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The koala instinctively seeks refuge in the higher branches, where it is vulnerable to intense heat and flames. Bushfires also fragment the animal's habitat, which restricts their movement and leads to population decline and loss of genetic diversity.[94] Dehydration and overheating can also prove fatal.[95] Consequently, IBM ThinkPad T40 2678 CPU Fan

the koala is vulnerable to the effects of climate change. Models of climate change in Australia predict warmer and drier climates, suggesting that the koala's range will shrink in the east and south to more mesic habitats.[96] Droughts also affect the koala's well-being. For example, a severe drought in 1980 caused many Eucalyptus trees to lose their leaves. IBM Thinkpad T43 CPU Fan

Subsequently, 63% of the population in southwestern Queensland died, especially young animals that were excluded from prime feeding sites by older, dominant koalas, and recovery of the population was slow.[39] Later, this population declined from an estimated mean population of 59,000 in 1995 to 11,600 in 2009, IBM ThinkPad T43 2668 CPU Fan

a reduction attributed largely to hotter and drier conditions resulting from droughts in most years between 2002 and 2007.[97] Another predicted negative outcome of climate change is the effect of elevations in atmospheric CO2 levels on the koala's food supply: increases in CO2 cause Eucalyptus trees to reduce protein and increase tannin concentrations in their leaves, reducing the quality of the food source. IBM ThinkPad T43 1871 CPU Fan

 

The first written reference of the koala was recorded by John Price, servant of John Hunter, the Governor of New South Wales. Price encountered the "cullawine" on 26 January 1798, during an expedition to the Blue Mountains,[99] although his account was not published until nearly a century later in Historical Records of Australia.[100] ACER Travelmate 8104WLMI CPU Fan

In 1802, French-born explorer Francis Louis Barrallier encountered the animal when his two Aboriginal guides, returning from a hunt, brought back two koala feet they were intending to eat. Barrallier preserved the appendages and sent them and his notes to Hunter's successor, Philip Gidley King, who forwarded them to Joseph Banks. DELL Latitude E4300 CPU Fan

Similar to Price, Barrallier's notes did not get published until 1897.[101] Reports of the "Koolah" appeared in the Sydney Gazette in late 1803, and helped provide the impetus for King to commission the artist John Lewin to paint watercolours of the animal. Lewin painted three pictures, ASUS F80S CPU Fan

one of which was subsequently made into a print that was reproduced inGeorge Culver's The Animal Kingdom (first published in 1827) and several European works on natural history.[102]

Botanist Robert Brown was the first to write a detailed scientific description of the koala in 1814, HP Pavilion dv5-1058eo CPU Fan

based on a female specimen captured near what is now Mount Kembla in the Illawarra region of New South Wales. Austrian botanical illustrator Ferdinand Bauerdrew the animal's skull, throat, feet and paws. Brown's work remained unpublished and largely unnoticed, however, as his field books and notes remained in his possession until his death, IBM 13N5182 CPU Fan

when they were bequeathed to the British Museum of Natural History. They were not identified until 1994, while Bauer's koala watercolours were not published until 1989.[103] British surgeon Everard Home included details of the koala based on eyewitness accounts of William Paterson, who had befriended Brown and Bauer during their stay in New South Wales.[104] IBM Thinkpad T30 2366-AA3 CPU Fan

Home, who in 1808 published his report in the journal Philosophical Transactions of the Royal Society,[105] gave the animal the scientific name Didelphis coola.[106]

The first published image of the koala appeared in George Perry's (1810) natural history work Arcana.[107] IBM Thinkpad T30 CPU Fan

Perry called it the "New Holland Sloth" on account of its perceived similarities to the Central and South American tree-living mammals of genus Bradypus. His disdain for the koala, evident in his description of the animal, was typical of the prevailing early 19th-century British attitude about the primitiveness and oddity of Australian fauna: HP 535438-001 CPU Fan

the eye is placed like that of the Sloth, very close to the mouth and nose, which gives it a clumsy awkward appearance, and void of elegance in the combination ... they have little either in their character or appearance to interest the Naturalist or Philosopher. As Nature however provides nothing in vain, DELL Inspiron N3010 CPU Fan

we may suppose that even these torpid, senseless creatures are wisely intended to fill up one of the great links of the chain of animated nature ...".

Naturalist and popular artist John Gould illustrated and described the koala in his three-volume work The Mammals of Australia(1845–63) and introduced the species, HP Pavilion dv6-3070tx CPU Fan

as well as other members of Australia's little-known faunal community, to the general British public.[110] Comparative anatomist Richard Owen, in a series of publications on the physiology and anatomy of Australian mammals, presented a paper on the anatomy of the koala to the Zoological Society of London.[111] IBM 41W5269 CPU Fan

In this widely cited publication he provided the first careful description of its internal anatomy, and noted its general structural similarity to the wombat.[112] English naturalist George Robert Waterhouse, curator of the Zoological Society of London, was the first to correctly classify the koala as a marsupial in the 1840s. ASUS A8H CPU Fan

He identified similarities between it and its fossil relatives Diprotodon and Nototherium, which had been discovered just a few years before.[113] Similarly, Gerard Krefft, curator of the Australian Museum, noted evolutionary mechanisms at work when comparing the koala to its ancestral relatives in his 1871 The Mammals of Australia.[114] SONY UDQFRZH13CF0 CPU Fan

 

The first living koala in Britain arrived in 1881, purchased by the Zoological Society of London. As related by prosecutor to the society, William Alexander Forbes, the animal suffered an accidental demise when the heavy lid of a washstand fell on it and it was unable to free itself. Forbes used the opportunity to dissect the fresh female specimen, HP COMPAQ 2510P CPU Fan

and thus was able to provide explicit anatomical details on the female reproductive system, the brain, and the liver—parts not previously described by Owen, who had access only to preserved specimens.[115] Scottish embryologist William Caldwell—well known in scientific circles for determining the reproductive mechanism of the platypus—described the uterine development of the koala in 1884,[ APPLE 661-4951 CPU Fan

and used the new information to convincingly place the koala and the monotremes into an evolutionary time frame.[117]

Prince Henry, Duke of Gloucester, visited the Koala Park Sanctuary in Sydney in 1934[118] and was "intensely interested in the bears". HP Pavilion dv6-3034ca CPU Fan

His photograph, with Noel Burnet, the founder of the park, and a koala, appeared in the Sydney Morning Herald. After World War II, when tourism to Australia increased and the animals were exported to zoos overseas, the koala's international popularity rose. Several political leaders and members of royal families had their pictures taken with koalas, HP G56-126NR CPU Fan

including Queen Elizabeth II, Prince Harry, Crown Prince Naruhito, Crown Princess Masako, Pope John Paul II, US President Bill Clinton, Soviet premier Mikhail Gorbachev and South African President Nelson Mandela.

The koala is well known worldwide and is a major draw for Australian zoos and wildlife parks. Compaq Presario C556CA CPU Fan

It has been featured in advertisements, games, cartoons and as soft toys.[120] It benefited the Australian tourism industry by over an estimated billion dollars in 1998, a figure that has since grown.[121] In 1997, half of visitors to Australia, especially those from Korea, Japan, and Taiwan, sought out zoos and wildlife parks; SONY Vaio VGN-NR360E CPU Fan

about 75 percent of European and Japanese tourists placed the koala at the top of their list of animals to see.[122] According to biologist Stephen Jackson: "If you were to take a straw poll of the animal most closely associated with Australia, it's a fair bet that the koala would come out marginally in front of the kangaroo".[120] HP Pavilion dv5170us CPU Fan

Factors that contribute to the koala's enduring popularity include its childlike body proportions and teddy bear-like face.[123] Such affection for the species is reflected in a stand-up routine by comedian Mitch Hedberg, who stated, "My apartment is infested with koala bears. It's the cutest infestation ever. Way better than cockroaches".[124] SONY Vaio VPC-EE3WFX/WI CPU Fan

 

The koala is featured in the Dreamtime stories and mythology of indigenous Australians. The Tharawal people believed that the animal helped row the boat that brought them to the continent.[125] Another myth tells of how a tribe killed a koala and used its long intestines to create a bridge for people from other parts of the world. HP G56-126NR CPU Fan

This narrative highlights the koala's status as a game animal and the length of its intestines.[126] Several stories tell of how the koala lost its tail. In one, a kangaroo cuts it off to punish the koala for being lazy and greedy.[127] Tribes in both Queensland and Victoria regarded the koala as a wise animal and sought its advice. HP 3MLX8TATP20 CPU Fan

Bidjara-speaking people credited the koala for turning barren lands into lush forests.[128] The animal is also depicted in rock carvings, though not as much as some other species.[129]

Early European settlers in Australia considered the koala to be a prowling sloth-like animal with a "fierce and menacing look".[130SONY Vaio VGN-NW240F/S CPU Fan

] At the beginning of the 20th century, the koala's reputation took a more positive turn, largely due to its growing popularity and depiction in several widely circulated children's stories.[131] It is featured in Ethel Pedley's 1899 book Dot and the Kangaroo, in which it is portrayed as the "funny native bear".[130] SONY Vaio VPC-EB1Z0E/B CPU Fan

Artist Norman Lindsaydepicted a more anthropomorphic koala in The Bulletin cartoons, starting in 1904. This character also appeared as Bunyip Bluegum in Lindsay's 1918 book The Magic Pudding.[132] Perhaps the most famous fictional koala is Blinky Bill. Created by Dorothy Wall in 1933, the character appeared in several books and has been the subject of films, Compaq Presario CQ60-514NR CPU Fan

TV series, merchandise and a 1986 environmental song by John Williamson.[133] The first Australian stamp featuring a koala was issued by the Commonwealth in 1930.[134] A television ad campaign for Australia's national airline Qantas, starting in 1967 and running for several decades, featured a live koala (voiced by Howard Morris), who complained that too many tourists were coming to Australia and concluded "I hate Qantas".[135] Toshiba Satellite X205-S9800 CPU Fan

The series has been ranked among the greatest commercials of all time.[136]

The song "Ode to a Koala Bear" appears on the B-side of the 1983 Paul McCartney/Michael Jackson duet album Say Say Say.[133] A koala is the main character inHanna-Barbera's The Kwicky Koala Show and Nippon Animation's NoozlesASUS G2P CPU Fan

both of which were animated cartoons of the early 1980s. Food products shaped like the koala include the Caramello Koala chocolate bar and the bite-sized cookie snack Koala's March. Dadswells Bridge in Victoria features a tourist complex shaped like a giant koala,[119] and the Queensland Reds rugby team has a koala as its mascot.[137] The Platinum Koala coin features the animal on the reverse and Elizabeth II on the obverse. Compaq Presario CQ60-430SA CPU Fan

 

In 2008, the International Union for Conservation of Nature listed the koala under Least Concern for the following reasons: "Its wide distribution, presumed large population, and because it is unlikely to be declining at nearly the rate required to qualify for listing in a threatened category."[1] DELL BFB0505HA CPU Fan

Australian policy makers declined a 2009 proposal to include the koala in the Environment Protection and Biodiversity Conservation Act 1999.[19] In 2012, the Australian Government listed koala populations in Queensland and New South Wales as Vulnerable, because of a 40% population decline in the former and a 33% decline in the latter. HP Pavilion dv5-1272et CPU Fan

Populations in Victoria and South Australia appear to be abundant; however, the Australian Koala Foundation argues that the exclusion of Victorian populations from protective measures is based on a misconception that the total koala population is 200,000, whereas they believe it is probably less than 100,000. Toshiba AB7005HX-SB3 CPU Fan

 

Koalas were hunted for food by Aboriginals. A common technique used to capture the animals was to attach a loop of ropey bark to the end of a long, thin pole, so as to form a noose. This would be used to snare an animal high in a tree, beyond the reach of a climbing hunter; Toshiba Satellite A500-18T CPU Fan

an animal brought down this way would then be killed with a stone hand axe or hunting stick (waddy).[140] According to the customs of some tribes, it was considered taboo to skin the animal, while other tribes thought the animal's head had a special status, and saved them for burial.[141]

The koala was heavily hunted by European settlers in the early 20th century,[142] HP Pavilion dv5-2135dx CPU Fan

largely for its thick, soft fur. More than two million pelts are estimated to have left Australia by 1924. Pelts were in demand for use in rugs, coat linings, muffs, and as trimming on women's garments.[143] Extensive cullings occurred in Queensland in 1915, 1917, and again in 1919, when over one million koalas were killed with guns, poisons and nooses. ASUS EEE PC 1201NL CPU Fan

The public outcry over these cullings was probably the first wide-scale environmental issue that rallied Australians. Novelist and social critic Vance Palmer, writing in a letter to the The Courier-Mail, expressed the popular sentiment:

"The shooting of our harmless and lovable native bear is nothing less than barbarous ... SONY Vaio VGN-NW240D/T CPU Fan

No one has ever accused him of spoiling the farmer's wheat, eating the squatter's grass, or even the spreading of the prickly pear. There is no social vice that can be put down to his account ... He affords no sport to the gun-man ... And he has been almost blotted out already from some areas." Compaq Presario CQ60-418DX CPU Fan

Despite the growing movement to protect native species, the poverty brought about by the drought of 1926–28 led to the killing of another 600,000 koalas during a one-month open season in August 1927.[145] In 1934, Frederick Lewis, the Chief Inspector of Game in Victoria, said that the once abundant animal had been brought to near extinction in that state, SONY Vaio VGN-NW240D CPU Fan

suggesting that only 500–1000 remained. The first successful efforts at conserving the species were initiated by the establishment of Brisbane's Lone Pine Koala Sanctuary and Sydney's Koala Park Sanctuary in the 1920s and 1930s. The owner of the latter park, Noel Burnet, SONY VGN-BX197XP CPU Fan

became the first to successfully breed koalas and earned a reputation as the foremost contemporary authority on the marsupial.[148] In 1934, David Fleay, curator of Australian mammals at the Melbourne Zoo, established the first Australian faunal enclosure at an Australian zoo, and featured the koala. Toshiba Satellite L645D-S4056 CPU Fan

This arrangement allowed him to undertake a detailed study of its diet in captivity. Fleay later continued his conservation efforts at Healesville Sanctuary and theDavid Fleay Wildlife Park.

Since 1870, koalas have been introduced to several coastal and offshore islands, including Kangaroo Island and French Island. Toshiba AB7805HX-GB3 CPU Fan

Their numbers have significantly increased,[150] and since the islands are not large enough to sustain such high koala numbers,overbrowsing has become a problem.[151] In the 1920s, Lewis initiated a program of large-scale relocation and rehabilitation programs to transfer koalas whose habitat had become fragmented or reduced to new regions, Toshiba Satellite L500-208 CPU Fan

with the intent of eventually returning them to their former range. For example, in 1930–31, 165 koalas were translocated to Quail Island. After a period of population growth, and subsequent overbrowsing of gum trees on the island, about 1300 animals were released into mainland areas in 1944. The practice of translocating koalas became commonplace; HP 535441-001 CPU Fan

Victorian State manager Peter Menkorst estimated that from 1923 to 2006, about 25,000 animals were translocated to more than 250 release sites across Victoria.[152] Since the 1990s, government agencies have tried to control their numbers by culling, but public and international outcry has forced the use of translocation andsterilisation instead.[153] Toshiba Satellite P100-444 CPU Fan

 

One of the biggest anthropogenic threats to the koala is habitat destruction and fragmentation. In coastal areas, the main cause of this is urbanisation, while in rural areas habitat is cleared for agriculture. Native forest trees are also taken down to be made into wood products.[154] Since Europeans arrived, localised deforestation of eucalypts in Australia ranges from 33 to 93%. HP Pavilion dv7-3114eo CPU Fan

In addition, Acacia habitats, which can also support koala populations, declined by 80% overall. In 2000, Australia ranked fifth in the world by deforestation rates, having cleared 564,800 hectares (1,396,000 acres).[155] The geographical range of the koala has shrunk by more than 50% since European arrival, largely due to fragmentation of habitat in Queensland.[46] HP Mini 110-1125SA CPU Fan

The koala's "vulnerable" status in Queensland and New South Wales means that developers in these states must consider the impacts on this species when making building applications.[139] In addition, koalas live in many protected areas.[1]

While urbanisation can pose a threat to koala populations, the animals can survive in urban areas provided there are enough trees.[156] HP KSB06105HA CPU Fan

Urban populations have distinct vulnerabilities: collisions with vehicles and attacks by domestic dogs kill about 4000 animals every year.[98] Injured koalas are often taken to wildlife hospitals and rehabilitation centres.[156] In a 30-year retrospective study performed at a New South Wales koala rehabilitation centre, Compaq Presario CQ60-210eo CPU Fan

it was found that trauma (usually resulting from a motor vehicle accident or dog attack) was the most frequent cause of admission, followed by symptoms of chlamydia infection.[157] Wildlife caretakers are issued with special permits but have to release the animals back into the wild when they are either well enough or, in the case of joeys, old enough. HP Pavilion dv7-2250sf CPU Fan

As with most native animals, the koala cannot legally be kept as a pet in Australia or anywhere else.

Megaladapis, informally known as koala lemur,[1][2] is an extinct genus belonging to the family Megaladapidae, consisting of three extinct species of lemurs that once inhabited the island of Madagascar. The largest measured between 1.3 to 1.5 m (4 to 5 ft) in length. HP 434678-001 CPU Fan

 

Megaladapis was quite different from any living lemur. Its body was squat and built like that of the modern koala. Its long arms, fingers, feet, and toes were specialized for grasping trees, and its legs were splayed for vertical climbing. The hands and feet were curved and the ankles and wrists did not have the usual stability needed to travel on the ground that most other Lemurids have.[3] HP G60-230us CPU Fan

Its head was unlike any other primates, most strikingly, its eyes were on the sides of its skull, instead of forward on the skull like all other primates. Its long canine teeth and a cow-like jaw formed a tapering snout. Its jaw muscles were powerful for chewing the tough native vegetation. Its body weight reached 50 kilograms (110 lb). HP Pavilion dv6365us CPU Fan

The shape of its skull was unique among all known primates, with a nasal region which showed similarities to those of rhinoceros, what was probably a feature combined with an enlarged upper lip for grasping leaves. An endocast of the skull was taken and it was found that the brain capacity was about 250cc. This is about 3 to 4 times the size of a common cat's.[4] HP 535439-001 CPU Fan

 

Megaladapis evolved because the island's topography was always changing. Along with the other lemurs, Megaladapis specialized within its own niche. The general expectations of tree climbers such as Megaladapis is that with an increase in size, the body's forelimbs will also increase proportionally. COMPAQ 6910c CPU Fan

It is often believed that Malagasy legends of the tretretretre or tratratratra, an extinct animal, refer to Megaladapis, but the details of these tales, notably the "human-like" face of the animal, match the related Palaeopropithecus much better.

When humans arrived, between 1,500 and 2,000 years ago, IBM Lenovo IdeaPad G510 CPU Fan

the archaeological record shows that they cleared large areas of the island using "slash-and-burn" techniques. Unable to adapt to the environmental changes and the presence of humans,Megaladapis became extinct approximately 500 years ago.

Megaladapis has been found around the marsh of Ambolisatra on the southwestern HP G62-110SO CPU Fan

side of Madagascar and was one of multipleMegafauna that went extinct on Madagascar during this time period. They were also slow-moving creatures that were active during the day. This might have made them more susceptible to predators, forest fires, habitat destruction, and possibly introduced pathogens. DELL Precision M6400 CPU Fan

 

Sam (died 6 August 2009), also known as Sam the Koala, was a female koala from the forests of Mirboo North, Victoria,Australia. She became publicly known when a video and photographs of her being rescued by a firefighter were distributed on the internet and through the media during the aftermath of the Black Saturday bushfires. SONY Vaio VPC-EB290X CPU Fan

 

A mobile phone video of the event,[1] which attracted just under 1,200,000 hits on YouTube,[2] shows firefighter David Tree approaching Sam who initially attempts to flee but then stops—Tree later speculated that the koala had been thinking "I can't run, I'm weak and sore, put me out of my misery"—and Tree calls for water.[1] HP Envy 17-1090eo CPU Fan

Sam is then shown drinking from a bottle he is holding for her.[3] She is also seen allowing herself to be patted, and holding her paw on his hand. Sam became a symbol of hope.[4] It was initially thought that Sam had been rescued by Tree following theFebruary 2009 Victorian bushfires; Toshiba Satellite A210-1CF CPU Fan

however, the event actually occurred in the week before the worst of the fires, duringbackburning operations initiated by firefighters.[5] Tree and his crew came across Sam when they were blacking out[6][7]after the fires had gone through. The video was recorded by Tree and other firefighters; it had been intended for Tree's daughter. Dell Vostro 3450 CPU Fan

 

Sam was subsequently taken to the Southern Ash Wildlife Centre in Rawson[8] where she was found to be suffering fromsecond-degree burns to her paws and given painkillers.[1][9] Caretakers at the shelter expected that it would take her about eight months to recover.[1][10] Based on the condition of her teeth, the shelter manager estimated her to be between two and four years old.[1] Toshiba Satellite A10-103 CPU Fan

She was placed with a male koala named Bob,[10] who had been rescued from another of the bushfire areas two days earlier and was suffering from third-degree burns.

Sam's story was featured in media outlets worldwide, including The New York Times and CNN.[11] Gossip site TMZ.com mocked the rescue, calling Sam "pampered";[12Compaq Presario A900 CTO CPU Fan

]this drew significant reader backlash and attention. TMZ later apologised to Sam.[13]

Sam was euthanised on 6 August 2009. The decision was made after exploratory surgery on her urinary bladder and uterus to evaluate the possible removal of cystscaused by urogenital chlamydiosis. ACER Aspire 4736ZG CPU Fan

As her condition was inoperable the veterinarian stated that the decision was made to euthanise to prevent her suffering.[14]Sam's remains were moved to Melbourne Museum where they were preserved as a symbol of the bushfires.

An image of Sam with David Tree was used as cover art on a fundraising CD, Toshiba Satellite A10-103 CPU Fan

Bushfire Aid, to which 35 national and international artists donated songs. All proceeds were donated to the Salvation Army Bushfire Appeal.[17] A total of A$300,000 was also raised for the Country Fire Authority and other charities through selling photographs of Sam's rescue.[18] SONY MCF-519PAM05 CPU Fan

 

In February 2009, an application was made to register the words "Sam the Koala" as a trademark for chocolates[19] and in August 2009 media reported a dispute.

On 20 February 2009 and 13 March 2009, an application was made to register the words "Sam the Koala" as a trademark in Class 30 (for chocolates) and as a trademark in Class 16 (for colouring-in books). SONY Vaio VPC-EB290X CPU Fan

The applications were approved for Acceptance of Registration of a Trademark on 25 June 2009 and 16 July 2009 respectively. An opposition notice was lodged by DSE in September 2009 and that opposition outcome is still pending a final decision by IPAustralia. HP Pavilion dv7-2043cl CPU Fan

Media published the trademark applications which led to a dispute called an 'Opposition Notice'- IPAustralia History page [21]

On 27 July 2010 the DSE applied for a new trademark TM1374402, Sam The Koala, in Class32 (beverages), Class33 (alcoholic beverages), HP Pavilion dv7-2130ev CPU Fan

Class41 (education, training and cultural activities), Class43 (services for providing food and drink), and Class44 (veterinary services and hygienic and beauty care for animals),[22] however DSE Application TM1374402 was issued an "Adverse Report1" [23] on 27 August 2010. HP 608772-001 CPU Fan

 

Koala retrovirus (KoRV) is a retrovirus that is present in many populations of koalas. It has been implicated as the agent of Koala Immune Deficiency Syndrome (KIDS), an AIDS-like immunodeficiency that leaves infected koalas more susceptible to infectious disease and cancers. Toshiba Satellite A100-194 CPU Fan

The virus is thought to be a recently introduced exogenous virus that is also integrating into the koala genome (becoming endogenous). Thus the virus can transmit both horizontally (from animal to animal in the classic sense) andvertically (from parent to offspring as a gene). The horizontal modes of transmission are not well defined but are thought to require close contact. HP Pavilion tx1205/ CT CPU Fan

 

Koala retrovirus was initially described as a novel endogenous retrovirus found within the koala genome and in tissues as freevirions. Viral DNA sequence analysis showed intact open reading frames and pathogenic DNA motifs strongly suggesting that KoRV is an active replicating endogenous virus that can also produce infectious virions. HP Pavilion dv6640ep CPU Fan

The analysis also showed that KoRV was closely related to the highly pathogenic Gibbon Ape Leukemia Virus (GALV).[2] The epidemiology of how koalas and gibbons came to share such similar viruses remains unclear.

The virus has been attributed to 80% of deaths in captive koalas in Queensland from leukaemia, COMPAQ Presario CQ42-401TU CPU Fan

lymphoma, malignant tumours and immune deficiency disorders. In 2008, lead researcher Jon Hanger, said the virus was a threat that could lead to extinction of koalas in Queensland within 15 years, claiming 100% infection rates in studied populations that suggest an epidemic.[3]

Research has also shown that some populations of koalas, Toshiba Satellite A300D CPU Fan

particularly an isolated colony on Kangaroo Island do not appear to have the endogenous form of the retrovirus. This suggests that the virus gene sequence is a new acquisition for the koala genome. Prevalence of KoRV (and KIDS) in Australian koala populations suggests a trend spreading from the north down to the south of Australia. HP Pavilion dv8397ea CPU  Fan

Northern populations are completely infected, while some southern populations (including Kangaroo Island) are free.[4] Prior to this 'koala retrovirus' was used to refer to an unidentified oncovirus detected in cancer-affected koalas.[5]

It is thought that further studying KoRV will allow valuable insight into how endogenous retrovirus develop and incorporate themselves into mammalian genomes. HP Pavilion dv9821ea CPU Fan

 

Although most of Australia is semi-arid or desert, it includes a diverse range of habitats from alpine heaths to tropical rainforests, and is recognised as amegadiverse country. The fungi typify that diversity; the total number that occur in Australia, including those not yet discovered, has been estimated at around 250,000 species, HP COMPAQ TC4200 CPU Fan

of which roughly 5% have been described.[174] Because of the continent's great age, extremely variable weather patterns, and long-term geographic isolation, much of Australia's biota is unique and diverse. Approximately 85% of flowering plants, 84% of mammals, more than 45% of birds, and 89% of in-shore, temperate-zone fish are endemic.[175] SONY Vaio VGN-NW228F CPU Fan

Australia has the greatest number of reptiles of any country, with 755 species.

Australian forests are mostly made up of evergreen species, particularly eucalyptus trees in the less arid regions, wattlesreplace them in drier regions and deserts as the most dominant species.[177] Among well-known Australian animals are themonotremes (the platypus and echidna); HP G62-b16ST CPU Fan

a host of marsupials, including the kangaroo, koala, and wombat, and birds such as theemu and the kookaburra.[177] Australia is home to many dangerous animals including some of the most venomous snakes in the world.[178] The dingo was introduced by Austronesian people who traded with Indigenous Australians around 3000 BCE.[179] HP 580696-001 CPU Fan

Many animal and plant species became extinct soon after first human settlement,[180] including the Australian megafauna; others have disappeared since European settlement, among them the thylacine.

Many of Australia's ecoregions, and the species within those regions, are threatened by human activities and introducedanimal, HP Pavilion dv6-3049tx CPU Fan

chromistan, fungal and plant species.[183] The federal Environment Protection and Biodiversity Conservation Act 1999is the legal framework for the protection of threatened species.[184] Numerous protected areas have been created under theNational Strategy for the Conservation of Australia's Biological Diversity to protect and preserve unique ecosystems;[ HP G42-380LA CPU Fan

65 wetlands are listed under the Ramsar Convention,[187] and 16 natural World Heritage Sites have been established.[188] Australia was ranked 51st of 163 countries in the world on the 2010 Environmental Performance Index.[189]

Climate change has become an increasing concern in Australia in recent years, and protection of the environment is a major political issue.[ Toshiba Qosmio G30-167 CPU Fan

In 2007, the First Rudd Government signed the instrument of ratification of the Kyoto Protocol. Nevertheless, Australia's carbon dioxide emissions per capita are among the highest in the world, lower than those of only a few other industrialised nations.[192] Rainfall in Australia has slightly increased over the past century, HP Pavilion dv7-1157cl CPU Fan

both nationwide and for two quadrants of the nation,[193] According to the Bureau of Meteorology's 2011 Australian Climate Statement, Australia had lower than average temperatures in 2011 as a consequence of a La Niña weather pattern, however, "the country's 10-year average continues to demonstrate the rising trend in temperatures, Compaq Presario CQ40-408AX CPU Fan

with 2002–2011 likely to rank in the top two warmest 10-year periods on record for Australia, at 0.52 °C above the long-term average".[194] Water restrictions are frequently in place in many regions and cities of Australia in response to chronic shortages due to urban population increases and localised drought.[ HP Mini 110-1110ET CPU Fan

Throughout much of the continent, major flooding regularly follows extended periods of drought, flushing out inland river systems, overflowing dams and inundating large inland flood plains, as occurred throughout Eastern Australia in 2010, 2011 and 2012 after the 2000s Australian drought. HP Pavilion dv7-1157cl CPU Fan,HP Pavilion dv6-3163eo CPU Fan,HP Pavilion dv9740us CPU Fan

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