Scientific Name: Ornithorhynchus anatinus
Common Name: Platypus
Ornithorhynchus anatinus. © Adam Gadawski
The platypus is an egg laying, carnivorous mammal. It is a medium sized animal that weighs between 1 kg and 2 kg on average and ranges between 40 cm and 55 cm in length. It has a duck-like bill, short brown fur, webbed feet and a fairly wide, flat tail. The platypus is a monotreme and like most other monotremes, has a body temperature of 32 degrees Celsius. It is also nocturnal or more specifically, crepuscular (active at dawn and dusk). The males have a venomous spike on each hind leg which is used for defensive purposes. The platypus swims with its eyes, ears and nostrils closed so it uses electrolocation to sense moving objects around it.
The platypus can only be found in Australia. It is most commonly found in all sorts of fresh water streams including alpine creeks and lowland rivers but can also inhabit lakes, farm dams and reservoirs. It generally lives near a steep, vegetated bank in which it can burrow. The burrows are generally shallow, but females can create burrows up to 20 metres deep for breeding purposes.
Specific Adaptations to the Environment
Over time, the platypus has made two very important adaptations that allow it to hunt effectively. First, its electrolocation ability makes up for the fact that it can’t see, hear or smell anything in the water when it swims. This ability allows the platypus to detect the small electric impulses given off by animals when they move. Second, it uses its bill to stir up the bottom of the stream, forcing its prey to move.
Platypuses reproduce in early spring/late winter. The female can lay 1-3 eggs but usually ends up laying 2. The female curls around the eggs to incubate them until they hatch while the male leaves and has nothing to do with caring for the offspring. When they finally do hatch, the babies stay in the burrow for 3 to 4 months and feed on milk from their mothers. Unlike most other mammals, the milk is secreted from the skin of the mother since platypuses do not have nipples. During the 3 to 4 months, the mother leaves only for short increments of time, and when she does, she blocks off the burrow. The offspring leave after this period.
Ornithorhynchus anatinus swimming out of its burrow. Image © Australian Wildlife.
- Kingdom: Animalia
- Phylum: Chordata
- Class: Mammalia
- Order: Monotremata
- Family: Ornithorhynchidae
- Genus: Ornithorhynchus
- Species: Ornithorhynchus anatinus
Importance of the Organism to the Ecosystem:
Since the platypus is a carnivore, it plays the typical role of the carnivore in an ecosystem. It keeps the populations of species in lower levels of the food chain in check.
Common or Endangered?
The platypus is a fairly common animal in Australia although it is listed as “near threatened” due to water pollution. Also, more recently, a fungal disease has started migrating from the mainland to Tasmanian populations. Platypuses in the mainland had developed an immunity to this disease but in Tasmania, it is killing about 35% of animals in affected populations.
Ornithorhynchus anatinus on a river bank. Image © Australian Wildlife.
The Adventures of Pluto the Platypus
- You have just escaped from the zoo and are free in Australia. To return to your homeland, your choices are to go to Eastern Queensland or South Australia.
- If you would like to go to Eastern Queensland go to 
- If you would like to go to South Australia go to 
Go to paragraph  to continue with the adventure that is your life.
If you would like to try your luck again, I suggest you brush up on your knowledge of Ornithorhynchus anatinus. Go back to paragraph  if you would like to try again.
- Beach front for me, the beautiful ocean, and all those colorful fish -Yum, Yum! 
- It’s the ranch for me, dry weather helps my lungs. 
- A nice little river, perhaps with a small pond is best suited for me. 
- If you would like to go up to your prey and inject it with venom –how could venom not work- go to .
- If you would like you could use electrolocation by locating your prey using electric fields generated from the motion of other organisms around you, go to .
- This is hopeless I am never going to catch anything, I quit. I will just sleep somewhere. 
- Continue hunting this way, never give up! 
- Go with electrolocation to find your prey. 
- I hunt underwater, therefore I live underwater, I will choose a burrow underneath the river. 
- I could just lie down on my back, and pretend that I don’t have predators. 
- Perhaps a burrow would be the best place for me, away from predators, but still giving me air to breath. 
- Please go to  to continue
- It was nothing, what could worry you, mighty Pluto the Platypus 
- You have an uncertain feeling, and rush to the water and dive in, better to be safe than sorry. 
CONGRATULATIONS! YOU SURVIVED THE ADVENTURES OF PLUTO THE PLATYPUS