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Platypus

From Wikipedia - Reading time: 37 min
For other uses, see Platypus (disambiguation).

Platypus
Temporal range: Pliocene–Recent
Platypus swimming in waters near Scottsdale, Tasmania
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Monotremata
Family: Ornithorhynchidae
Genus: Ornithorhynchus
Blumenbach, 1800
Species:
O. anatinus
Binomial name
Ornithorhynchus anatinus
(Shaw, 1799)
Platypus range
(red – native, yellow – introduced)
Synonyms[2][3]
  • Platypus anatinus Shaw, 1799
  • Ornithorhynchus paradoxus Blumenbach, 1800
  • O. novaehollandiae Lacépède, 1800
  • O. fuscus Péron, 1807
  • O. rufus Péron, 1807
  • O. paradoxi Meckel, 1826
  • O. crispus MacGillivray, 1827
  • O. laevis MacGillivray, 1827
  • O. brevirostris Ogilby, 1832
  • O. agilis de Vis, 1886
  • O. phoxinus O. Thomas, 1923
  • O. triton O. Thomas, 1923

The platypus (Ornithorhynchus anatinus),[4] sometimes referred to as the duck-billed platypus,[5] is a semiaquatic, egg-laying mammal endemic to eastern Australia, including Tasmania. The platypus is the sole living representative or monotypic taxon of its family Ornithorhynchidae and genus Ornithorhynchus, though a number of related species appear in the fossil record.

Together with the four species of echidna, it is one of the five extant species of monotremes, mammals that lay eggs instead of giving birth to live young.[6] Like other monotremes, the platypus has a sense of electrolocation, which it uses to detect prey in cloudy water.[7] It is one of the few species of venomous mammals, as the male platypus has a spur on the hind foot that delivers an extremely painful venom.

The unusual appearance of this egg-laying, duck-billed, beaver-tailed, otter-footed mammal at first baffled European naturalists. In 1799, the first scientists to examine a preserved platypus body judged it a fake made of several animals sewn together.

The unique features of the platypus make it important in the study of evolutionary biology, and a recognisable and iconic symbol of Australia. It is culturally significant to several Aboriginal peoples, who also used to hunt it for food. It has appeared as a national mascot, features on the reverse of the Australian twenty-cent coin, and is an emblem of the state of New South Wales.

The platypus was hunted for its fur, but it has been a legally protected species in all states where it occurs since 1912.[8] Its population is not under severe threat, although captive-breeding programs have had slight success, and it is vulnerable to pollution. It is classified as a near-threatened species by the IUCN, but a November 2020 report has recommended that it be upgraded to threatened species under the federal EPBC Act, due to habitat destruction and declining numbers in all states.[9]

Taxonomy and naming

[edit]
See also: Plural form of words ending in -us

Australian Aboriginal people name or have named the platypus in various ways depending on Australian indigenous languages and dialects. Among the names found: boondaburra, mallingong, tambreet, watjarang[10] (names in Yass, Murrumbidgee, and Tumut),[11] tohunbuck (region of Goomburra, Darling Downs),[11] dulaiwarrung[12] ou dulai warrung (Woiwurrung language, Wurundjeri, Victoria),[13] djanbang (Bundjalung, Queensland),[14] djumulung (Yuin language, Yuin, New South Wales),[15] maluŋgaŋ (ngunnawal language, Ngunnawal, Australian Capital Territory[16]), biladurang, wamul, dyiimalung, oornie, dungidany (Wiradjuri language, Wiradjuri, Vic, NSW),[13] oonah,[17] etc. The name chosen and approved in Palawa kani (reconstructed tasmanian language) is larila.[18]

When the platypus was first encountered by Europeans in 1798, a pelt and sketch were sent back to Great Britain by Captain John Hunter, the second Governor of New South Wales.[19] British scientists' initial hunch was that the attributes were a hoax.[20] George Shaw, who produced the first description of the animal in the Naturalist's Miscellany in 1799, stated it was impossible not to entertain doubts as to its genuine nature,[5] and Robert Knox believed it might have been produced by some Asian taxidermist.[20] It was thought that somebody had sewn a duck's beak onto the body of a beaver-like animal. Shaw even took a pair of scissors to the dried skin to check for stitches.[21][5]

The common name "platypus" literally means 'flat-foot', deriving from the Greek word platúpous (πλατύπους),[22] from platús (πλατύς 'broad, wide, flat')[23][a] and poús (πούς 'foot').[24][25] Shaw initially assigned the species the Linnaean name Platypus anatinus when he described it,[5] but the genus term was quickly discovered to already be in use as the name of the wood-boring ambrosia beetle genus Platypus.[26] It was independently described as Ornithorhynchus paradoxus by Johann Blumenbach in 1800 (from a specimen given to him by Sir Joseph Banks)[27] and following the rules of priority of nomenclature, it was later officially recognised as Ornithorhynchus anatinus.[26]

There is no universally agreed plural form of "platypus" in the English language. Scientists generally use "platypuses" or simply "platypus". Alternatively, the term "platypi" is also used for the plural, although this is a form of pseudo-Latin;[21] going by the word's Greek roots the plural would be "platypodes". Early British settlers called it by many names, such as "watermole", "duckbill", and "duckmole".[21] Occasionally it is specifically called the "duck-billed platypus".

The scientific name Ornithorhynchus anatinus literally means 'duck-like bird-snout',[5] deriving its genus name from the Greek root ornith- (όρνιθ ornith or ὄρνις órnīs 'bird')[28] and the word rhúnkhos (ῥύγχος 'snout', 'beak').[29] Its species name is derived from Latin anatinus ('duck-like') from anas 'duck'.[5][30] The platypus is the sole living representative or monotypic taxon of its family (Ornithorhynchidae).[31]

  • A book for children published in Germany in 1798
    A book for children published in Germany in 1798
  • Illustration from the first scientific description in 1799
    Illustration from the first scientific description in 1799
  • Colour print from 1863
    Colour print from 1863

Description

[edit]

In David Collins's account of the new colony 1788–1801, he describes "an amphibious animal, of the mole species", with a drawing.[32]

The body and the broad, flat tail of the platypus are covered with dense, brown, biofluorescent fur that traps a layer of insulating air to keep the animal warm.[21][26][33] The fur is waterproof, and textured like that of a mole.[34] The platypus's tail stores fat reserves, an adaptation also found in the Tasmanian devil.[35] Webbing is more significant on the front feet, which in land walking are folded up in knuckle-walking to protect the webbing.[36] The elongated snout and lower jaw are covered in soft skin, forming the bill. The nostrils are located on the snout's dorsal surface, while the eyes and ears are just behind the snout in a groove which closes underwater.[26] Platypuses can give a low growl when disturbed, and a range of vocalisations have been reported in captivity.[21]

Size varies considerably in different regions, with average weight from 0.7 to 2.4 kg (1 lb 9 oz to 5 lb 5 oz); males have average length 50 cm (20 in), while females are the smaller at 43 cm (17 in).[26] This variation does not seem to follow any particular climatic rule and may be due to other factors such as predation and human encroachment.[37]

The platypus has an average body temperature of about 32 °C (90 °F), lower than the 37 °C (99 °F) typical of placental mammals.[38] Research suggests this has been a gradual adaptation to harsh environmental conditions among the few marginal surviving monotreme species, rather than a general characteristic of past monotremes.[39][40]

In addition to laying eggs, the anatomy, ontogeny, and genetics of monotremes shows traces of similarity to reptiles and birds. The platypus has a reptilian gait with legs on the sides of the body, rather than underneath.[26] The platypus's genes are a possible evolutionary link between the mammalian XY and bird/reptile ZW sex-determination systems, as one of the platypus's five X chromosomes contains the DMRT1 gene, which birds possess on their Z chromosome.[41]

As in all true mammals, the tiny bones that conduct sound in the middle ear are fully incorporated into the skull, rather than lying in the jaw as in pre-mammalian synapsids. However, the external opening of the ear still lies at the base of the jaw.[26] The platypus has extra bones in the shoulder girdle, including an interclavicle not found in other mammals.[26] As in many other aquatic and semiaquatic vertebrates, the bones show osteosclerosis, increasing their density to provide ballast.[42]

The platypus jaw is constructed differently from that of other mammals, and the jaw-opening muscle is different.[26] Modern platypus young have three teeth in each of the maxillae (one premolar and two molars) and dentaries (three molars), which they lose before or just after leaving the breeding burrow;[26] adults instead develop heavily keratinised food-grinding pads called ceratodontes.[26][43][44] The first upper and third lower cheek teeth of platypus nestlings are small, each having one principal cusp, while the other teeth have two main cusps.[45]

  • Diving
    Diving
  • Surfacing
    Surfacing

Venom

[edit]
Main article: Platypus venom
The calcaneus spur on the male's hind limb is used to inject venom.

While both male and female platypuses are born with back ankle spurs, only the males' deliver venom.[46][47][48] It is powerful enough to kill smaller animals such as dogs, and though it is not lethal to humans, it can inflict weeks of agony.[49][50] Edema rapidly develops around the wound and gradually spreads through the affected limb, and it may develop into an excruciating hyperalgesia (heightened sensitivity to pain) persisting for days or even months.[51][52]

The venom is composed largely of defensin-like proteins (DLPs) produced by the immune system, three of which are unique to the platypus.[49] In other animals, defensins kill pathogenic bacteria and viruses, but in platypuses they are also collected into a venom against predators. Venom is produced in the crural glands of the male, which are kidney-shaped alveolar glands connected by a thin-walled duct to a calcaneus spur on each hind limb. The female platypus, in common with echidnas, has rudimentary spur buds that do not develop (dropping off before the end of their first year) and lack functional crural glands.[26] Venom production rises among males during the breeding season, and it may be used to assert dominance.[49]

Similar spurs are found on many archaic mammal groups, indicating that this was an ancient general characteristic among mammals.[53]

Electrolocation

[edit]
The platypus has secondarily acquired electroreception. Its receptors are arranged in stripes on its bill, giving it high sensitivity to the sides and below; it makes quick turns of its head as it swims to detect prey.[54]

Monotremes are the only mammals (apart from the Guiana dolphin)[55] known to have a sense of electroreception, and the platypus's electroreception is the most sensitive of any monotreme.[56][54] Feeding by neither sight nor smell,[57] the platypus closes its eyes, ears, and nose when it dives.[58] Digging in the bottom of streams with its bill, its electroreceptors detect tiny electric currents generated by the muscular contractions of its prey, enabling it to distinguish between animate and inanimate objects.[54] Experiments have shown the platypus will even react to an "artificial shrimp" if a small electric current is passed through it.[59]

The electroreceptors are located in rostrocaudal rows in the skin of the bill, while mechanoreceptors for touch are uniformly distributed across the bill. The electrosensory area of the cerebral cortex is in the tactile somatosensory area, and some cortical cells receive input from both electroreceptors and mechanoreceptors, suggesting the platypus feels electric fields like touches. These receptors in the bill dominate the somatotopic map of the platypus brain, in the same way human hands dominate the Penfield homunculus map.[60][61]

The platypus can feel the direction of an electric source, perhaps by comparing differences in signal strength across the sheet of electroreceptors, enhanced by the characteristic side-to-side motion of the animal's head while hunting. It may also be able to determine the distance of moving prey from the time lag between their electrical and mechanical pressure pulses.[54]

Monotreme electrolocation for hunting in murky waters may be tied to their tooth loss.[62] The extinct Obdurodon was electroreceptive, but unlike the modern platypus it foraged pelagically (near the ocean surface).[62]

Eyes

[edit]

In recent studies it has been suggested that the eyes of the platypus are more similar to those of Pacific hagfish or Northern Hemisphere lampreys than to those of most tetrapods. The eyes also contain double cones, unlike most mammals.[63]

Although the platypus's eyes are small and not used under water, several features indicate that vision was important for its ancestors. The corneal surface and the adjacent surface of the lens is flat, while the posterior surface of the lens is steeply curved, similar to the eyes of other aquatic mammals such as otters and sea-lions. A temporal (ear side) concentration of retinal ganglion cells, important for binocular vision, indicates a vestigial role in predation, though the actual visual acuity is insufficient for such activities. Limited acuity is matched by low cortical magnification, a small lateral geniculate nucleus, and a large optic tectum, suggesting that the visual midbrain plays a more important role than the visual cortex, as in some rodents. These features suggest that the platypus has adapted to an aquatic and nocturnal lifestyle, developing its electrosensory system at the cost of its visual system. This contrasts with the small number of electroreceptors in the short-beaked echidna, which dwells in dry environments, while the long-beaked echidna, which lives in moist environments, is intermediate between the other two monotremes.[60]

Biofluorescence

[edit]

In 2020, research revealed that platypus fur gives a bluish-green biofluorescent glow in black light.[64]

Distribution, ecology, and behaviour

[edit]
Dentition, as illustrated in Knight's Sketches in Natural History
Swimming underwater at Sydney Aquarium, Australia

The platypus is semiaquatic, inhabiting small streams and rivers over an extensive range from the cold highlands of Tasmania and the Australian Alps to the tropical rainforests of coastal Queensland as far north as the base of the Cape York Peninsula.[65]

Inland, its distribution is not well known. It was considered extinct on the South Australian mainland, with the last sighting recorded at Renmark in 1975.[66] In the 1980s, John Wamsley created a platypus breeding program in Warrawong Sanctuary (see below), which subsequently closed.[67][68] In 2017 there were some unconfirmed sightings downstream from the sanctuary,[66] and in October 2020 a nesting platypus was filmed inside the recently reopened sanctuary.[69]

There is a population on Kangaroo Island[70] introduced in the 1920s, said to stand at 150 individuals in the Rocky River region of Flinders Chase National Park. In the 2019–20 Australian bushfire season, large portions of the island burnt, decimating wildlife. However, SA Department for Environment and Water recovery teams worked to reinstate their habitat, with a number of sightings reported by April 2020.[71]

The platypus is no longer found in the main Murray–Darling Basin, possibly due to declining water quality from land clearing and irrigation[72] although it is found in the Goulburn River in Victoria.[73] Along the coastal river systems, its distribution is unpredictable: absent in some relatively healthy rivers, but present in some quite degraded ones, for example the lower Maribyrnong.[74]

In captivity, platypuses have survived to 30 years of age, and wild specimens have been recaptured when 24 years old. Mortality rates for adults in the wild appear to be low.[75] Natural predators include snakes, water rats, goannas, hawks, owls, and eagles. Low platypus numbers in northern Australia are possibly due to predation by crocodiles.[76] The introduction of red foxes in 1845 for sport hunting may have had some impact on its numbers on the mainland.[37] The platypus is generally nocturnal and crepuscular, but can be active on overcast days.[77][78] Its habitat bridges rivers and the riparian zone, where it finds both prey and river banks to dig resting and nesting burrows.[78] It may have a range of up to 7 km (4.3 mi), with a male's home range overlapping those of three or four females.[79]

The platypus is an excellent swimmer and spends much of its time in the water foraging for food. It has a swimming style unique among mammals,[80] propelling itself by alternate strokes of the front feet, while the webbed hind feet are held against the body and only used for steering, along with the tail.[81] It can maintain its relatively low body temperature of about 32 °C (90 °F) while foraging for hours in water below 5 °C (41 °F).[26] Dives normally last around 30 seconds, with an estimated aerobic limit of 40 seconds, with 10 to 20 seconds at the surface between dives.[82][83]

The platypus rests in a short, straight burrow in the riverbank about 30 cm (12 in) above water level, its oval entrance-hole often hidden under a tangle of roots.[80] It may sleep up to 14 hours per day, after half a day of diving.[84]

Diet

[edit]

The platypus is a carnivore, feeding on annelid worms, insect larvae, freshwater shrimp, and yabby (crayfish) that it digs out of the riverbed with its snout or catches while swimming. It carries prey to the surface in cheek-pouches before eating it.[80] It eats about 20% of its own weight each day, which requires it to spend an average of 12 hours daily looking for food.[82]

Reproduction

[edit]
Platypus's nest with eggs (replica)

The species has a single breeding season between June and October, with some local variation.[76] Investigations have found both resident and transient platypuses, and suggest a polygynous mating system.[85] Females are believed to become sexually mature in their second year, with breeding observed in animals over nine years old.[85] During copulation, the male grasps the female's tail with his bill, wraps his tail around her, then grips her neck or shoulder, everts his penis through his cloaca, and inserts it into her urogenital sinus.[86] He takes no part in nesting, living in his year-long resting burrow. After mating, the female constructs a deep, elaborate nesting burrow up to 20 m (65 ft) long.[87] She tucks fallen leaves and reeds underneath her curled tail, dragging them to the burrow to soften the tunnel floor with folded wet leaves, and to line the nest at the end with bedding.[21]

The female has two ovaries, but only the left one is functional.[88][77] She lays one to three (usually two) small, leathery eggs (similar to those of reptiles), about 11 mm (7⁄16 in) in diameter and slightly rounder than bird eggs.[89] The eggs develop in utero for about 28 days, with only about 10 days of external incubation (in contrast to a chicken egg, which spends about one day in tract and 21 days externally).[77] The female curls around the incubating eggs, which develop in three phases.[90] In the first, the embryo has no functional organs and relies on the yolk sac for sustenance, until the sac is absorbed.[91] During the second phase, the digits develop, and in the last phase, the egg tooth appears.[90] At first, European naturalists could hardly believe that the female platypus lays eggs, but this was finally confirmed by William Hay Caldwell in 1884.[26][49]

Most mammal zygotes go through holoblastic cleavage, splitting into multiple divisible daughter cells. However, monotremes like the platypus, along with reptiles and birds, undergo meroblastic cleavage, in which the ovum does not split completely. The cells at the edge of the yolk remain continuous with the egg's cytoplasm, allowing the yolk and embryo to exchange waste and nutrients with the egg through the cytoplasm.[92]

Young platypus are called "puggles". Newly hatched platypuses are vulnerable, blind, and hairless, and are fed by the mother's milk, that provides all the requirements for growth and development.[93][94] The platypus's mammary glands lack teats, with milk released through pores in the skin. The milk pools in grooves on the mother's abdomen, allowing the young to lap it up.[21][76] After they hatch, the offspring are milk-fed for three to four months.

During incubation and weaning, the mother initially leaves the burrow only for short periods to forage. She leaves behind her a number of thin soil plugs along the length of the burrow, possibly to protect the young from predators; pushing past these on her return squeezes water from her fur and allows the burrow to remain dry.[95] After about five weeks, the mother begins to spend more time away from her young, and at around four months, the young emerge from the burrow.[76] A platypus is born with teeth, but these drop out at a very early age, leaving the horny plates it uses to grind food.[43]

Evolution

[edit]

Platypus

Echidnas

 live birth 

Marsupials

 true placenta 

Eutherians

Evolutionary relationships between the platypus and other mammals[96]

The platypus and other monotremes were very poorly understood, and some of the 19th century myths that grew up around them – for example, that the monotremes were "inferior" or quasireptilian – still endure.[97] In 1947, William King Gregory theorised that placental mammals and marsupials may have diverged earlier, and a subsequent branching divided the monotremes and marsupials, but later research and fossil discoveries have suggested this is incorrect.[97][98] In fact, modern monotremes are the survivors of an early branching of the mammal tree, and a later branching is thought to have led to the marsupial and placental groups.[97][99] Molecular clock and fossil dating suggest platypuses split from echidnas around 19–48 million years ago.[100]

Reconstruction of ancient platypus relative Steropodon

The oldest discovered fossil of the modern platypus dates back to about 100,000 years ago during the Quaternary period, though a limb bone of Ornithorhynchus is known from Pliocene-aged strata.[101] The extinct monotremes Teinolophos and Steropodon from the Cretaceous were once thought to be closely related to the modern platypus,[98] but are now considered more basal taxa.[102] The fossilised Steropodon was discovered in New South Wales and is composed of an opalised lower jawbone with three molar teeth (whereas the adult contemporary platypus is toothless). The molar teeth were initially thought to be tribosphenic, which would have supported a variation of Gregory's theory, but later research has suggested, while they have three cusps, they evolved under a separate process.[103] The fossil jaw of Teinolophos is thought to be about 110 million years old, making it the oldest mammal fossil found in Australia. Unlike the modern platypus (and echidnas), Teinolophos lacked a beak.[102]

In 2024, Late Cretaceous (Cenomanian)-aged fossil specimens of actual early platypus relatives were recovered from the same rocks as Steropodon, including the basal Opalios and the more derived Dharragarra, the latter of which may be the oldest member of the platypus stem-lineage, as it retains the same dental formula found in Cenozoic platypus relatives.[104] Monotrematum and Patagorhynchus, two other fossil relatives of the platypus, are known from the latest Cretaceous (Maastrichtian) and the mid-Paleocene of Argentina, indicating that some monotremes managed to colonize South America from Australia when the two continents were connected via Antarctica. These are also considered potential members of the platypus stem-lineage.[103][105][104] The closest fossil relative of the platypus was Obdurodon, known from the late Oligocene to the Miocene of Australia. It closely resembled the modern platypus, aside from the presence of molar teeth.[104] A fossilised tooth of the giant platypus Obdurodon tharalkooschild was dated 5–15 million years ago. Judging by the tooth, the animal measured 1.3 metres long, making it the largest platypus on record.[106]

The loss of teeth in the modern platypus has long been enigmatic, as a distinctive lower molar tooth row was previously present in its lineage for over 95 million years. Even its closest relative, Obdurodon, which otherwise closely resembles the platypus, retained this tooth row. More recent studies indicate that this tooth loss was a geologically very recent event, occurring only around the Plio-Pleistocene (around 2.5 million years ago), when the rakali, a large semiaquatic rodent, colonized Australia from New Guinea. The platypus, which previously fed on a wide array of hard and soft-bodied prey, was outcompeted by the rakali over hard-bodied prey such as crayfish and mussels. This competition may have selected for the loss of teeth in the platypus and their replacement by horny pads, as a way of specializing for softer-bodied prey, which the rakali did not compete with it over.[104]

Genome

[edit]
Platypus skeleton

Because of the early divergence from the therian mammals and the low numbers of extant monotreme species, the platypus is a frequent subject of research in evolutionary biology. In 2004, researchers at the Australian National University discovered the platypus has ten sex chromosomes, compared with two (XY) in most other mammals. These ten chromosomes form five unique pairs of XY in males and XX in females, i.e. males are X1Y1X2Y2X3Y3X4Y4X5Y5.[107] One of the X chromosomes of the platypus has great homology to the bird Z chromosome.[108] The platypus genome also has both reptilian and mammalian genes associated with egg fertilisation.[57][109] Though the platypus lacks the mammalian sex-determining gene SRY, a study found that the mechanism of sex determination is the AMH gene on the oldest Y chromosome.[110][111] A draft version of the platypus genome sequence was published in Nature on 8 May 2008, revealing both reptilian and mammalian elements, as well as two genes found previously only in birds, amphibians, and fish. More than 80% of the platypus's genes are common to the other mammals whose genomes have been sequenced.[57] An updated genome, the most complete on record, was published in 2021, together with the genome of the short-beaked echidna.[112]

Conservation

[edit]

Status and threats

[edit]

Except for its loss from the state of South Australia, the platypus occupies the same general distribution as it did prior to European settlement of Australia. However, local changes and fragmentation of distribution due to human modification of its habitat are documented. Its historical abundance is unknown and its current abundance difficult to gauge, but it is assumed to have declined in numbers, although as of 1998 was still being considered as common over most of its current range.[78] The species was extensively hunted for its fur until the early years of the 20th century. Although the species gained legal protections beginning in Victoria in 1890[113] and throughout Australia by 1912,[8] until about 1950 it was still at risk of drowning in the nets of inland fisheries.[72]

The International Union for Conservation of Nature recategorised its status as "near threatened" in 2016.[114] The species is protected by law, but the only state in which it is listed as endangered is South Australia, under the National Parks and Wildlife Act 1972. In November 2020 a recommendation was made to list the platypus as a vulnerable species across all states[9] with a vulnerable listing being made official in Victoria under the state's Flora and Fauna Guarantee Act 1988 on 10 January 2021.[115]

Habitat destruction

[edit]

The platypus is not considered to be in immediate danger of extinction, because conservation measures have been successful, but it could be adversely affected by habitat disruption caused by dams, irrigation, pollution, netting, and trapping.[116] Reduction of watercourse flows and water levels through excessive droughts and extraction of water for industrial, agricultural, and domestic supplies are also considered a threat. The IUCN lists the platypus on its Red List as "Near Threatened"[1] as assessed in 2016, when it was estimated that numbers had reduced by about 30 percent on average since European settlement. The animal is listed as endangered in South Australia, but it is not covered at all under the federal EPBC Act.[117][118]

Researchers have worried for years that declines have been greater than assumed.[117] In January 2020, researchers from the University of New South Wales presented evidence that the platypus is at risk of extinction, due to a combination of extraction of water resources, land clearing, climate change and severe drought.[119][120] The study predicted that, considering current threats, the animals' abundance would decline by 47–66% and metapopulation occupancy by 22–32% over 50 years, causing "extinction of local populations across about 40% of the range". Under projections of climate change projections to 2070, reduced habitat due to drought would lead to 51–73% reduced abundance and 36–56% reduced metapopulation occupancy within 50 years respectively. These predictions suggested that the species would fall under the "Vulnerable" classification. The authors stressed the need for national conservation efforts, which might include conducting more surveys, tracking trends, reduction of threats and improvement of river management to ensure healthy platypus habitat.[121] Co-author Gilad Bino is concerned that the estimates of the 2016 baseline numbers could be wrong, and numbers may have been reduced by as much as half already.[117]

A November 2020 report by scientists from the University of New South Wales, funded by a research grant from the Australian Conservation Foundation in collaboration with the World Wildlife Fund Australia and the Humane Society International Australia revealed that that platypus habitat in Australia had shrunk by 22 per cent in the previous 30 years, and recommended that the platypus should be listed as a threatened species under the EPBC Act.[9][122] Declines in population had been greatest in NSW, in particular in the Murray–Darling basin.[123][9]

Disease

[edit]

Platypuses generally suffer from few diseases in the wild; however, as of 2008 there was concern in Tasmania about the potential impacts of a disease caused by the fungus Mucor amphibiorum. The disease (termed mucormycosis) affects only Tasmanian platypuses, and had not been observed in platypuses in mainland Australia. Affected platypuses can develop skin lesions or ulcers on various parts of their bodies, including their backs, tails, and legs. Mucormycosis can kill platypuses, death arising from secondary infection and by affecting the animals' ability to maintain body temperature and forage efficiently. The Biodiversity Conservation Branch at the Department of Primary Industries and Water collaborated with NRM north and University of Tasmania researchers to determine the impacts of the disease on Tasmanian platypuses, as well as the mechanism of transmission and spread of the disease.[124]

Wildlife sanctuaries

[edit]

Much of the world was introduced to the platypus in 1939 when National Geographic Magazine published an article on the platypus and the efforts to study and raise it in captivity. The latter is a difficult task, and only a few young have been successfully raised since, notably at Healesville Sanctuary in Victoria. The leading figure in these efforts was David Fleay, who established a platypusary (a simulated stream in a tank) at the Healesville Sanctuary, where breeding was successful in 1943.[125] In 1972, he found a dead baby of about 50 days old, which had presumably been born in captivity, at his wildlife park at Burleigh Heads on the Gold Coast, Queensland.[126] Healesville repeated its success in 1998 and again in 2000 with a similar stream tank.[127] Since 2008, platypus has bred regularly at Healesville,[128] including second-generation (captive born themselves breeding in captivity).[129] Taronga Zoo in Sydney bred twins in 2003, and breeding was again successful there in 2006.[127]

Captivity

[edit]

As of 2019, the only platypuses in captivity outside of Australia are in the San Diego Zoo Safari Park in the U.S. state of California.[130][131] Three attempts were made to bring the animals to the Bronx Zoo, in 1922, 1947, and 1958. Of these, only two of the three animals introduced in 1947, Penelope and Cecil,[132] lived longer than eighteen months.[133]

Human interactions

[edit]

Usage

[edit]

Aboriginal Australians used to hunt platypuses for food (their fatty tails being particularly nutritious), while, after colonisation, Europeans hunted them for fur from the late 19th century until 1912, when it was prohibited by law.[134] In addition, European researchers captured and killed platypus or removed their eggs, partly in order to increase scientific knowledge, but also to gain prestige and outcompete rivals from different countries.[9]

Cultural references

[edit]

The platypus has been a subject in the Dreamtime stories of Aboriginal Australians, some of whom believed the animal was a hybrid of a duck and a water rat.[135]: 57–60 

According to one story of the upper Darling River,[9] the major animal groups, the land animals, water animals and birds, all competed for the platypus to join their respective groups, but the platypus ultimately decided to not join any of them, feeling that he did not need to be part of a group to be special,[135]: 83–85  and wished to remain friends with all of those groups.[9] Another Dreaming story emanate of the upper Darling tells of a young duck which ventured too far, ignoring the warnings of her tribe, and was kidnapped by a large water-rat called Biggoon. After managing to escape after some time, she returned and laid two eggs which hatched into strange furry creatures, so they were all banished and went to live in the mountains.[9]

The platypus is also used by some Aboriginal peoples as a totem, which is to them "a natural object, plant or animal that is inherited by members of a clan or family as their spiritual emblem", and the animal holds special meaning as a totem animal for the Wadi Wadi people, who live along the Murray River. Because of their cultural significance and importance in connection to country, the platypus is protected and conserved by these Indigenous peoples.[9]

The platypus has often been used as a symbol of Australia's cultural identity. In the 1940s, live platypuses were given to allies in the Second World War, in order to strengthen ties and boost morale.[9]

Platypuses have been used several times as mascots: Syd the platypus was one of the three mascots chosen for the Sydney 2000 summer Olympics along with an echidna and a kookaburra,[136] Expo Oz the platypus was the mascot for World Expo 88, which was held in Brisbane in 1988,[137] and Hexley the platypus is the mascot for the Darwin operating system, the BSD-based core of macOS and other operating systems from Apple Inc.[138]

Since the introduction of decimal currency to Australia in 1966, the embossed image of a platypus, designed and sculpted by Stuart Devlin, has appeared on the reverse (tails) side of the 20-cent coin.[139] The platypus has frequently appeared in Australian postage stamps, most recently the 2015 "Native Animals" series and the 2016 "Australian Animals Monotremes" series.[140][141]

In the American animated series Phineas and Ferb, the title characters own a pet bluish-green platypus named Perry who, unknown to them, is a secret agent. Such choices were inspired by media underuse, as well as to exploit the animal's striking appearance;[142] additionally, show creator Dan Povenmire, who also wrote the character's theme song, said that its opening lyrics are based on the introductory sentence of the Platypus article on Wikipedia, copying the "semiaquatic egg-laying mammal" phrase word for word and appending the phrase "of action";[143] however, the article did not include "egg-laying mammal" in the lead sentence until 2014, several years after the song released. As a character, Perry has been well received by both fans and critics.[144][145] Coincidentally, real platypuses show a similar cyan colour when seen under ultraviolet lighting.[146]

  • Platypus fur cape made in 1890, now in the National Gallery of Victoria
    Platypus fur cape made in 1890, now in the National Gallery of Victoria
  • Early 20th-century matchbox label
    Early 20th-century matchbox label
  • 9d postage stamp from 1937
    9d postage stamp from 1937

See also

[edit]

Footnotes

[edit]
  1. ^ The same root gives rise to platysma, a broad, wide and flat muscle of the neck.

Citations

[edit]
  1. ^ a b Woinarski, J.; Burbidge, A.A. (2016). "Ornithorhynchus anatinus". IUCN Red List of Threatened Species. 2016: e.T40488A21964009. doi:10.2305/IUCN.UK.2016-1.RLTS.T40488A21964009.en. Retrieved 19 November 2021.
  2. ^ "Ornithorhynchus anatinus". Global Biodiversity Information Facility. Retrieved 13 July 2021.
  3. ^ Pasitschniak-Arts, Maria; Marinelli, Lui (1 June 1998). "Ornithorhynchus anatinus". Mammalian Species (585): 1–9. doi:10.2307/3504433. JSTOR 3504433. Retrieved 15 October 2024.
  4. ^ Groves, C.P. (2005). "Order Monotremata". In Wilson, D.E.; Reeder, D.M (eds.). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press. p. 2. ISBN 978-0-8018-8221-0. OCLC 62265494.
  5. ^ a b c d e f Shaw, George; Nodder, Frederick Polydore (1799). "The Duck-Billed Platypus, Platypus anatinus". The Naturalist's Miscellany. 10 (CXVIII): 385–386. doi:10.5962/p.304567.
  6. ^ "Introduction to the Monotremata". University of California, Berkeley. Retrieved 21 September 2024.
  7. ^ "To Hunt, the Platypus Uses Its Electric Sixth Sense". American Museum of Natural History. 12 January 2018. Retrieved 21 September 2024.
  8. ^ a b "Platypus Conservation Initiative". University of New South Wales. Archived from the original on 19 May 2023. Retrieved 9 August 2023.
  9. ^ a b c d e f g h i j "A national assessment of the conservation status of the platypus". Australian Conservation Foundation. 23 November 2020. Archived from the original on 28 November 2020. Retrieved 28 November 2020.
  10. ^ "Platypus names (including "What's the plural of platypus?") - Australian Platypus Conservancy". platypus.asn.au. 6 March 2024. Retrieved 3 October 2024.
  11. ^ a b "Platypus | Wildlife Preservation Society of Queensland". Retrieved 3 October 2024.
  12. ^ M. Serena & G.A. Williams (2010). Conserving platypus and rat waters (PDF). Australian Platypus Conservancy.
  13. ^ a b "Platypus- WWF-Australia | Platypus | WWF Australia". wwf.org.au. Retrieved 3 October 2024.
  14. ^ "Platypus- WWF-Australia | Platypus | WWF Australia". wwf.org.au. Retrieved 3 October 2024.
  15. ^ "Platypus- WWF-Australia | Platypus | WWF Australia". wwf.org.au. Retrieved 3 October 2024.
  16. ^ "Platypus- WWF-Australia | Platypus | WWF Australia". wwf.org.au. Retrieved 3 October 2024.
  17. ^ "Platypus Out of the Water". 3 July 2017.
  18. ^ "Larila's Legacy". Hobart Rivulet Platypus. Retrieved 3 October 2024.
  19. ^ Hall, Brian K. (March 1999). "The Paradoxical Platypus". BioScience. 49 (3): 211–8. doi:10.2307/1313511. JSTOR 1313511.
  20. ^ a b "Duck-billed Platypus". Museum of hoaxes. Archived from the original on 29 July 2014. Retrieved 21 July 2010.
  21. ^ a b c d e f g "Platypus facts file". Australian Platypus Conservancy. Archived from the original on 10 November 2015. Retrieved 13 September 2006.
  22. ^ πλατύπους Archived 25 February 2021 at the Wayback Machine, Henry George Liddell, Robert Scott, A Greek-English Lexicon, on Perseus
  23. ^ πλατύς Archived 25 February 2021 at the Wayback Machine, A Greek-English Lexicon, on Perseus
  24. ^ πούς Archived 27 February 2021 at the Wayback Machine, A Greek-English Lexicon, on Perseus
  25. ^ Liddell, Henry George & Scott, Robert (1980). Greek-English Lexicon, Abridged Edition. Oxford University Press, Oxford, UK. ISBN 978-0-19-910207-5.
  26. ^ a b c d e f g h i j k l m n Grant, J.R. "16" (PDF). Fauna of Australia. Vol. 1b. Australian Biological Resources Study (ABRS). Archived from the original (PDF) on 19 May 2005. Retrieved 13 September 2006.
  27. ^ "Platypus Paradoxes". National Library of Australia. August 2001. Archived from the original on 5 March 2012. Retrieved 14 September 2006.
  28. ^ Liddell, Henry George; Scott, Robert (1940). "ὄρνις". A Greek-English Lexicon. Perseus Digital Library. Archived from the original on 4 April 2023. Retrieved 29 September 2022.
  29. ^ Liddell, Henry George; Scott, Robert (1940). "ῥύγχος". A Greek-English Lexicon. Perseus Digital Library. Archived from the original on 23 April 2023. Retrieved 29 September 2022.
  30. ^ Lewis, Charlton T.; Short, Charles (1879). "ănăs". A Latin Dictionary. Perseus Digital Library. Archived from the original on 27 September 2023. Retrieved 29 September 2022.
  31. ^ Bess, Anna. "ADW: Ornithorhynchidae: INFORMATION". Animaldiversity.org. Archived from the original on 17 January 2022. Retrieved 11 February 2022.
  32. ^ Collins, David. An Account of the English Colony in New South Wales, Volume 2. Retrieved 5 July 2017 – via Internet Archive.
  33. ^ Anich, Paula Spaeth (15 October 2020). "Biofluorescence in the platypus (Ornithorhynchus anatinus)". Mammalia. 85 (2): 179–181. doi:10.1515/mammalia-2020-0027.
  34. ^ "Platypus: Facts, Pictures: Animal Planet". Animal.discovery.com. 16 November 2011. Archived from the original on 27 July 2011. Retrieved 8 September 2012.
  35. ^ Guiler, E.R. (1983). "Tasmanian Devil". In R. Strahan (ed.). The Australian Museum Complete Book of Australian Mammals. Angus & Robertson. pp. 27–28. ISBN 978-0-207-14454-7.
  36. ^ Fish, F. E.; Frappell, P. B.; Baudinette, R. V.; Macfarlane, P. M. (15 February 2001). "Energetics of Terrestrial Locomotion of the Platypus Ornithorhynchus Anatinus". Journal of Experimental Biology. 204 (4): 797–803. doi:10.1242/jeb.204.4.797. hdl:2440/12192. PMID 11171362.
  37. ^ a b Munks, Sarah & Nicol, Stewart (May 1999). "Current research on the platypus, Ornithorhynchus anatinus in Tasmania: Abstracts from the 1999 'Tasmanian Platypus Workshop'". University of Tasmania. Archived from the original on 30 August 2006. Retrieved 23 October 2006.
  38. ^ "Thermal Biology of the Platypus". Davidson College. 1999. Archived from the original on 6 March 2012. Retrieved 14 September 2006.
  39. ^ Watson, Jm; Graves, Jam (1988). "Monotreme Cell-Cycles and the Evolution of Homeothermy". Australian Journal of Zoology. 36 (5): 573. doi:10.1071/ZO9880573.
  40. ^ Dawson, Tj; Grant, Tr; Fanning, D (1979). "Standard Metabolism of Monotremes and the Evolution of Homeothermy". Australian Journal of Zoology. 27 (4): 511. doi:10.1071/ZO9790511.
  41. ^ Graves, Jennifer (10 March 2006). "Sex Chromosome Specialization and Degeneration in Mammals". Cell. 124 (5): 901–914. doi:10.1016/j.cell.2006.02.024. PMID 16530039. S2CID 8379688.
  42. ^ Hayashi, S.; Houssaye, A.; Nakajima, Y.; Chiba, K.; Ando, T.; Sawamura, H.; Inuzuka, N.; Kaneko, N.; Osaki, T. (2013). "Bone Inner Structure Suggests Increasing Aquatic Adaptations in Desmostylia (Mammalia, Afrotheria)". PLOS ONE. 8 (4): e59146. Bibcode:2013PLoSO...859146H. doi:10.1371/journal.pone.0059146. PMC 3615000. PMID 23565143.
  43. ^ a b Piper, Ross (2007). Extraordinary Animals: An Encyclopedia of Curious and Unusual Animals. Greenwood Press. ISBN 978-0-313-33922-6.
  44. ^ Haeckel (1895). Systematische Phylogenie der Wirbelthiere (Vertebrata). Entwurf einer systematischen Stammesgeschichte (in German). Vol. 3 (1 ed.). Berlin: Georg Reimer. pp. 142–143. Archived from the original on 16 July 2021. Retrieved 16 July 2021.
  45. ^ Ungar, Peter S. (2010). "Monotremata and Marsupialia". Mammal Teeth: Origin, Evolution, and Diversity. The Johns Hopkins University Press. p. 130. ISBN 978-0-801-89668-2.
  46. ^ "Australian Fauna". Australian Fauna. Archived from the original on 29 May 2012. Retrieved 14 May 2010.
  47. ^ "Platypus venom linked to pain relief". University of Sydney. 8 May 2008. Archived from the original on 21 August 2011. Retrieved 14 May 2010.
  48. ^ "Platypus poison". Rainforest Australia. Archived from the original on 29 May 2010. Retrieved 14 May 2010.
  49. ^ a b c d Gerritsen, Vivienne Baillie (December 2002). "Platypus poison". Protein Spotlight (29). Archived from the original on 20 October 2008. Retrieved 14 September 2006.
  50. ^ Weimann, Anya (4 July 2007) Evolution of platypus venom revealed. Cosmos.
  51. ^ de Plater, G.M.; Milburn, P.J.; Martin, R.L. (2001). "Venom From the Platypus, Ornithorhynchus anatinus, Induces a Calcium-Dependent Current in Cultured Dorsal Root Ganglion Cells". Journal of Neurophysiology. 85 (3): 1340–5. doi:10.1152/jn.2001.85.3.1340. PMID 11248005. S2CID 2452708.
  52. ^ "The venom of the platypus (Ornithorhynchus anatinus)". Archived from the original on 1 February 2012. Retrieved 13 September 2006.
  53. ^ Jørn H. Hurum, Zhe-Xi Luo, and Zofia Kielan-Jaworowska, Were mammals originally venomous?, Acta Palaeontologica Polonica 51 (1), 2006: 1–11
  54. ^ a b c d Pettigrew, John D. (1999). "Electroreception in Monotremes" (PDF). The Journal of Experimental Biology. 202 (Part 10): 1447–54. doi:10.1242/jeb.202.10.1447. PMID 10210685. Archived (PDF) from the original on 28 September 2006. Retrieved 19 September 2006.
  55. ^ Czech-Damal, Nicole U.; Liebschner, Alexander; Miersch, Lars; Klauer, Gertrud; Hanke, Frederike D.; Marshall, Christopher; Dehnhardt, Guido; Hanke, Wolf (22 February 2012). "Electroreception in the Guiana dolphin (Sotalia guianensis)". Proceedings of the Royal Society B: Biological Sciences. 279 (1729): 663–668. doi:10.1098/rspb.2011.1127. PMC 3248726. PMID 21795271.
  56. ^ Proske, Uwe; Gregory, J. E.; Iggo, A. (1998). "Sensory receptors in monotremes". Philosophical Transactions of the Royal Society of London. 353 (1372): 1187–1198. doi:10.1098/rstb.1998.0275. PMC 1692308. PMID 9720114.
  57. ^ a b c Warren, Wesley C.; et al. (8 May 2008). "Genome analysis of the platypus reveals unique signatures of evolution". Nature. 453 (7192): 175–183. Bibcode:2008Natur.453..175W. doi:10.1038/nature06936. PMC 2803040. PMID 18464734.
  58. ^ Gregory, J.E.; Iggo, A.; McIntyre, A.K.; Proske, U. (June 1988). "Receptors in the Bill of the Platypus". Journal of Physiology. 400 (1): 349–366. doi:10.1113/jphysiol.1988.sp017124. PMC 1191811. PMID 3418529.
  59. ^ Manning, A.; Dawkins, M.S. (1998). An Introduction to Animal Behaviour (5th ed.). Cambridge University Press.
  60. ^ a b Pettigrew, John D.; Manger, P. R.; Fine, S. L. (1998). "The sensory world of the platypus". Philosophical Transactions of the Royal Society of London. 353 (1372): 1199–1210. doi:10.1098/rstb.1998.0276. PMC 1692312. PMID 9720115.
  61. ^ Dawkins, Richard (2004). "The Duckbill's Tale". The Ancestor's Tale, A Pilgrimage to the Dawn of Life. Boston, Massachusetts: Houghton Mifflin. ISBN 978-0-618-00583-3.
  62. ^ a b Masakazu Asahara; Masahiro Koizumi; Thomas E. Macrini; Suzanne J. Hand; Michael Archer (2016). "Comparative cranial morphology in living and extinct platypuses: Feeding behavior, electroreception, and loss of teeth". Science Advances. 2 (10): e1601329. doi:10.1126/sciadv.1601329.
  63. ^ Zeiss, Caroline; Schwab, Ivan R.; Murphy, Christopher J.; Dubielzig, Richard W. (2011). "Comparative retinal morphology of the platypus". Journal of Morphology. 272 (8): 949–57. doi:10.1002/jmor.10959. PMID 21567446. S2CID 28546474.
  64. ^ November 2020, Mindy Weisberger-Senior Writer 02 (2 November 2020). "Platypuses glow an eerie blue-green under UV light". livescience.com. Archived from the original on 5 November 2020. Retrieved 7 November 2020.{{cite web}}: CS1 maint: numeric names: authors list (link)
  65. ^ "Platypus". Department of Primary Industries and Water, Tasmania. 31 August 2006. Archived from the original on 9 October 2006. Retrieved 12 October 2006.
  66. ^ a b Sutton, Malcolm (3 May 2017). "Platypus 'sighting' in the Adelaide Hills sparks camera set-up to capture extinct species - ABC News". ABC (Australian Broadcasting Corporation). Archived from the original on 26 November 2020. Retrieved 12 October 2020.
  67. ^ Keogh, Melissa (3 October 2018). "Life reinstated to much-loved Warrawong Wildlife Sanctuary". The Lead SA. Archived from the original on 12 October 2020. Retrieved 12 October 2020.
  68. ^ Adams, Prue (27 March 2005). "Wamsley walks away from Earth Sanctuaries". Landline. Australian Broadcasting Corporation. Archived from the original on 12 October 2020. Retrieved 12 October 2020.
  69. ^ Sutton, Malcolm (1 October 2020). "V6 Commodore water pump gets the tick from nesting platypus at Warrawong". ABC News. Australian Broadcasting Corporation. Archived from the original on 7 October 2020. Retrieved 7 October 2020.
  70. ^ "Research on Kangaroo Island". University of Adelaide. 4 July 2006. Archived from the original on 6 July 2004. Retrieved 23 October 2006.
  71. ^ "Find out how platypuses are faring on Kangaroo Island following the bushfires". Department for Environment and Water. 7 April 2020. Archived from the original on 21 July 2021. Retrieved 12 October 2020.
  72. ^ a b Scott, Anthony; Grant, Tom (November 1997). "Impacts of water management in the Murray-Darling Basin on the platypus (Ornithorhynchus anatinus) and the water rat (Hydromus chrysogaster)" (PDF). CSIRO Australia. Archived (PDF) from the original on 15 March 2016. Retrieved 23 October 2006.
  73. ^ "Platypus burrows". Australian Platypus Conservancy. 6 March 2024.
  74. ^ "Platypus in Country Areas". Australian Platypus Conservancy. Archived from the original on 17 September 2016. Retrieved 23 October 2006.
  75. ^ Peter de Kruijff (14 February 2024). "Oldest-known wild platypus gives new insights into longevity of enigmatic Australian species". ABC Science.
  76. ^ a b c d "Platypus". Environmental Protection Agency/Queensland Parks and Wildlife Service. 2006. Archived from the original on 21 October 2009. Retrieved 24 July 2009.
  77. ^ a b c Cromer, Erica (14 April 2004). "Monotreme Reproductive Biology and Behavior". Iowa State University. Archived from the original on 13 March 2009. Retrieved 18 June 2009.
  78. ^ a b c Grant, T.G.; Temple-Smith, P.D. (1998). "Field biology of the platypus (Ornithorhynchus anatinus): historical and current perspectives". Philosophical Transactions: Biological Sciences. 353 (1372): 1081–91. doi:10.1098/rstb.1998.0267. PMC 1692311. PMID 9720106.
  79. ^ Gardner, J. L.; Serena, M. (1995). "Spatial-Organization and Movement Patterns of Adult Male Platypus, Ornithorhynchus anatinus (Monotremata, Ornithorhynchidae)". Australian Journal of Zoology. 43 (1): 91–103. doi:10.1071/ZO9950091.
  80. ^ a b c "Platypus in Tasmania | Department of Primary Industries, Parks, Water and Environment, Tasmania". dpipwe.tas.gov.au. Archived from the original on 8 March 2020. Retrieved 10 April 2020.
  81. ^ Fish, F.E.; Baudinette, R.V.; Frappell, P.B.; Sarre, M.P. (1997). "Energetics of Swimming by the Platypus Ornithorhynchus anatinus: Metabolic Effort Associated with Rowing" (PDF). The Journal of Experimental Biology. 200 (20): 2647–52. doi:10.1242/jeb.200.20.2647. PMID 9359371. Archived (PDF) from the original on 26 September 2009. Retrieved 23 October 2006.
  82. ^ a b Philip Bethge (April 2002). Energetics and foraging behaviour of the platypus (thesis). University of Tasmania. doi:10.25959/23210588.v1. Archived from the original on 25 October 2018. Retrieved 21 June 2009.
  83. ^ Kruuk, H. (1993). "The Diving Behaviour of the Platypus (Ornithorhynchus anatinus) in Waters with Different Trophic Status". The Journal of Applied Ecology. 30 (4): 592–8. Bibcode:1993JApEc..30..592K. doi:10.2307/2404239. JSTOR 2404239.
  84. ^ Holland, Jennifer S. (July 2011). "40 Winks?". National Geographic. 220 (1).
  85. ^ a b Grant, T. R.; Griffiths, M.; Leckie, R.M.C. (1983). "Aspects of Lactation in the Platypus, Ornithorhynchus anatinus (Monotremata), in Waters of Eastern New South Wales". Australian Journal of Zoology. 31 (6): 881–9. doi:10.1071/ZO9830881.
  86. ^ Grant, Tom (2 October 2007). Platypus. Csiro Publishing. ISBN 978-0-643-10127-2.
  87. ^ Anna Bess Sorin & Phil Myers (2001). "Family Ornithorhynchidae (platypus)". University of Michigan Museum of Zoology. Archived from the original on 10 April 2011. Retrieved 24 October 2006.
  88. ^ Vogelnest, Larry; Woods, Rupert (18 August 2008). Medicine of Australian Mammals. Csiro Publishing. ISBN 978-0-643-09797-1. Archived from the original on 25 May 2024. Retrieved 27 April 2024.
  89. ^ Hughes, R. L.; Hall, L. S. (28 July 1998). "Early development and embryology of the platypus". Philosophical Transactions of the Royal Society B: Biological Sciences. 353 (1372): 1101–14. doi:10.1098/rstb.1998.0269. PMC 1692305. PMID 9720108.
  90. ^ a b Manger, Paul R.; Hall, Leslie S.; Pettigrew, John D. (29 July 1998). "The development of the external features of the platypus (Ornithorhynchus anatinus)". Philosophical Transactions: Biological Sciences. 353 (1372): 1115–25. doi:10.1098/rstb.1998.0270. PMC 1692310. PMID 9720109.
  91. ^ "Ockhams Razor". The Puzzling Platypus. 20 July 2001. Archived from the original on 9 August 2017. Retrieved 2 December 2006.
  92. ^ Myers, P. Z. (2008). "Interpreting Shared Characteristics: The Platypus Genome". Nature Education. 1 (1): 462008. Archived from the original on 4 March 2018. Retrieved 26 March 2015.
  93. ^ Stannard, Hayley J.; Old, Julie M. (2023). "Wallaby joeys and platypus puggles are tiny and undeveloped when born. But their mother's milk is near-magical". The Conversation. Archived from the original on 10 November 2023. Retrieved 25 October 2023.
  94. ^ Stannard, Hayley J.; Miller, Robert D.; Old, Julie M. (2020). "Marsupial and monotreme milk – a review of its nutrients and immune properties". PeerJ. 8: e9335. doi:10.7717/peerj.9335. PMC 7319036. PMID 32612884.
  95. ^ "Egg-laying mammals" (PDF). Queensland Museum. November 2000. Archived from the original (PDF) on 22 July 2008. Retrieved 19 June 2009.
  96. ^ Lecointre, Guillaume; Le Guyader, Hervé (2006). The Tree of Life: A Phylogenetic Classification. Harvard University Press. ISBN 978-0-674-02183-9. Retrieved 28 March 2015.
  97. ^ a b c Kirsch, John A. W.; Mayer, Gregory C. (29 July 1998). "The platypus is not a rodent: DNA hybridization, amniote phylogeny and the palimpsest theory". Philosophical Transactions: Biological Sciences. 353 (1372): 1221–37. doi:10.1098/rstb.1998.0278. PMC 1692306. PMID 9720117.
  98. ^ a b Rauhut, O.W.M.; Martin, T.; Ortiz-Jaureguizar, E.; Puerta, P. (2002). "The first Jurassic mammal from South America". Nature. 416 (6877): 165–8. Bibcode:2002Natur.416..165R. doi:10.1038/416165a. hdl:11336/99461. PMID 11894091. S2CID 4346804.
  99. ^ Messer, M.; Weiss, A.S.; Shaw, D.C.; Westerman, M. (March 1998). "Evolution of the Monotremes: Phylogenetic Relationship to Marsupials and Eutherians, and Estimation of Divergence Dates Based on α-Lactalbumin Amino Acid Sequences". Journal of Mammalian Evolution. 5 (1): 95–105. doi:10.1023/A:1020523120739. S2CID 39638466.
  100. ^ Phillips MJ; Bennett TH; Lee MS (2009). "Molecules, morphology, and ecology indicate a recent, amphibious ancestry for echidnas". Proc. Natl. Acad. Sci. U.S.A. 106 (40): 17089–94. Bibcode:2009PNAS..10617089P. doi:10.1073/pnas.0904649106. PMC 2761324. PMID 19805098.
  101. ^ Musser, A.M. (2006). "26. Furry Egg-layers: Monotreme Relationships and Radiations". In Merrick, J.R.; Archer, M.; Hickey, G.M.; Lee, M.S.Y. (eds.). Evolution and Biogeography of Australasian Vertebrates. Auscipub. pp. 523–550. ISBN 978-0975779002.
  102. ^ a b Rich, Thomas H.; Hopson, James A.; Gill, Pamela G.; Trusler, Peter; Rogers-Davidson, Sally; Morton, Steve; Cifelli, Richard L.; Pickering, David; Kool, Lesley (2016). "The mandible and dentition of the Early Cretaceous monotreme Teinolophos trusleri". Alcheringa: An Australasian Journal of Palaeontology. 40 (4): 475–501. Bibcode:2016Alch...40..475R. doi:10.1080/03115518.2016.1180034. hdl:1885/112071. S2CID 89034974.
  103. ^ a b Pascual, R.; Goin, F.J.; Balarino, L.; Udrizar Sauthier, D.E. (2002). "New data on the Paleocene monotreme Monotrematum sudamericanum, and the convergent evolution of triangulate molars" (PDF). Acta Palaeontologica Polonica. 47 (3): 487–492. Archived (PDF) from the original on 9 August 2017. Retrieved 18 March 2009.
  104. ^ a b c d Flannery, Timothy F.; McCurry, Matthew R.; Rich, Thomas H.; Vickers-Rich, Patricia; Smith, Elizabeth T.; Helgen, Kristofer M. (2 April 2024). "A diverse assemblage of monotremes (Monotremata) from the Cenomanian Lightning Ridge fauna of New South Wales, Australia". Alcheringa: An Australasian Journal of Palaeontology. 48 (2): 319–337. Bibcode:2024Alch...48..319F. doi:10.1080/03115518.2024.2348753.
  105. ^ Folger, Tim (1993). "A platypus in Patagonia (Ancient life – 1992)". Discover. 14 (1): 66.
  106. ^ Mihai, Andrei (2013). "'Platypus-zilla' fossil unearthed in Australia". ZME Science. Archived from the original on 21 July 2021. Retrieved 5 November 2013.
  107. ^ Selim, Jocelyn (25 April 2005). "Sex, Ys, and Platypuses". Discover. Archived from the original on 16 May 2008. Retrieved 7 May 2008.
  108. ^ Frank Grützner; Willem Rens; Enkhjargal Tsend-Ayush; Nisrine El-Mogharbel; Patricia C. M. O'Brien; Russell C. Jones; Malcolm A. Ferguson-Smith; Jennifer A. Marshall Graves (16 December 2004). "In the platypus a meiotic chain of ten sex chromosomes shares genes with the bird Z and mammal X chromosomes". Nature. 432 (7019): 913–917. Bibcode:2004Natur.432..913G. doi:10.1038/nature03021. PMID 15502814. S2CID 4379897.
  109. ^ "Beyond the Platypus Genome – 2008 Boden Research Conference". Reprod Fertil Dev. 21 (8): i–ix, 935–1027. 2009. Archived from the original on 21 November 2015. Retrieved 3 March 2012.
  110. ^ Cortez, Diego; Marin, Ray; Toledo-Flores, Deborah; Froidevaux, Laure; Liechti, Angélica; Waters, Paul D.; Grützner, Frank; Kaessmann, Henrik (2014). "Origins and functional evolution of Y chromosomes across mammals". Nature. 508 (7497): 488–493. Bibcode:2014Natur.508..488C. doi:10.1038/nature13151. PMID 24759410. S2CID 4462870.
  111. ^ Salleh, Anna (5 May 2014). "Platypus Sex 'Master Switch' Identified". Australian Broadcasting Corporation. Archived from the original on 6 July 2016. Retrieved 5 June 2014.
  112. ^ Zhou, Yang; Shearwin-Whyatt, Linda; Li, Jing; Song, Zhenzhen; Hayakawa, Takashi; Stevens, David; Fenelon, Jane C.; Peel, Emma; Cheng, Yuanyuan; Pajpach, Filip; Bradley, Natasha; Suzuki, Hikoyu; Nikaido, Masato; Damas, Joana; Daish, Tasman; Perry, Tahlia; Zhu, Zexian; Geng, Yuncong; Rhie, Arang; Sims, Ying; Wood, Jonathan; Haase, Bettina; Mountcastle, Jacquelyn; Fedrigo, Olivier; Li, Qiye; Yang, Huanming; Wang, Jian; Johnston, Stephen D.; Phillippy, Adam M.; Howe, Kerstin; Jarvis, Erich D.; Ryder, Oliver A.; Kaessmann, Henrik; Donnelly, Peter; Korlach, Jonas; Lewin, Harris A.; Graves, Jennifer; Belov, Katherine; Renfree, Marilyn B.; Grutzner, Frank; Zhou, Qi; Zhang, Guojie (29 April 2021). "Platypus and echidna genomes reveal mammalian biology and evolution". Nature. 592 (7856): 756–762. Bibcode:2021Natur.592..756Z. doi:10.1038/s41586-020-03039-0. PMC 8081666. PMID 33408411.
  113. ^ "Game Act 1890". Australasian Legal Information Institute. 10 July 1890. Archived from the original on 9 August 2023. Retrieved 9 August 2023.
  114. ^ John Woinarski (Natural Resources, Environment and The Arts; Group), Andrew Burbidge (IUCN SSC Australasian Marsupial and Monotreme Specialist (22 April 2014). "IUCN Red List of Threatened Species: Ornithorhynchus anatinus". IUCN Red List of Threatened Species. Archived from the original on 4 March 2020. Retrieved 3 December 2020.
  115. ^ "Platypus Risk Assessment" (PDF). Department of Energy, Environment and Climate Action. Archived (PDF) from the original on 27 March 2023. Retrieved 9 August 2023.
  116. ^ Stannard HJ, Wolfenden J, Old JM (2010). Evaluating the capacity of constructed wetlands in sustaining a captive population of platypus (Ornithorhynchus anatinus). Australasian Journal of Environmental Management. 17(1), 27-34. DOI: 10.1080/14486563.2010.9725246
  117. ^ a b c Wilcox, Christie (29 August 2019). "The silent decline of the platypus, Australia's beloved oddity". National Geographic. Archived from the original on 12 October 2020. Retrieved 12 October 2020.
  118. ^ "EPBC Act List of Threatened Fauna". Species Profile and Threats Database. Australian Government. Department of Agriculture, Water and the Environment. Archived from the original on 5 November 2020. Retrieved 12 October 2020.
  119. ^ University of New South Wales (21 January 2020). "Platypus on brink of extinction". EurekAlert!. Archived from the original on 13 May 2020. Retrieved 22 January 2020.
  120. ^ "Platypus on brink of extinction". ScienceDaily (Press release). University of New South Wales. 21 January 2020.
  121. ^ Bino, Gilad; Kingsford, Richard T.; Wintle, Brendan A. (February 2020). "A stitch in time – Synergistic impacts to platypus metapopulation extinction risk". Biological Conservation. 242: 108399. Bibcode:2020BCons.24208399B. doi:10.1016/j.biocon.2019.108399.
  122. ^ Cox, Lisa (23 November 2020). "Australia's platypus habitat has shrunk 22% in 30 years, report says". the Guardian. Archived from the original on 28 November 2020. Retrieved 28 November 2020.
  123. ^ "Platypus should be listed as a threatened species: new report". UNSW Newsroom. University of New South Wales. 23 November 2020. Archived from the original on 26 November 2020. Retrieved 28 November 2020.
  124. ^ "Platypus Fungal Disease". Department of Primary Industries and Water, Tasmania. 29 August 2008. Archived from the original on 7 March 2008. Retrieved 29 February 2008.
  125. ^ "Fantastic Fleay turns 20!". Zoos Victoria. 31 October 2013. Archived from the original on 9 November 2018. Retrieved 4 February 2014.
  126. ^ "David Fleay's achievements". Queensland Government. 23 November 2003. Archived from the original on 2 October 2006. Retrieved 13 September 2006.
  127. ^ a b "Platypus". Catalyst. 13 November 2003. Archived from the original on 23 July 2011. Retrieved 13 September 2006.
  128. ^ "Pitter patter – Platypus twins!". Zoo Victoria. 4 March 2013. Archived from the original on 28 August 2018. Retrieved 17 August 2017.
  129. ^ "Zoos". Australian Platypus Conservancy. 22 November 2016. Archived from the original on 4 March 2019. Retrieved 17 August 2017.
  130. ^ Anderson, Erik (22 November 2019). "Rare Platypus On Display At San Diego Zoo Safari Park". KPBS Public Media. Archived from the original on 13 May 2020. Retrieved 29 December 2019. The animals are the only platypuses on display outside of their native country.
  131. ^ "Platypus | San Diego Zoo Animals & Plants". animals.sandiegozoo.org. Archived from the original on 25 July 2020. Retrieved 29 December 2019.
  132. ^ "Animals: End of the Affair". Time. 19 August 1957. Archived from the original on 16 June 2007.
  133. ^ Lee S. Crandall (1964). The Management of Wild Mammals in Captivity. University of Chicago Press.
  134. ^ "Protecting Wild Animals". The Advertiser (Adelaide). 27 September 1912. Archived from the original on 9 August 2023. Retrieved 9 August 2023.
  135. ^ a b McKay, Helen F.; McLeod, Pauline E.; Jones, Francis F.; Barber, June E. (2001). Gadi Mirrabooka: Australian Aboriginal Tales from the Dreaming. Libraries Unlimited. ISBN 978-1563089237.
  136. ^ "A Brief History of the Olympic and Paralympic Mascots". Beijing2008. 5 August 2004. Archived from the original on 21 June 2008. Retrieved 25 October 2006.
  137. ^ "About World Expo '88". Foundation Expo '88. 1988. Archived from the original on 19 December 2013. Retrieved 17 December 2007.
  138. ^ "The Home of Hexley the Platypus". Archived from the original on 13 February 2011. Retrieved 25 October 2006.
  139. ^ "Circulating coins: Twenty Cents". Royal Australian Mint. 8 January 2016. Archived from the original on 19 March 2021. Retrieved 12 September 2020.
  140. ^ "Native Animals - Issue Date 13 January 2015". Australia Post Collectables. Archived from the original on 25 January 2021. Retrieved 12 September 2020.
  141. ^ "Australian Animals Monotremes – Issue Date 26 September 2016". Australia Post Collectables. Archived from the original on 26 January 2021. Retrieved 12 September 2020.
  142. ^ "Disney gives 'Ferb' pickup, major push – Q&A: Dan Povenmire". The Hollywood Reporter. 7 June 2009. Archived from the original on 20 June 2018. Retrieved 5 March 2017.
  143. ^ "Perry the Platypus" Live at Musi-Cal, 9 August 2016, archived from the original on 2 January 2021, retrieved 23 March 2021
  144. ^ Littleton, Cynthia (20 November 2009). "'Phineas' star Perry makes mark on auds". Variety. Archived from the original on 2 December 2009. Retrieved 26 November 2009.
  145. ^ Jackson, John (31 March 2009). "Five Reasons Why Phineas and Ferb is the Best Kids Show on TV". Paste. Archived from the original on 3 October 2019. Retrieved 25 November 2009.
  146. ^ Anich, Paula Spaeth; Anthony, Sharon; Carlson, Michaela; Gunnelson, Adam; Kohler, Allison M.; Martin, Jonathan G.; Olson, Erik R. (26 March 2021). "Biofluorescence in the platypus (Ornithorhynchus anatinus)". Mammalia. 85 (2): 179–181. doi:10.1515/mammalia-2020-0027.

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