60 Fun Facts About Platypus

The platypus is one of only five living species in which group of egg-laying mammals?

The other four are all echidnas; every other mammal on Earth gives birth to live young.

Which other animals are the only egg-laying mammals alive alongside the platypus?

There are four echidna species; molecular clocks suggest the platypus split from them roughly 19-48 million years ago.

What did the first scientists to examine a preserved platypus in 1799 conclude?

George Shaw literally took scissors to the pelt looking for stitches; Robert Knox suspected Chinese sailors had made it.

Which sense do platypuses use to find prey with their eyes, ears and nostrils shut underwater?

About 40,000 electroreceptors in the bill pick up the tiny currents made by a shrimp's muscles; they will even attack an 'artificial shrimp' carrying a current.

Where is the male platypus's venomous spur located?

Both sexes are born with the ankle spurs, but only males keep them into adulthood and use them fighting rivals in the breeding season.

The common name 'platypus' comes from Greek words meaning what?

By those Greek roots the correct plural would be 'platypodes'; 'platypi' is pseudo-Latin.

Why was George Shaw's original genus name Platypus dropped in favour of Ornithorhynchus?

Johann Blumenbach independently described the animal as Ornithorhynchus paradoxus in 1800, and that genus name stuck.

The scientific name Ornithorhynchus anatinus literally means what?

Ornith- is 'bird', rhynchos is 'snout' and anatinus is Latin for 'duck-like'.

What unofficial name is used for a baby platypus?

'Platypup' is also used unofficially; there is no formal term.

What colour does platypus fur glow under ultraviolet light?

The biofluorescence may hide it from UV-sensitive predators in low light; it is also the only mammal known to have hollow hair-pigment melanosomes.

Which mammals are the only ones more densely furred than the platypus?

The waterproof coat traps a layer of air that keeps the animal warm in and out of water.

How does the platypus's tail differ from a beaver's?

The tail stores fat reserves and works as a rudder; Aboriginal hunters prized it as the fattiest, most nutritious part.

How does a platypus protect its front webbing when walking on land?

Webbing is more extensive on the front feet, which do all the propulsion when swimming.

Adult platypuses have no teeth. What do they use to grind food instead?

Young platypuses do have a few molars but lose them around the time they leave the burrow.

Which internal organ does the platypus lack a functional version of?

It is missing the genes needed to make pepsin, the stomach's protein-digesting enzyme.

What is the platypus's average body temperature?

That is a full five degrees below the placental-mammal norm, and it can keep feeding in water below 5 °C.

Roughly how much does an average male platypus weigh?

About 50 cm long; females are noticeably smaller at around 900 g, and animals get bigger the further south you go.

Besides the platypus and its egg-laying cousins, which is the only mammal known to have electroreception?

The platypus's brain map is dominated by its bill in the same way a human's is dominated by the hands.

Roughly how many electroreceptors are arranged in the skin of a platypus's bill?

Cortical cells receive input from both electro- and touch receptors, so the platypus may literally feel electric fields as touches.

How long can the pain from a platypus sting last in humans?

The venom, made largely of defensin-like proteins, causes swelling and then a heightened sensitivity to pain called hyperalgesia.

Where in the male platypus's body is its venom produced?

The kidney-shaped glands connect to the ankle spur; the spurs are weapons in fights between males over mates.

On which Australian island was a platypus population introduced in the 1920s?

About 150 lived in the Rocky River area of Flinders Chase National Park before the 2019-20 bushfires tore through it.

What is unique about the platypus's swimming style among mammals?

The webbed hind feet and tail are used only for steering; dives average about 35 seconds.

In one study, how long did platypus dives last on average?

Surfacing intervals averaged just 13 seconds between dives.

What is the longest a platypus has survived in captivity?

Wild animals have been recaptured at 24 years old, remarkable for something the size of a small cat.

Which fish is among the platypus's natural predators?

Goannas, carpet snakes, eagles, saltwater crocodiles and red foxes also take them.

Who confirmed in 1884 that the female platypus really does lay eggs?

Early European naturalists refused to believe it; the same Caldwell later described the uterine development of the koala.

How many eggs does a female platypus normally lay?

They are small and leathery, about 17 mm long, and hatch after roughly ten days of external incubation.

How long is a platypus egg incubated outside the mother's body?

The eggs first develop inside her for around 28 days; she then curls around them in the burrow.

How does a mother platypus deliver milk to her young, given she has no teats?

The young lap the milk from her fur; it is thicker than placental-mammal milk.

How long can a platypus nesting burrow be?

The mother plugs the tunnel with thin soil walls; squeezing past them wrings the water from her fur and keeps the nest dry.

For roughly how long are young platypuses milk-fed before emerging from the burrow?

By then they are fully furred and about two-thirds of adult weight.

How many sex chromosomes does the platypus have, compared with two in most mammals?

Males are X1Y1X2Y2X3Y3X4Y4X5Y5, and one platypus X is closely related to the bird Z chromosome.

Which large semiaquatic rodent is thought to have outcompeted the platypus for hard prey, driving its tooth loss around 2.5 million years ago?

The rakali, or Australian water-rat, arrived from New Guinea; the platypus specialised on soft-bodied prey it did not have to fight over.

The largest platypus known, Obdurodon tharalkooschild, was about how long?

It is known from a single fossilised tooth dated to 5-15 million years ago.

Fossil platypus relatives Monotrematum and Patagorhynchus have been found on which continent?

They reached Argentina when Australia and South America were still joined via Antarctica.

How did the IUCN categorise the platypus in its 2016 assessment?

The 2016 listing assumed a 30% decline since European settlement; some biologists think it may be closer to 50%.

The platypus has been legally protected in every state where it lives since which year?

Victoria led the way in 1890; the fur trade had been killing them since the late 19th century.

Which type of yabby trap is banned in several states because it drowns platypuses?

They are banned in the ACT, South Australia, Tasmania and Victoria and restricted in NSW and Queensland.

As of 2019, the only platypuses in captivity outside Australia were at which zoo?

The Bronx Zoo received three in 1947; one female, Penelope, had a false pregnancy.

Where was the first successful captive breeding of platypuses achieved, in 1943?

David Fleay managed it in Victoria; Healesville later bred twins between 2008 and 2012.

During World War II, a live platypus sent as a gift to which leader died en route?

Australia gave platypuses as diplomatic gifts despite an export ban; this one may have been killed by shock from depth charges dropped after a U-boat encounter.

In an upper Darling River Dreamtime story, the first platypuses hatched from a duck kidnapped by which creature?

Some Aboriginal peoples saw the platypus as a duck-water rat hybrid; in another tale it refuses to join the birds, land animals or water animals.

The platypus was a mascot at which Olympic Games?

'Syd' the platypus shared duties with Olly the kookaburra and Millie the echidna.

Stuart Devlin's platypus design has appeared since 1966 on which Australian coin?

Collectors hunt for varieties in the number and length of the platypus's claws caused by die-stamping errors.

Perry the Platypus, secret agent, is a character in which animated series?

Codenamed Agent P, he battles Dr Doofenshmirtz in the B-plot of every episode; his only sound, a beak rattle, is voiced by Dee Bradley Baker.

Who sent the first platypus pelt and sketch back to Britain in 1798?

British scientists' first hunch was that the whole thing was a hoax.

Which early nickname did European settlers NOT commonly use for the platypus?

The 'mole' names came from its burrowing habit and dense fur.

The platypus's shoulder girdle contains an interclavicle, a bone it shares with which group?

Its bones are also unusually dense (osteosclerosis), which cuts buoyancy for diving.

Which type of prey does the platypus store in its cheek pouches to eat later?

It is a carnivore that probes the stream bottom with its bill, then surfaces to chew what it has collected.

How does the male platypus grip the female during mating?

He then positions his own tail under her from the side and grips her neck or shoulder.

Where was the last confirmed sighting of a wild platypus on the South Australian mainland, in 1975?

It was thought extinct there until a nesting platypus was filmed at the reopened Warrawong Sanctuary in October 2020.

How did George Shaw check whether the first platypus specimen had been stitched together?

Robert Knox suspected Chinese sailors had made it, since the specimen reached England via the Indian Ocean.

Going strictly by the Greek roots, what would the plural of 'platypus' be?

Dictionaries list 'platypuses' or simply 'platypus'; 'platypi' is pseudo-Latin.

Which German naturalist independently described the platypus as Ornithorhynchus paradoxus in 1800?

He worked from a specimen given to him by Sir Joseph Banks; priority rules settled on Ornithorhynchus anatinus.

The platypus follows Bergmann's rule, meaning individuals get larger the farther they live in which direction?

Colder climates favour larger bodies; an average male measures 50 cm and weighs 1.7 kg.

What is the oldest age at which a wild platypus has been recaptured?

Captive platypuses have lived up to thirty years.

Which Australian state was the first to give the platypus legal protection, in 1890?

Protection extended across Australia by 1912, though the animals still drown in inland fishing nets.

In which journal was the draft platypus genome published in May 2008?

It revealed reptilian and mammalian elements plus two genes previously seen only in non-mammalian vertebrates.

Lacking the mammalian SRY gene, the platypus determines sex using which gene on its oldest Y chromosome?

One of its X chromosomes closely resembles the bird Z chromosome.