W. Australia
Habitat forest
Size Body: 6 3/4-10 3/4 in (17.5-27.5 cm) Tail: 5-6 3/4 in (13-17 cm)
The numbat is active during the day. It feeds mainly on termites, although ants and some other small invertebrates are also eaten. Its sticky tongue, which is about 4 in (10 cm) long, is used to sweep insects into its mouth, where they are crushed by the numbat's poorly developed teeth. A captive numbat was observed to eat 10 to 20 thousand termites daily.
Between January and May, the female numbat produces a litter of 4 young. The mother has no pouch. The young cling to her nipples and she drags them around as she searches for food.
ORDER PERAMELEMORPHA
This order includes about 21 species of omnivorous marsupials which are found in Australia and New Guinea. There are two families in the order -- the bandicoots and bilby and the New Guinean bandicoots.
Peramelidae: Bandicoot Family
There are about 12 species of bandicoot, widely distributed over Australia in a range of habitats, from desert to rain forest. The family includes the Bilby or Rabbit Bandicoot. Most of the bandicoots use their strong, clawed front feet to dig for insects larvae and plant roots and tubers.
Eastern Barred Bandicoot Perameles gunii VU
Range Australia S. Victoria: Tasmania
Habitat Woodland, heathland
Size Body: 9 3/4-15 3/4 in (25-40 cm) Tail: 3-7 in (7.5-18 cm)
Like most bandicoots, the eastern barred bandicoot is a very aggressive, belligerent creature, which lives alone. The males occupy large territories and consort with females for only as long as is necessary for mating.
Primarily a nocturnal animal, it emerges from its nest at dusk to forage for earthworms and other small invertebrates. Probing deep into the soil with its long nose, the bandicoot digs eagerly when food is located.
Although the female bandicoot has 8 nipples, she seldom produces more than 4 or 5 young. The gestation period of 11 days is one of the shortest of any mammal and is followed by 8 weeks in the pouch.
Brown Bandicoot Isoodon obesulus
Range S. Australia, Queensland
Tasmania
Habitat Scrub, forest
Size Body: 11 3/4-13 3/4 in (30-33 cm) Tail: 3-7 in (7.5-18 cm)
The brown bandicoot occurs in areas of
Library of Congress subject headings for this publication: Vertebrates Encyclopedias, Juvenile, Animals Encyclopedias, Juvenile