Platypus

Platypus[1]
Conservation status
Near Threatened  (IUCN 3.1)[2]
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Synapsida
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)

The duck-billed platypus (Ornithorhynchus anatinus) is a small mammal. It is one of only two monotremes that survive today. It lives in eastern Australia, including Tasmania.^[3] The plural of platypus is just 'platypus'.^[4]

The platypus lives in rivers and river banks. It is one of only two families of mammals which lay eggs. The other is the Echidna, which has four species. The platypus was first described in detail in the early 19th century, but it took a while before biologists in England believed what they were reading.^[5]

These mammals are called monotremes because they have a common rear opening, the cloaca. Through this opening faeces and urine are voided (put out), and sexual activity takes place.^[6] This is a primitive (basal) feature of tetrapods, which monotremes, birds and reptiles have today. The later (derived) mammals have the system where the rear has two openings.

1. ↑ 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.
2. ↑ 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.
3. ↑ Cite error: The named reference dpiw was used but no text was provided for refs named (see the help page).
4. ↑ See David Attenborough's account of the discovery on the BBC. [1]
5. ↑ Moyal, Ann Mozley (2004). Platypus: the extraordinary story of how a curious creature baffled the world. Baltimore: The Johns Hopkins University Press. ISBN 0-8018-8052-1.
6. ↑ "Wildlife Finder - Platypus". BBC. Archived from the original on 2009-10-03. Retrieved 2009-10-03.