Thursday, November 14, 2013

The fossil record of birds in Australia is patchy

The fossil record of birds in Australia is patchy; however, there are records of the ancestors of contemporary species as early as the Late Oligocene.[57] Birds with a Gondwanan history include the flightless ratites (the Emu and Southern Cassowary),[58] HP Pavilion dv5-1102tu CPU Fan megapodes (the Malleefowl andAustralian Brush-turkey),[59] and a huge group of endemic parrots, order Psittaciformes. Australian parrots comprise a sixth of the world's parrots,[60] including many cockatoos and galahs.[61] The Kookaburra is the largest species of the kingfisherfamily, known for its call, which sounds uncannily like loud, echoing human laughter.[62] SONY VGN-SZ220 CPU Fan The passerines of Australia, also known as songbirds or perching birds,[63] include wrens,[64] robins,[65] the magpie group,[66] thornbills,[67] pardalotes,[68] the huge honeyeater family,[69] treecreepers,[70] lyrebirds,[71] Birds of Paradiseand bowerbirds.[72] HP Pavilion dv7-6011tx CPU Fan The Satin Bowerbird has attracted the interest of evolutionary psychologists; it has a complex courtship ritual in which the male creates a bower filled with blue, shiny items to woo mates.Relatively recent colonists from Eurasia are swallows,[ larks,[74] thrushes,[75]cisticolas, sunbirds, and some raptors, including the large Wedge-tailed Eagle.[ HP Pavilion dv5-1040eb CPU Fan ASUS F3Jv CPU Fan A number of bird species have been introduced by humans; some, like the European Goldfinch and Greenfinch,[76] coexist happily with Australian species,[ while others, such as the Common Starling, Common Blackbird, House Sparrow and Indian Mynah, are destructive of some native bird species and thus destabilise the native ecosystem. IBM ThinkPad R50p 2887 CPU Fan About 200 species of seabird live on the Australian coast, including many species of migratory seabird. Australia is at the southern end of the East Asian-Australasian flyway for migratory water birds, which extends from Far-East Russia and Alaska through Southeast Asia to Australia and New Zealand. SONY VGN-CS36GJ/R CPU Fan About two million birds travel this route to and from Australia each year.[ One very common large seabird is the Australian Pelican, which can be found in most waterways in Australia.[77] The Little Penguin is the only species of penguin that breeds on mainland Australia. Toshiba Satellite A215-S4807 CPU Fan Australia has four families of native frogs and one introduced toad, the Cane Toad.[80] In 1935 the Cane Toad was introduced to Australia in a failed attempt to control pests in sugarcane crops. It has since become a devastating pest, spreading across northern Australia. Toshiba Satellite Pro M10-SP405 CPU Fan As well as competing with native insectivores for food, the Cane Toad produces a venom that is toxic to native fauna,[81] as well as to humans.[82] The Myobatrachidae, or southern frogs,[83] are Australia's largest group of frogs, with 112 species classified into anywhere from 17 to 22 genera.[84] HP Pavilion dv4-1120us CPU Fan A notable member of this group is the colourful and endangered Corroboree Frog.[85] The tree frogs, from family Hylidae,[86] are common in high rainfall areas on the north and east coasts;[87] there are 77 Australian species from three genera.[Compaq Presario C550EM CPU Fan The 18 species from two genera of theMicrohylidae frogs are restricted to the rainforests of northern Australia and nearby habitats;[88] the smallest species, theScanty Frog, is from this family.[ There is a single species from the world's dominant frog group, familyRanidae — the Australian Wood Frog — which only occurs in the Queensland rainforests.[89] Toshiba Qosmio E15-AV101 CPU Fan As elsewhere, there has been a precipitous decline in Australia's frog populations in recent years.[90] Although the full reasons for the decline are uncertain, it can be at least partly attributed to the fatal amphibian fungal disease chytridiomycosis.[90] Another theory for the decline might be, Toshiba Satellite L645D-S4056 CPU Fan as research shows, that species from the Southern Hemisphere are on average 4.6 million years old, compared to an average 2.9 million years old for the Northern Hemisphere: Researchers believe this age difference is because of the history of severe Ice Ages in the Northern Hemisphere, which may drive older species to extinction. Toshiba Satellite A305-S6837 CPU Fan Australia has two species of crocodile. The Saltwater Crocodile, known colloquially as the "salty," is the largest living crocodile species; reaching over 7 m,[93] and weighing over 1,000 kg, they can and do kill people.[97] They live on the coast and in the freshwater rivers and wetlands of northern Australia, HP Pavilion dv7-4087cl CPU Fan and they are farmed for their meat and leather.[97] Freshwater Crocodiles, found only in northern Australia, are not considered dangerous to humans.[92] The Australian coast is visited by six species of sea turtle: the Flatback, Green Sea, Hawksbill, Olive Ridley, Loggerheadand the Leatherback Sea Turtles;[98] HP Pavilion dv5-1118es CPU Fan all are protected in Australian waters.[99] There are 29 species of Australian freshwaterturtles from eight genera of family Chelidae.[ The Pig-nosed Turtle is the only Australian turtle not of that family.[100] Australia is the only continent without any living species of land tortoise. Toshiba Satellite A665-S6050 CPU Fan Australia is the only continent[where venomous snakes outnumber their non-venomous cousins.[102] Australian snakes belong to seven families. Of these, the most venomous species,[ including the Fierce Snake,[103] Eastern Brown Snake,[104] Taipan andEastern Tiger Snake are from the family Elapidae.[105] HP Pavilion G72-259WM CPU Fan Of the 200 species of elapid, 86 are found only in Australia.[ Thirty-three sea snakes from family Hydrophiidae inhabit Australia's northern waters; many are extremely venomous. Two species of sea snake from the Acrochordidae also occur in Australian waters. Australia has only 11 species from the world's most significant snake family Colubridae; HP Pavilion dv6-3109ca  CPU  Fan none are endemic, and they are considered to be relatively recent arrivals from Asia. There are 15 python species and 31 species of insectivorous blind snake. There are more than 700 species of lizards in Australia[106] with representatives of five families.[107] HP Pavilion dv6782eg CPU Fan There are >130 species in 20 genera of gecko found throughout the Australian continent.[106] The Pygopodidae is a family of limbless lizards endemic to the Australian region;[108] all 39 species from seven genera occur in Australia.[106] The Agamidae or Dragon lizards are represented by 70 species in 14 genera,[106] SONY UDQF2PH52CF0 CPU Fan including the Thorny Devil, Bearded Dragon and Frill-necked Lizard.[109] There are 30 species ofmonitor lizard,[106] family Varanidae, in Australia, where they are commonly known as goannas.[110] The largest Australian monitor is the Perentie, which can reach up to 2 m in length.[111] Toshiba UDQFRPH33CCM CPU Fan There are 389 species of skink from 38 genera, comprising about 50% of the total Australian lizard fauna;[106] this group includes the blue-tongued lizards. More than 4,500 species of fish inhabit Australia's waterways;[113] of these, 90% are endemic. Toshiba Satellite A505-S6980 CPU Fan However, because of the relative scarcity of freshwater waterways, Australia has only about 300 species of freshwater fish.[114] Two families of freshwater fish have ancient origins: the arowana or bonytongues, and the Queensland Lungfish.[115] The Queensland Lungfish is the most primitive of the lungfish, having evolved before Australia separated from Gondwana.[ HP Pavilion dv7-2025es CPU Fan One of the smallest freshwater fish, peculiar to the southwest of Western Australia, is theSalamanderfish, which can survive desiccation in the dry season by burrowing into mud.[118] Other families with a potentially Gondwanan origin include the Retropinnidae, Galaxiidae, Aplochitonidae and Percichthyidae.[ TOSHIBA Satellite L300 CPU Fan Apart from the ancient freshwater species, 70% of Australia's freshwater fish have affinities with tropical Indo-Pacific marine species that have adapted to freshwater.[119] These species include freshwater lampreys,[120] herrings, catfish, rainbowfish, and some 50 species of gudgeon, including the Sleepy Cod.[121] HP G62-a10EJ CPU Fan Native freshwater game fish include the Barramundi,[122] Murray Cod, andGolden Perch.[123] Two species of endangered freshwater shark are found in the Northern Territory.[Several exotic freshwater fish species, including Brown, Brook and Rainbow Trout, Atlantic and Chinook Salmon, Dell MF60100V1-Q000-G99 CPU Fan Redfin Perch,Common Carp, and Mosquitofish, have been introduced to Australian waterways.[124] The Mosquitofish is a particularly aggressive species known for harassing and nipping the fins of other fish. It has been linked to declines and localised extirpations of several small native fish species. DELL R859C CPU Fan The introduced trout species have had serious negative impacts on a number of upland native fish species including Trout Cod, Macquarie Perch andmountain galaxias species as well as other upland fauna such as the Spotted Tree Frog. Toshiba Satellite A105-S2101 CPU Fan The Common Carp is strongly implicated in the dramatic loss in waterweed, decline of small native fish species and permanently elevated levels of turbidity in the Murray-Darling Basin of southwest Australia. Most of Australia's fish species are marine.[ SONY Vaio VGN-FW140E CPU Fan Groups of interest include the moray eels and squirrelfish,[126]as well as the pipefish and seahorses,[127] whose males incubate their partner's eggs in a specialised pouch.[125] There are 80 species of grouper in Australian waters,[ including one of the world's biggest bony fish, the Giant Grouper, ACER Aspire 5730Z CPU Fan which can grow as large as 2.7 m and weigh up to 400 kg.[128] The trevally, a group of 50 species of silver schooling fish, and the snappers are popular species for commercial fishing.[129] The Great Barrier Reef supports a huge variety of small- and medium-sized reef fish, including the damselfish, butterflyfish, angelfish,[130] SONY Vaio VPC-EB4S1E/WI CPU Fan gobies, cardinalfish, wrassees,[131]triggerfish and surgeonfish.[132] There are several venomous fish, among them several species of stonefish and pufferfish and the red lionfish, all of which have toxins that can kill humans.[133] There are 11 venomous species ofstingray,[ HP Pavilion dv9580ed CPU Fan the largest of which is the smooth stingray.[134] The barracudas are one of the reef's largest species.[135] However, large reef fish should not be eaten for fear of ciguatera poisoning. Sharks inhabit all the coastal waters and estuarine habitats of Australia's coast. Toshiba Satellite L305D-S5934 CPU Fan There are 166 species, including 30 species of requiem shark, 32 of catshark, six of wobbegong shark, and 40 of dogfish shark.[ There are three species from the family Heterodontidae: the Port Jackson shark, the zebra bullhead shark and the crested bullhead shark.[137] SONY Vaio VGN-CR31S/P CPU Fan In 2004, there were 12 unprovoked shark attacks in Australia, of which two were fatal.[138] Only 3 species of shark pose a significant threat to humans: the bull shark, the tiger shark and the great white shark. Some popular beaches in Queensland and New South Wales are protected by shark netting, HP Pavilion dv5-1210et CPU Fan a method that has reduced the population of both dangerous and harmless shark species through accidental entanglement.[ The overfishing of sharks has also significantly reduced shark numbers in Australian waters, and several species are now endangered.[ SONY Vaio VGN-FW465J/B CPU Fan A megamouth shark was found on a Perthbeach in 1988;[139] very little is known about this species, but this discovery may indicate the presence of the species in Australian coastal waters. Of the estimated 200,000 animal species in Australia, about 96% are invertebrates. HP Envy 15 CPU Fan While the full extent of invertebrate diversity is uncertain, 90% of insects and molluscs are considered endemic.[2] Invertebrates occupy many ecological niches and are important in all ecosystems as decomposers,[140] pollinators, and food sources.[141] HP Pavilion dv7-1190er CPU Fan The largest group of invertebrates is the insects, comprising 75% of Australia's known species of animals. The most diverse insect orders are the Coleoptera, with 28,200 species of beetles and weevils,[142] the Lepidoptera with 20,816 species[ including butterflies and moths,[143] Toshiba Satellite A105-S4074 CPU Fan and 12,781 species of Hymenoptera,[ including the ants, bees and wasps.[144] Order Diptera, which includes the flies and mosquitoes,[145] comprises 7,786 species,[ Order Hemiptera, including bugs, aphids and hoppers,[146] comprises 5,650 species; and there are 2,827 speciesof order Orthoptera, including grasshoppers, crickets and katydids.[147][14 IBM MCF-208AM05-1 CPU Fan 8]Introduced species that pose a significant threat to native species include the European wasp,[149] the red fire ant,[150] the yellow crazy ant[151] and feral honeybees which compete with native bees. Australia has a wide variety of arachnids, including 135 species of spider that are familiar enough to have common names. IBM MCF-217PAM05 CPU Fan There are numerous highly venomous species, including the notorious Sydney funnel-web and redback spiders, whose bites can be deadly.[155] There are thousands of species of mites and ticks from the subclass Acari.[156] Australia also has eight species of pseudoscorpionand nine scorpion species.  HP GB0507PGV1-A CPU Fan In the Annelida (sub)class Oligochaeta there are many families of aquatic worms, and for native terrestrial worms: the Enchytraeidae (pot worms) and the "true" earthworms in families Acanthodrilidae, Octochaetidae andMegascolecidae.The latter includes the world's largest earthworm, the giant Gippsland earthworm, IBM MCF-217PAM05 CPU Fan found only in Gippsland, Victoria.[157] On average they reach 80 cm in length, but specimens up to 3.7 m in length have been found. The large family Parastacidae includes 124 species of Australian freshwater crayfish.These include the world's smallest crayfish, the swamp crayfish, HP Pavilion dv6-3385la CPU Fan which does not exceed 30 mm in length,[158] and the world's largest crayfish, theTasmanian giant freshwater crayfish,[159] measuring up to 76 cm long and weighing 4.5 kg.[160] The crayfish genus Cheraxincludes the common yabby,[159] in addition to the farmed species marron and Queensland red claw. HP Pavilion tx2510us  CPU  Fan Species from the genusEngaeus, commonly known as the land crayfish, are also found in Australia. Engaeus species are not entirely aquatic, because they spend most of their lives living in burrows. Australia has seven species of freshwater crab from the genusAustrothelphusa. HP G62-b55EV CPU Fan These crabs live burrowed into the banks of waterways and can plug their burrows, surviving through several years of drought. The extremely primitive freshwater mountain shrimp, found only in Tasmania, are a unique group, resembling species found in the fossil record from 200 MYA. HP Pavilion dv6-2145sf CPU Fan A huge variety of marine invertebrates are found in Australian waters, with the Great Barrier Reef an important source of this diversity.Families include the Porifera or sea sponges,[161] the Cnidaria (includes the jellyfish, coralsand sea anemones, comb jellies),[162] the Echinodermata (includes the sea urchins, sea stars, brittle stars, sea cucumbers, the lamp shells)[163] HP Pavilion dv7-1120ew CPU Fan and the Mollusca (includes snails, slugs, limpets, squid, octopus, cockles, oysters, clams, andchitons).[164] Venomous invertebrates include the box jellyfish, the blue-ringed octopus,[165] and ten species of cone snail,which can cause respiratory failure and death in humans.[165] HP 538340-001 CPU Fan The crown-of-thorns starfish usually inhabits the Reef at low densities. However, under conditions that are not yet well understood, they can reproduce to reach an unsustainable population density when coral is devoured at a rate faster than it can regenerate. HP 535766-001 CPU Fan This presents a serious reef management issue.Other problematic marine invertebrates include the native species purple sea urchin and the white urchin, which have been able to take over marine habitats and form urchin barrens due to the over harvesting of their natural predators which include abalone and rock lobster. HP 535442-001 CPU Fan Introduced invertebrate pests include theAsian mussel, New Zealand green-lipped mussel, black-striped mussel and the Northern Pacific seastar, all of which displace native shellfish.[] There are many unique marine crustaceans in Australian waters. HP 535441-001 CPU Fan The best-known class, to which all the edible species of crustacean belong, is Malacostraca.The warm waters of northern Australia are home to many species of decapodcrustaceans, including crabs, false crabs, hermit crabs, lobsters, shrimps, and prawns. HP 535439-001 CPU Fan The peracarids, including theamphipods and isopods, are more diverse in the colder waters of southern Australia.Less-well-known marine groups include the classes Remipedia, Cephalocarida, Branchiopoda, Maxillopoda (which includes the barnacles, copepods andfish lice), and the Ostracoda.[166] HP 535438-001 CPU Fan Notable species include the Tasmanian giant crab, the second largest crab species in the world,[167] found in deep water, and weighing up to 13 kg,[168] and the Australian spiny lobsters, such as the Western rock lobster, which are distinct from other lobster species as they do not have claws. HP 533736-001 CPU Fan Introduction of exotic fauna in Australia by design, accident and natural processes has led to a considerable number ofinvasive, feral and pest species which have flourished and now impact the environment adversely. Introduced organisms affect the environment in a number of ways. IBM 13R2760 CPU Fan Rabbits render land economically useless by eating everything.[169] Red Foxes affect local endemic fauna by predation while the cane toad poisons the predators by being eaten.[170] The invasive species include birds (Indian Mynah) and fish (common carp), insects (red imported fire ant) and molluscs (Asian mussel). ACER LU.S040A.067 CPU Fan The problem is compounded by invasive exotic flora as well as introduced diseases, fungi and parasites.Costly, laborious and time-consuming efforts at control of these species has met with little success and this continues to be a major problem area in the conservation of Australia's biodiversity. ACER LU.S050B.078 CPU Fan For at least 40,000 years, Australia's fauna played an integral role in the traditional lifestyles of Indigenous Australians, who exploited many species as a source of food and skins. Vertebrates commonly harvested included macropods, opossums, seals, fish and the Short-tailed Shearwater, most commonly known as the Muttonbird. DELL Studio 1535 CPU Fan Invertebrates used as food included insects such as the Bogong moth and larvae collectively called witchetty grubs and molluscs. The use of fire-stick farming, in which large swathes of bushland were burnt to facilitate hunting, modified both flora and fauna — and are thought to have contributed to the extinction of large herbivores with a specialised diet, HP Pavilion dv6736nr CPU Fan such as the flightless birds from the genus Genyornis.[171] The role of hunting and landscape modification by aboriginal people in the extinction of the Australian megafauna is debated. The impact of Aborigines on native species populations is widely considered to be less significant than that of the European settlers,[172] HP Envy 15-1050ca CPU Fan whose impact on the landscape has been on a relatively large scale. Since European settlement, direct exploitation of native fauna, habitat destruction and the introduction of exotic predators and competitive herbivores has led to the extinction of some 27 mammal, 23 bird and 4 frog species. HP Pavilion dv7-6100et CPU Fan Much of Australia's fauna is protected by legislation.[1]The federal Environment Protection and Biodiversity Conservation Act 1999 was created to meet Australia's obligations as a signatory to the 1992 Convention on Biological Diversity. APPLE 661-4951 CPU Fan IBM 42W2403 CPU Fan This act protects all native fauna and provides for the identification and protection of threatened species. In each state and territory, there is statutory listing of threatened species. At present, 380 animal species are classified as either endangered or threatened under the EPBC Act, and other species are protected under state and territory legislation.[173] ACER Aspire 9304WSMi CPU Fan More broadly, a complete cataloguing of all the species within Australia has been undertaken, a key step in the conservation of Australian fauna and biodiversity. In 1973, the federal government established the Australian Biological Resources Study (ABRS), which coordinates research in the taxonomy, HP 610773-001 CPU Fan identification, classification and distribution of flora and fauna. The ABRS maintains free online databases cataloguing much of the described Australian flora and fauna. Impacts such as the illegal setting of traps in rivers affect animals such as the Australian platypus, IBM ThinkPad R50p 1830 CPU Fan along with lack of awareness each year an average of 2–5 Australians lose their lives to what is presumed a safe creature. The key is understanding of Australia's diverse wildlife and fauna; what seems safe is often deadly. Australia is a member of the International Whaling Commission IBM ThinkPad T61 8898 CPU Fan and is strongly opposed to commercial whaling—all Cetacean species are protected in Australian waters.[174] Australia is also a signatory to the CITES agreement and prohibits the export of endangered species. Protected areas have been created in every state and territory to protect and preserve the country's unique ecosystems. IBM ThinkPad R50p 2889 CPU Fan These protected areas include national parks and other reserves, as well as 64 wetlands registered under the Ramsar Convention and 16 World Heritage Sites. As of 2002, 10.8% (774,619.51 km²) of the total land area of Australia is within protected areas.[175] IBM ThinkPad R50p 1830 CPU Fan Protected marine zones have been created in many areas to preserve marine biodiversity; as of 2002, these areas cover about 7% (646,000 km²) of Australia's marine jurisdiction.[176] The Great Barrier Reef is managed by the Great Barrier Reef Marine Park Authority under specific federal and state legislation. IBM ThinkPad R50 1829 CPU Fan Some of Australia's fisheries are already overexploited,[177] and quotas have been set for the sustainable harvest of many marine species. The State of the Environment Report, 2001, prepared by independent researchers for the federal government, IBM ThinkPad R50P CPU Fan concluded that the condition of the environment and environmental management in Australia had worsened since the previous report in 1996. Of particular relevance to wildlife conservation, the report indicated that many processes—such as salinity, IBM Thinkpad W500 CPU Fan changing hydrological conditions, land clearing, fragmentation of ecosystems, poor management of the coastal environment, and invasive species—pose major problems for protecting Australia's biodiversity. HP G62-374CA CPU Fan,HP Pavilion dv5-1203eg CPU Fan,HP Pavilion dv7-3131ez CPU Fan

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