Name: Platypus (Ornithorhynchus anatinus)
Size: Approximately 30-40cm long, weigh up to 3kg.
Diet: Carnivore – aquatic invertebrates.
Habitat: Freshwater creeks, rivers and streams across eastern and southern Australia.
Superpower: Male platypuses are venomous – one of a few venomous mammals in existence.
No argument: the platypus is one of the most extraordinary animals on the planet.
Famous for their quirky, unusual appearance, they were originally thought to be a hoax combination of different animals when specimens were first seen by English naturalists. Cryptic and elusive, they are often called shy, but that’s mostly because they are well camouflaged within their environment and spend most of their lives underwater or in their burrows.
Breeding season starts around September each year, but before this, the males need to find a territory with resident females. While the platypus may look very cute, they also have a dark side: males have sharp spurs on their hind feet that are connected to a venom gland in their leg. They use these spurs as weapons to fight other males as they contest breeding rights.
Males and females conduct a beguiling courtship ritual prior to mating as they assess each other’s suitability. First the male will grab the tail of the female in his bill, while she swims around in a series of loops and twists through the water. If things are going swimmingly, the female will then twist around and clasp her bill on the male’s tail, so they complete a romantic loop tracing circles underwater.
After mating, the female constructs a nest by carrying leaves and grasses in her tail, which she takes underground into a special nesting burrow where she will lay her eggs – and here’s where our Mammal of the Year title really should be a no-contest. A mammal that lays eggs? This is the preposterous platypus, remember – a monotreme, sharing this astonishing ability only with the various echidna species. She will normally lay one or two soft-shelled eggs, similar to reptile eggs, and incubate them for about 10 days. When the puggles (not kidding) hatch, they are the size of a jellybean and fur-less. They live underground for the next four months, suckling from their mum – but the milk is secreted a bit differently to other mammals. Platypus don’t have teats, so milk drips out of patches on mum’s belly, which the puggles lap up.
At four months of age, the young are almost fully grown, about 80% the size of their parent. This is when they are weaned from milk and leave the nesting burrow for the first time. No swimming lessons from parents are required – foraging and underwater acrobatics all comes naturally.
The platypus is a carnivorous generalist feeder in the water, eating a variety of aquatic invertebrates such as caddisfly and dragonfly nymphs, shrimp, mussels, worms, midge larvae and crayfish. They locate their prey by using specialised receptors on their bills. Electroreceptors can detect both AC and DC current, while the mechano-receptors detect vibrations, water pressure and movement. The information from these receptors allows the platypus to navigate under the water and also to locate and capture their prey.
Yes, it’s a strange, wonderful conundrum among our pantheon of marvellous mammals, but the platypus is terribly special – and even deserves your vote as the Mammal of the Millennium.
Originally published by Cosmos as Platypus: the preposterous platypus is no joke
Dr Jessica Thomas is a platypus Specialist based at Healesville Sanctuary. She completed her PhD on breeding biology of the platypus and has worked for Zoos Victoria for 15 years.
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