ornithorrinc (Ornithorhynchus anatinus) also know as duck-billed platypus, is an aquatic animal native to Australia (East) and Trasmania. The platypus is an extremely rare animal in every way, not only because of its appearance, but also because it belongs to one of the five species known as monotremes, named after mammals that lay eggs, instead of giving birth to live young . The other four species belong to the echidnas.


The platypus is the only representative of its family (Ornithorhynchidae) and genus (Ornithorhynchus). Although several related species have been found in the fossil record. The first scientists to come across the animal in 1793 described it as "several animals sewn together."


The platypus has an extremely strange appearance, as it has otter legs, duckbill and beaver tail. Its hind legs are also webbed like those of a water bird.

Weight varies markedly between different individuals from 0,7 to 2,4 kg. When it comes to size, the male is larger than the female with an average of 50 cm in length. The females measure an average of 43 cm and varies according to the region where they live. It does not follow any particular weather rules and it is not known for sure why but it is suspected that it may be due to environmental factors such as predation and human encroachment.

Both the body and the broad tail are covered in dense brown fur that gives the animal an insulating layer that keeps it warm. It is also waterproof and its texture is similar to that of a mole. The tail is used as a fat store (a characteristic shared with the Tasmanian devil). The webs of your feet are most important in the front feet and bend backwards when walking on the surface of the ground. The elongated muzzle and lower jaw are covered by soft fur, thus forming the beak. On the dorsal surface of the horn are the nostrils, while the eyes and ears are located in a groove located just behind the muzzle. The groove is able to close when swimming. When disturbed they emit a low growl and in captivity various vocalizations have been detected for different situations.

Normally the body temperature in placental mammals is about 37 ° C, but in the platypus there is a variation and its body averages about 32 ° C. The researchers believe that it is due to an adaptation to the environment that surrounds them, rather than a historical characteristic of monotremes.

The young platypuses have three teeth in each of their jaws (one premolar and two molars) and teeth (three molars), which they lose before or after leaving the burrow for the first time. Adults have heavily keratinized pads instead of teeth.

When it comes to walking, its pace is similar to that of a reptile. Her legs are on the sides of her body instead of below. When walking on land, you walk with your knuckles on your front feet to protect the straps between your toes.


One of the most unknown characteristics of the platypus is its dangerousness, since it has spurs that release venom located on its back foot. Despite the fact that both female and male have spurs, only the male generates the poison. This poison is used for self-defense and to cause lysis of bacteria and fungi, although it is enough to kill small animals such as dogs, and although the poisonous is not deadly to humans, it is enough to cause great pain and can even incapacitate it.

When the venom is administered, an edema is generated that develops rapidly around the wound and spreads throughout the affected part. Information obtained from medical records indicates that pain develops into long-term hyperalgesia (increased sensitivity to pain) that persists for days or even months.

The venom is developed in the femoral glands which are kidney-shaped alveolar glands connected by a thin-walled conduit to a calcaneal spur on each hind limb. The female has rudimentary buds that do not develop (they fall before the end of their first year) and lack functional crural glands.

The amount of the venom increases during the breeding season to be used in the bifurcates with other males. Although it is not life threatening, it does leave the victim with serious damage.




It is a monotreme mammal that is the only one capable of detecting the electric fields produced by its prey generated by its muscular contractions. The electroreception of the platypus is the most sensitive of all monotrems.

Electroreceptors are found in face-to-tail rows on the skin of the beak, while mechanoreceptors (used to detect touch) are evenly distributed throughout the beak. In this way, it is able to determine the direction of the electrical sources that it perceives, comparing the differences between the signal intensities through the electroreceptor sheet. This explains the side-to-side head movement it makes when hunting, which is also seen in the hammerhead shark. The coincidence of the tactile and electrosensory inputs suggests a mechanism that determines the distance of the prey that, when moving, emit both electrical signals and mechanical pressure pulses. The platypus uses the difference between the arrival times of the two signals to detect how far away its prey is.

Electroreceptors also allow you to detect animate and inanimate objects by closing your eyes, ears and nose when submerged.


Most of its life is spent in the water in search of fresh food, but it is also possible to see it on land quite frequently. Specifically, it usually spends about 12 hours a day hunting in the water and the rest of the time (outside the mating season) is spent in a burrow about 30 cm deep.


The platypus is an animal that has a semi-aquatic life, therefore it can be found in streams and rivers in the highest latitudes of Australia (East) and Tasmania. It is also possible to locate it in tropical jungles.

Platypus swimming

Platypus swimming


The platypus is a carnivorous animal that feeds on annelid worms, annelid larvae, insect larvae, freshwater shrimp, and freshwater yabby. It hunts them while swimming or takes them out of hiding by digging in the river bed with its snout when it detects them with its electroreceptors. He spends about 12 hours a day looking for food because he needs to eat about 20% of his own weight.


The platypus can be preyed upon by many predators including foxes, snakes, and crocodiles. In Australia there is a very small population of platypus due to the large number of crocodiles that inhabit that area.


The platypus begins mating between the winter months. From June to October, with certain local variations between different populations in its range. The female is believed to be more likely to become sexually mature in her second year of life. It has also been confirmed that in females of more than new years of age they can still reproduce.

It normally lives in a burrow about 30 cm above the water level, but after mating the female burrows more deeply and elaborately over 20 m long and blocks it at intervals with plugs, which acts as a protection against to rising waters or to predators. They also regulate temperature and humidity. At the bottom of the burrow the female makes a padded surface with wet, folded and damp leaves. This material is introduced into the burrow, dragging it to the nest, tucking it under its curly tail. The male does not participate in the rearing of the young and retires to his burrow.

The female platypus has one pair of ovaries, but only the left one is functional. The laying is one to three eggs, usually two. They are small and leathery (very similar to those of reptiles) with a size of 11 mm. Before laying, the eggs develop in the uterus for about 28 days and only 10 days of external incubation are enough. After laying, the female curls around them to hatch them. The incubation period is divided into three phases. In the first phase, the embryo has no functional organs and depends on the yolk sac for its sustenance. The yolk is absorbed by the developing brood. During the second phase, the digits develop, and in the last phase, the egg tooth appears.

The young at birth are blind and hairless, making them extremely vulnerable. They feed on breast milk, but although the female has mammary glands, they do not have nipples and the milk is expelled through the pores of their skin and accumulates in the grooves of their abdomen. The mother only leaves the burrow for short periods to feed, but first creates a series of fine plugs of soil throughout the burrow to protect the young from predators. By pushing them outwards, a of their skin comes back and allows the burrow to remain dry.

After about five weeks, the female begins to be further away from her young and when they are four months old, the young leave the burrow.

State of conservation

The platypus is a threatened species as it is very sensitive to dirt in the water. Increased water pollution does not help it at all and its population decreases.

Popular culture

In an account by David Collins of the new colony between 1788 and 1801, he describes the platypus as "an amphibian animal much like a mole" and includes the animal's drawing.

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