The echidna , a distant cousin of the anteater, also lays eggs and is found in Australia and New Guinea. Both the platypus and the echnida are monotremes, meaning that they lay eggs and have a single opening cloaca for reproduction and elimination of wastes. Home Ocean Facts What is a platypus? What is a platypus?
The Platypus propels itself through the water by using its front, short, webbed limbs, and the partially-webbed hind feet act as rudders. Behind its distinctive bill are the grooves that house the ear openings and the eyes which close when the animal dives.
The Platypus uses its tail for storage of fat reserves and the strong claws on its feet for burrowing and moving on land. In addition, males possess a horny spur on their ankles, which is connected to a venom gland in the upper leg, making the Platypus one of the few venomous mammals. Get our monthly emails for amazing animals, research insights and museum events.
The skeleton of the Platypus is heavy and has several similarities to that of fossil and modern reptiles. These include pectoral girdles made of five bones, splayed legs and rudimentary ribs on the neck vertebrae.
Platypuses occur in freshwater systems from tropical rainforest lowlands and plateaus of far northern Queensland to cold, high altitudes of Tasmania and the Australian Alps.
They feed in both slow-moving and rapid riffle parts of streams, but show preference to coarser bottom substrates, particularly cobbles and gravel.
When not foraging, the Platypus spends most of the time in its burrow in the bank of the river, creek or a pond. At times, the individuals use rocky crevices and stream debris as shelters, or they burrow under the roots of vegetation near the stream.
Hence, the ideal habitat for the species includes a river or a stream with earth banks and native vegetation that provides shading of the stream and cover near the bank.
The presence of logs, twigs, and roots, as well as cobbled or gravel water substrate result in increased microinvertebrate fauna a main food source , and the Platypus also tends to be more abundant in areas with pool-riffle sequences. Platypus is endemic to Australia and is dependent on rivers, streams and bodies of freshwater. It is present in eastern Queensland and New South Wales, eastern, central and southwestern Victoria and throughout Tasmania. The western limits of the range are poorly known.
Nowadays it is extinct from that state, except for the introduced population on the western end of Kangaroo Island. There is no evidence that the animal occurred naturally in Western Australia, despite several unsuccessful attempts to introduce it there. Within its current distribution, the occurrence of the Platypus is reasonably continuous in some, but discontinuous in other catchments. Platypuses are active all year round, but mostly during twilight and in the night.
During day, individuals shelter in a short burrow in bank. The activity patterns of these animals are determined by a number of factors including: locality, human activity, ambient temperatures, day length and food availability. The Platypus feeds mainly during the night on a wide variety of aquatic invertebrates.
The average foraging periods last for hours per day, and the distances the animals move during this time vary between individuals and their distribution. The animal closes its eyes, ears and nostrils when foraging underwater and its primary sense organ is the bill, equipped with receptors sensitive to pressure, and with electro-receptors. The precise way in which the Platypus uses the bill to detect prey is still unknown, but the bill serves to find and sift small prey from the substrate, while larger prey is taken individually.
The Platypus stays underwater for between seconds, collecting the invertebrates from the river bottom and storing them in its cheek-pouches. It then chews the food using its horny, grinding plates, while it floats and rests on the water surface.
Diet of the Platypus consists mainly of the benthic invertebrates, particularly the insect larvae. The species also feeds on free-swimming organisms: shrimps, swimming beetles, water bugs and tadpoles, and at times worms, freshwater pea mussels and snails. Occasionally the animals catch cicadas and moths from the water surface. Many animals lay eggs to reproduce. Platypuses are one of the few mammals to lay eggs, the others being spiny anteaters of Australia and New Guinea. A female platypus lays one to three eggs, usually two, that she curls around in a burrow for about 10 days before they hatch.
The mother has mammary glands that produce milk with which she nurses the babies for more than three months. The platypus is also distinctive in its role as a venomous mammal. The southeastern short-tailed shrew is another. Its salivary glands produce venom that enters the body of small animals when the shrew bites them. The venom glands of platypuses are located on the hind feet, which have a sharp, protruding, grooved spur. The venomous spines are only present in males and are not known to be used in capturing prey.
It took more than 80 years just to work out how this animal fits into the tree of life. Since then, biologists have gone even further and found that it possesses a range of features that mean it is among the most unusual creatures on Earth.
As a mammal that shares many characteristics with birds and reptiles, the platypus holds the key to unlocking some fundamental evolutionary mysteries. Now, geneticists have mapped its entire genome and are starting to understand how it came to be so strange — and what it can tell us about the origins of all mammals, including us.
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