Marsupials are any members of the mammalian infraclass Marsupialia. All extant marsupials are endemic to Australasia and the Americas. A distinctive characteristic common to these species is that most of the young are carried in a pouch. Well-known marsupials include kangaroos, koalas, opossums and Tasmanian devils; some lesser-known marsupials are the dunnarts and cuscuses. Marsupials represent the clade originating from the last common ancestor of extant metatherians. Like other mammals in the Metatheria, they give birth to undeveloped young that reside in a pouch located on their mothers’ abdomen for a certain amount of time. Close to 70% of the 334 extant species occur on the Australian continent; the remaining 100 are found in the Americas — in South America, but thirteen in Central America, one in North America, north of Mexico. The word marsupial comes from the technical term for the abdominal pouch. It, in turn, is borrowed from Latin and from the ancient Greek μάρσιππος mársippos, meaning "pouch".
Marsupials are taxonomically identified as members of the mammalian infraclass Marsupialia, first described as a family under the order Pollicata by German zoologist Johann Karl Wilhelm Illiger in his 1811 work Prodromus Systematis Mammalium et Avium. However, James Rennie, author of The Natural History of Monkeys and Lemurs, pointed out that the placement of five different groups of mammals - monkeys, tarsiers, aye-ayes and marsupials - under a single order did not appear to have a strong justification. In 1816, French zoologist George Cuvier classified all marsupials under the order Marsupialia. In 1997, researcher J. A. W. Kirsch and others accorded infraclass rank to Marsupialia. There are two primary divisions: Australian marsupials. Marsupialia is further divided as follows:† - Extinct Superorder Ameridelphia Order Didelphimorphia Family Didelphidae: opossums Order Paucituberculata Family Caenolestidae: shrew opossums Superorder Australidelphia Order Microbiotheria Family Microbiotheriidae: monito del monte Order †Yalkaparidontia Order Dasyuromorphia Family †Thylacinidae: thylacine Family Dasyuridae: antechinuses, dunnarts, Tasmanian devil, relatives Family Myrmecobiidae: numbat Order Notoryctemorphia Family Notoryctidae: marsupial moles Order Peramelemorphia Family Thylacomyidae: bilbies Family †Chaeropodidae: pig-footed bandicoots Family Peramelidae: bandicoots and allies Order Diprotodontia Suborder Vombatiformes Family Vombatidae: wombats Family Phascolarctidae: koalas Family †Diprotodontidae: Giant wombats Family †Palorchestidae: Marsupial tapirs Family †Thylacoleonidae: marsupial lions Suborder Phalangeriformes Family Acrobatidae: feathertail glider and feather-tailed possum Family Burramyidae: pygmy possums Family †Ektopodontidae: sprite possums Family Petauridae: striped possum, Leadbeater's possum, yellow-bellied glider, sugar glider, mahogany glider, squirrel glider Family Phalangeridae: brushtail possums and cuscuses Family Pseudocheiridae: ringtailed possums and relatives Family Tarsipedidae: honey possum Suborder Macropodiformes Family Macropodidae: kangaroos and relatives Family Potoroidae: potoroos, rat kangaroos, bettongs Family Hypsiprymnodontidae: musky rat-kangaroo Comprising over 300 extant species, several attempts have been made to interpret the phylogenetic relationships among the different marsupial orders.
Studies differ on whether Didelphimorphia or Paucituberculata is the sister group to all other marsupials. Though the order Microbiotheria is found in South America, morphological similarities suggest it is related to Australian marsupials. Molecular analyses in 2010 and 2011 identified Microbiotheria as the sister group to all Australian marsupials. However, the relations among the four Australidelphid orders are not as well understood; the cladogram below, depicting the relationships among the various marsupial orders, is based on a 2015 phylogenetic study. DNA evidence supports a South American origin for marsupials, with Australian marsupials arising from a single Gondwanan migration of marsupials from South America to Australia. There are many small arboreal species in each group; the term "opossum" is used to refer to American species, while similar Australian species are properly called "possums". Marsupials have the typical characteristics of mammals—e.g. Mammary glands, three middle ear bones, true hair.
There are, striking differences as well as a number of anatomical features that separate them from Eutherians. In addition to the front pouch, which contains multiple nipples for the protection and sustenance of their young, marsupials have other common structural features. Ossified patellae are absent in most modern marsupials and epipubic bones are present. Marsupials lack a gross communication between the right and left brain hemispheres; the skull has peculiarities in comparison to placental mammals. In general, the skull is small and tight. Holes are located in the front of the orbit; the cheekbone extends further to the rear. The angular extension of the lower jaw is bent toward the center. Another feature is the hard palate which, in contrast to the placental mammals' foramina, always have more openings. The
The phascogales known as wambengers, are carnivorous Australian marsupials of the family Dasyuridae. There are three species: the brush-tailed phascogale, the red-tailed phascogale, the northern brush-tailed phascogale; as with a number of dasyurid species, the males live for only one year, dying after a period of frenzied mating. The term Phascogale was coined in 1824 by Coenraad Jacob Temminck in reference to the brush-tailed phascogale, means "pouched weasel". All three species are listed as either Near Threatened or Vulnerable by the IUCN; the following is a phylogenetic tree based on mitochondrial genome sequences: Mating happens between May and July. All males die soon after mating. Females give birth to about 6 young ones about 30 days after mating. Phascogales do not have the true pouch, found in most other marsupials. Instead, they form temporary folds of skin - sometimes called a "pseudo-pouch" around the mammary glands during pregnancy. Young stay in this pseudo-pouch area, nursing for about 7 weeks before being moved to a nest where they stay until they are weaned at about 20 weeks of age.
Females live for about 3 years, produce one litter. Groves, C. P.. Wilson, D. E.. M. eds. Mammal Species of the World: A Taxonomic and Geographic Reference. Baltimore: Johns Hopkins University Press. Pp. 31–32. ISBN 0-801-88221-4. OCLC 62265494. • Brush-tailed Phascogale fact sheet:. Also: • Red-tailed Phascogale fact sheet:. Also
Quolls are carnivorous marsupials native to mainland Australia, New Guinea, Tasmania. They are nocturnal and spend most of the day in a den. Of the six species of quoll, four are found in two in New Guinea. Another two species are known from fossil remains in Pliocene and Pleistocene deposits in Queensland. Genetic evidence indicates that quolls evolved around 15 million years ago in the Miocene, that the ancestors of the six species had all diverged by around four million years ago; the six species vary from 300 g to 7 kg. They have pink noses, they are solitary, but come together for a few social interactions such as mating which occurs during the winter season. A female gives birth to up to 18 pups, of which only six survive because she only has six teats to feed with. Quolls eat smaller mammals, small birds and insects, their natural lifespan is between five years. All species have drastically declined in numbers since Australasia was colonised by Europeans, with one species, the eastern quoll, becoming extinct on the Australian mainland, now found only in Tasmania.
Major threats to their survival include the cane toad, predators such as feral cats and foxes, urban development, poison baiting. Conservation efforts include breeding programs in captivity, one of, taking place in Tasmania with support from Rewilding Australia and Conjour; the name Dasyurus means "hairy-tail", was coined by Étienne Geoffroy Saint-Hilaire in 1796. In 1770, Captain Cook collected quolls on his exploration of the east coast of Australia, adopting the Aboriginal name for the animals. Although the origin of Cook's specimens are unclear, the word and its variants je-quoll, jaquol or taquol are derived from the language of the Guugu Yimithirr people of far north Queensland. No evidence indicates, they were likened in appearance to a polecat or marten in the earliest reports, the tiger quoll being called "spotted marten" and eastern quoll "spotted opossum", but by 1804, the names "native cat" and "tiger cat" had been adopted by early settlers. In the 1960s, noted naturalist David Fleay pushed for the revival of the term "quoll" to replace the then-current vernacular names that he felt were misleading.
They are well known animals in Australia. Four species have been recovered from Pleistocene cave deposits from Mount Etna Caves National Park near Rockhampton in central Queensland. Remains of the tiger quoll and the northern quoll, a species either identical or similar to the eastern quoll, as well as a prehistoric species as yet undescribed, all lived in what was a rainforest climate; the northern quoll is still found in the region. The fossil species D. dunmalli, described by Bartholomai in 1971, is the oldest species recovered to date. Its remains were found in Pliocene deposits near Chinchilla in southeastern Queensland. Known only from a lower jaw and some teeth, it was a relative of the tiger quoll; the first species described, the eastern quoll, was placed in the American opossum genus Didelphis by an anonymous author, named Didelphis maculata. This name is no longer considered valid, the second part of the name is now given to a different species, the tiger quoll, Dasyurus maculatus, while the eastern quoll was renamed Dasyurus viverrinus by George Shaw in 1800.
The tribe Dasyurini, to which quolls belong includes the Tasmanian devil, the antechinus, the kowari, the mulgara. Genetic analysis of cytochrome b DNA and 12S rRNA of the mitochondria indicates the quolls evolved and diversified in the late Miocene between 15 and 5 million years ago, a time of great diversification in marsupials; the ancestors of all current species had diverged by the early Pliocene, around 4 million years ago. The genus Dasyurus consists of six species of quoll: The bronze quoll is the only mammal found in the Trans Fly ecoregion, but not in northern Australia, it is found in the southern part of New Guinea south of the Fly River. Rising sea levels due to an increase in global temperature caused a land bridge that once connected Australia and New Guinea to be covered up with water. A 2007 study conducted by the University of New South Wales suggests the bronze quoll is related to the western quoll, their ancestors diverging with the separation of land masses; the western quoll or chuditch is restricted to the Jarrah Forest and the central and southern Australian Wheatbelt.
The western quoll is believed to have once occupied 70% of Australia, but because of cane toads, habitat destruction, poison baiting, it is now less abundant. The New Guinean quoll is found throughout most of New Guinea, it tends to live at an elevation of about 1,000 m, is not found in the south-western lowlands, although it can found on Yapen Island. The eastern quoll is now considered extinct on mainland Australia, it can be found near farms. The eastern quoll can be seen in the Mount Field National Park; the tiger quoll or spotted tail quoll, lives in south-eastern Australia. It tends to prefer rock dens more than dens made out of wood. In a study submitted by Belcher and Darrant in 2006, the habitats of tiger quoll were directly related to the amount of prey found in the area. Gullies and drainage ditches were used quite by the quolls, ridges with rocky outcrops were used to make the rock dens the animals enjoy; the spe
The Tasmanian devil is a carnivorous marsupial of the family Dasyuridae. It was once native to mainland Australia and is now found in the wild only on the island state of Tasmania, including tiny east-coast Maria Island where there is a conservation project with disease-free animals; the size of a small dog, the Tasmanian devil became the largest carnivorous marsupial in the world following the extinction of the thylacine in 1936. It is distantly related to the thylacine, it is characterised by its stocky and muscular build, black fur, pungent odour loud and disturbing screech, keen sense of smell, ferocity when feeding. The Tasmanian devil's large head and neck allow it to generate among the strongest bites per unit body mass of any extant mammal land predator, it hunts prey and scavenges carrion as well as eating household products if humans are living nearby. Although it is solitary, it sometimes eats with other devils and defecates in a communal location. Unlike most other dasyurids, the devil thermoregulates and is active during the middle of the day without overheating.
Despite its rotund appearance, the devil is capable of surprising speed and endurance, can climb trees and swim across rivers. It is believed that ancient marsupials migrated from what is now South America to Australia tens of millions of years ago during the time of Gondwana, that they evolved as Australia became more arid. Fossils of species similar to modern devils have been found, but it is not known whether they were ancestors of the contemporary species, or whether the current devils co-existed with these species; the date that the Tasmanian devil became locally extinct from the Australian mainland is unclear. A tooth found in Augusta, Western Australia has been dated to 430 years ago, but archaeologist Oliver Brown disputes this and considers the devil's mainland extinction to have occurred around 3000 years ago; this disappearance is blamed on dingoes, which are absent from Tasmania. Because they were seen as a threat to livestock and animals that humans hunted for fur in Tasmania, devils were hunted and became endangered.
In 1941, the devils, which were seen as implacably vicious, became protected. Since scientists have contended that earlier concerns that the devils were the most significant threat to livestock were overestimated and misplaced. Devils are not monogamous, their reproductive process is robust and competitive. Males fight one another for the females, guard their partners to prevent female infidelity. Females can ovulate three times in as many weeks during the mating season, 80% of two-year-old females are seen to be pregnant during the annual mating season. Females average four breeding seasons in their life and give birth to 20–30 live young after three weeks' gestation; the newborn lack fur, have indistinct facial features and weigh around 0.20 g at birth. As there are only four nipples in the pouch, competition is fierce and few newborns survive; the young grow and are ejected from the pouch after around 100 days, weighing 200 g. The young become independent after around nine months, so the female spends most of her year in activities related to birth and rearing.
Since the late 1990s, the devil facial tumour disease has drastically reduced the devil population and now threatens the survival of the species, which in 2008 was declared to be endangered. Programs are being undertaken by the Government of Tasmania to reduce the impact of the disease, including an initiative to build up a group of healthy devils in captivity, isolated from the disease. While the thylacine was extant it preyed on the devil, which targeted young and unattended thylacine cubs in their dens. Localised populations of devils have been reduced by collisions with motor vehicles when they are eating roadkill; the devil is an iconic symbol of Tasmania and many organisations and products associated with the state use the animal in their logos. It is seen as an important attractor of tourists to Tasmania and has come to worldwide attention through the Looney Tunes character of the same name. Starting in 2013, Tasmanian devils are again being sent to zoos around the world as part of the Australian government's Save the Tasmanian Devil Program.
Believing it to be a type of opossum, naturalist George Harris wrote the first published description of the Tasmanian devil in 1807, naming it Didelphis ursina, due to its bearlike characteristics such as the round ear. He had earlier made a presentation on the topic at the Zoological Society of London. However, that particular binomial name had been given to the common wombat by George Shaw in 1800, was hence unavailable. In 1838, a specimen was named Dasyurus laniarius by Richard Owen, but by 1877 he had relegated it to Sarcophilus; the modern Tasmanian devil was named Sarcophilus harrisii by French naturalist Pierre Boitard in 1841. A revision of the devil's taxonomy, published in 1987, attempted to change the species name to Sarcophilus laniarius based on mainland fossil records of only a few animals. However, this was not accepted by the taxonomic community at large. "Beelzebub's pup" was an early vernacular name given to it by the explorers of Tasmania, in reference to a religious figure, a prince of hell and an assistant of Satan.
Related names that were used in the 19th century were
Echidnas, sometimes known as spiny anteaters, belong to the family Tachyglossidae in the monotreme order of egg-laying mammals. The four extant species, together with the platypus, are the only surviving members of the order Monotremata, are the only living mammals that lay eggs; the diet of some species consists of ants and termites, but they are not related to the true anteaters of the Americas. Echidnas live in New Guinea. Echidnas evolved between 50 million years ago, descending from a platypus-like monotreme; this ancestor was aquatic. The echidnas are named after Echidna, a creature from Greek mythology, half-woman, half-snake, as the animal was perceived to have qualities of both mammals and reptiles. Echidnas are medium-sized, solitary mammals spines. Superficially, they resemble the anteaters of South America and other spiny mammals such as hedgehogs and porcupines, they are black or brown in colour. There have been several reports of albino echidnas, their eyes pink and their spines white.
They have slender snouts that function as both mouth and nose. Like the platypus, they are equipped with electrosensors, but while the platypus has 40,000 electroreceptors on its bill, the long-beaked echidna has only 2,000 electroreceptors, the short-beaked echidna, which lives in a drier environment, has no more than 400 located at the tip of its snout, they have short, strong limbs with large claws, are powerful diggers. Their claws on their hind limbs are curved backwards to help aid in digging. Echidnas have tiny toothless jaws; the echidna feeds by tearing open soft logs and the like, using its long, sticky tongue, which protrudes from its snout, to collect prey. The ears are slits on the sides of their heads that are unseen, as they are blanketed by their spines; the external ear is created by a large cartilaginous funnel, deep in the muscle. At 33 °C, the echidna possess the second lowest active body temperature of all mammals, behind the platypus; the short-beaked echidna's diet consists of ants and termites, while the Zaglossus species eat worms and insect larvae.
The tongues of long-beaked echidnas have tiny spines that help them capture their prey. They have no teeth, break down their food by grinding it between the bottoms of their mouths and their tongues. Echidnas' faeces are cylindrical in shape. Echidnas do not tolerate extreme temperatures. Echidnas are found in woodlands, hiding under vegetation, roots or piles of debris, they sometimes use the burrows of animals such as wombats. Individual echidnas have mutually overlapping territories. Despite their appearance, echidnas are capable swimmers; when swimming, they expose their snout and some of their spines, are known to journey to water in order to groom and bathe themselves. Echidnas and the platypus are the only egg-laying mammals, known as monotremes; the average lifespan of an echidna in the wild is estimated around 14–16 years. When grown, a female can weigh up to 4.5 kilograms and a male can weigh up to 6 kilograms. The echidnas' sex can be inferred from their size; the reproductive organs differ, but both sexes have a single opening called a cloaca, which they use to urinate, release their faeces and to mate.
Male echidnas have non-venomous spurs on the hind feet. The neocortex makes up half compared to 80 % of a human brain. Due to their low metabolism and accompanying stress resistance, echidnas are long-lived for their size. Contrary to previous research, the echidna does enter REM sleep, but only when the ambient temperature is around 25 °C. At temperatures of 15 °C and 28 °C, REM sleep is suppressed; the female lays a single soft-shelled, leathery egg 22 days after mating, deposits it directly into her pouch. An egg is about 1.4 centimetres long. While hatching, the baby echidna opens the leather shell with a reptile-like egg tooth. Hatching takes place after 10 days of gestation; the mother digs a nursery burrow and deposits the young, returning every five days to suckle it until it is weaned at seven months. Puggles will stay within their mother's den for up to a year before leaving. Male echidnas have a four-headed penis. During mating, the heads on one side "shut down" and do not grow in size.
Each time it copulates, it alternates heads in sets of two. When not in use, the penis is retracted inside a preputial sac in the cloaca; the male echidna's penis is 7 centimetres long when erect, its shaft is covered with penile spines. These may be used to induce ovulation in the female, it is a challenge to study the echidna in its natural habitat and they show no interest in mating while in captivity. Therefore, no one has seen an echidna ejaculate. There have been previous attempts, trying to force the echidna to ejaculate through the use of electrically stimulated ejaculation in order to obtain semen samples but has on
Australian Broadcasting Corporation
The Australian Broadcasting Corporation is Australia's national broadcaster founded in 1929. It is principally funded by direct grants from the Australian government, but is expressly independent of government and partisan politics; the ABC plays a leading role in journalistic independence and is fundamental in the history of broadcasting in Australia. Modelled on the BBC in the United Kingdom, it was financed by consumer licence fees on broadcasting receivers. Licence fees were abolished in 1973 and replaced principally by direct government grants, as well as revenue from commercial activities related to its core broadcasting mission; the ABC now provides television, radio and mobile services throughout metropolitan and regional Australia and overseas through ABC Australia and Radio Australia. The ABC headquarters is in an inner-city suburb of Sydney, New South Wales. Founded in 1929 as the Australian Broadcasting Company, the ABC was a Government licensed consortium of private entertainment and content providers, authorised under supervision to broadcast on the airwaves using a two-tiered system.
The "A" system derived its funds from the licence fees levied on the purchasers of the radio receivers, with an emphasis on building the radio wave infrastructure into regional and remote areas, whilst the "B" system relied on privateers and their capacity to establish viable enterprises using the new technology. Following the general downward economic trends of the era, as entrepreneurial ventures in National infrastructure struggled with viability, the "Company" was subsequently acquired to become a state-owned corporation on 1 July 1932 and renamed as Australian Broadcasting Commission, re-aligning more to the British, BBC model; the Australian Broadcasting Corporation Act 1983 changed the name of the organisation to the Australian Broadcasting Corporation, effective 1 July 1983. Although funded and owned by the government, the ABC remains editorially independent as ensured through the Australian Broadcasting Corporation Act 1983; the ABC is sometimes informally referred to as "Aunty" in imitation of the British Broadcasting Corporation's nickname.
The first public radio station in Australia opened in Sydney on 23 November 1923 under the call sign 2SB with other stations in Melbourne, Adelaide and Hobart following. A licensing scheme, administered by the Postmaster-General's Department, was soon established allowing certain stations government funding, albeit with restrictions placed on their advertising content. Following a 1927 royal commission inquiry into radio licensing issues, the government established the National Broadcasting Service which subsequently took over a number of the larger funded stations, it nationalised the Australian Broadcasting Company, created by entertainment interests to supply programs to various radio stations. On 1 July 1932, the Australian Broadcasting Commission was established, taking over the operations of the National Broadcasting Service and establishing offices in each of Australia's capital cities. Over the next four years the stations were reformed into a cohesive broadcasting organisation through regular program relays, coordinated by a centralised bureaucracy.
The Australian broadcast radio spectrum was constituted of the commercial sector. News broadcasts were restricted, due to pressure from Sir Keith Murdoch, who controlled many Australian newspapers. However, journalists such as Frank Dixon and John Hinde began to subvert the agreements in the late 1930s. In 1939, Warren Denning was appointed to Canberra as the first ABC political correspondent, after Murdoch had refused to allow his newspapers to cover a speech by Joseph Lyons. In 1942 The Australian Broadcasting Act was passed, giving the ABC the power to decide when, in what circumstances, political speeches should be broadcast. Directions from the Minister about whether or not to broadcast any matter now had to be made in writing, any exercise of the power had to be mentioned in the Commission's Annual Report, it was used only once, in 1963. In the same year, "Kindergarten of the Air" began on ABC Radio in Perth, was broadcast nationally. In 1944 18-year-old Patricia Delaney, of Sydney, was the Australian Broadcasting Corporation's only girl cadet announcer, the youngest member of announcing staff.
Australian Broadcasting Corporation, 1920-1949 The ABC commenced television broadcasting in 1956, followed the earlier radio practice of naming the station after the first letter of the base state. ABN-2 Sydney was inaugurated by Prime Minister Robert Menzies on 5 November 1956, with the first broadcast presented by Michael Charlton, James Dibble reading the first television news bulletin. ABV-2 followed two weeks on 18 November 1956. Stations in other capital cities followed: ABQ-2, ABS-2, ABW-2, ABT-2. ABC-3 Canberra opened in 1961, ABD-6 started broadcasting in 1971, both named after the base city. Although radio programs could be distributed nationally by landline, television relay facilities were not in place until the early 1960s; this meant that news bulletins had to be sent to each capital city by teleprinter, to be prepared and presented separately in each city, with filmed materials copied manually and sent to each state. Other television programs at the time included the popular Six O'Clock Rock hosted by Johnny O'Keefe, Mr. Squiggle, as well as operas and plays.
In 1973 New South Wales Rugby League boss Kevin Humphreys negotiated rugby league's first television deal with the ABC. In 1975, colour television was
Wombats are short-legged, muscular quadrupedal marsupials that are native to Australia. They are about 1 m in length with stubby tails. There are three extant species and they are all members of the family Vombatidae, they are adaptable and habitat tolerant, are found in forested and heathland areas of south-eastern Australia, including Tasmania, as well as an isolated patch of about 300 ha in Epping Forest National Park in central Queensland. Though genetic studies of the Vombatidae have been undertaken, evolution of the family is not well understood. Wombats are estimated to have diverged from other Australian marsupials early, as long as 40 million years ago, while some estimates place divergence at around 25 million years. While some theories place wombats as miniaturised relatives of diprotodonts, such as the rhinoceros-sized Diprotodon, more recent studies place the Vombatiformes as having a distinct parallel evolution, hence their current classification as a separate family. Wombats dig extensive burrow systems with powerful claws.
One distinctive adaptation of wombats is their backward pouch. The advantage of a backward-facing pouch is that when digging, the wombat does not gather soil in its pouch over its young. Although crepuscular and nocturnal, wombats may venture out to feed on cool or overcast days, they are not seen, but leave ample evidence of their passage, treating fences as minor inconveniences to be gone through or under, leaving distinctive cubic feces. As wombats arrange these feces to mark territories and attract mates, it is believed that the cubic shape makes them more stackable and less to roll, which gives this shape a biological advantage; the method by which the wombat produces them is not well understood, but it is believed that the wombat intestine stretches preferentially at the walls. The adult wombat produces between 80 and 100, two-centimetre pieces of feces in a single night, four to eight pieces each bowel movement. Wombats are herbivores, their incisor teeth somewhat resemble those of rodents, being adapted for gnawing tough vegetation.
Like many other herbivorous mammals, they have a large diastema between their incisors and the cheek teeth, which are simple. The dental formula of wombats is 126.96.36.199.0.1.4 × 2 = 24. Wombats' fur can vary from a sandy colour from grey to black. All three known extant species weigh between 20 and 35 kg. Female wombats give birth to a single young in the spring, after a gestation period, which like all marsupials can vary, in the case of the wombat: 20–21 days, they have well-developed pouches. Wombats are weaned after 15 months, are sexually mature at 18 months. A group of wombats is known as a mob, or a colony. Wombats live up to 15 years in the wild, but can live past 20 and 30 years in captivity; the longest-lived captive wombat lived to 34 years of age. Wombats have an extraordinarily slow metabolism, taking around eight to 14 days to complete digestion, which aids their survival in arid conditions, they move slowly. When threatened, they can reach up to 40 km/h and maintain that speed for up to 90 seconds.
Wombats defend home territories centred on their burrows, they react aggressively to intruders. The common wombat occupies a range of up to 23 ha, while the hairy-nosed species have much smaller ranges, of no more than 4 ha. Dingos and Tasmanian devils prey on wombats. Extinct predators were to have included Thylacoleo and the thylacine, their primary defence is their toughened rear hide, with most of the posterior made of cartilage. This, combined with its lack of a meaningful tail, makes it difficult for any predator that follows the wombat into its tunnel to bite and injure its target; when attacked, wombats dive into a nearby tunnel. A wombat may allow an intruder to force its head over the wombat's back, use its powerful legs to crush the skull of the predator against the roof of the tunnel, or drive it off with two-legged kicks, like those of a donkey. Wombats are quiet animals. Bare-nosed wombats can make a number of more than the Hairy-nosed wombats. Wombats tend to be more vocal during mating season.
When angered, they can make hissing sounds. Their call sounds somewhat like a pig's squeal, they can make grunting noises, a low growl, a hoarse cough, a clicking noise. The three extant species of wombat all are endemic to a few offshore islands, they are protected under Australian law. Common wombat Northern hairy-nosed wombat or yaminon Southern hairy-nosed wombat Depiction of the animals in rock art are exceptionally rare, though examples estimated to be up to 4,000 years old have been discovered in the Wollemi National Park; the wombat is depicted in aboriginal Dreamtime as an animal of little worth. The mainland stories tell of the wombat as originating from a person named Warreen whose head had been flattened by a stone and tail amputated as punishment for selfishness. In contrast, the Tasmanian aboriginal story first recorded in 1830 tells of the wombat the great spirit Moihernee had asked hunters to leave alone. In both cases, the wombat is regarded as having been banished to its burrowing habitat.
Estimates of wombat distribution prior to European settlement are that numbers of all three surviving species were prolific and that they