Which mammal lays eggs and has a duck-like bill?
Quick answer
The platypus is the egg-laying mammal with a duck-like bill. It lives in rivers and streams of eastern Australia and Tasmania. Along with the echidnas, it’s one of only five living monotremes, mammals that lay eggs. It also has webbed feet, a beaver-like tail and, in males, a venomous spur.
Key facts
- Scientific name
- Ornithorhynchus anatinus
- Group
- Monotreme (egg-laying mammal)
- Length
- About 40–60 cm including the tail
- Range
- Eastern Australia and Tasmania
“A hoax”
When the first platypus specimen reached Britain in 1798, scientists suspected it was a fake, with a duck’s bill sewn onto a mammal’s body. Zoologist George Shaw even checked for stitches.
Mammal or not?
| Mammal features | Unusual features |
|---|---|
| Fur | Lays eggs (usually two) |
| Produces milk | No nipples: milk seeps from skin patches |
| Warm-blooded | A bill, webbed feet and no teeth as adults |
The mother lays eggs in a burrow and curls around them for about 10 days until they hatch.
A sixth sense
The platypus hunts underwater with its eyes, ears and nostrils closed. Its rubbery bill holds tens of thousands of sensors that detect the tiny electric fields made by the muscles of shrimp, worms and insect larvae. This is called electroreception.
Venomous spur
Males have a sharp spur on each hind ankle connected to a venom gland. Venom production rises in the breeding season, suggesting it’s used against rival males. A sting isn’t deadly to humans but can cause severe pain lasting days. The platypus is one of very few venomous mammals; another is covered in is there a venomous primate.
More strange facts
- It has no stomach: its gullet connects straight to its intestines.
- Its fur glows blue-green under ultraviolet light.
- It stores fat in its tail.
The other monotremes
The four species of echidna are spiny, ant-eating monotremes found in Australia and New Guinea. Like the platypus, they lay eggs, but the female carries hers in a pouch.
For another Australian animal with a surprising feature, see which animal has fingerprints like humans.
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