Australia's 'irreplaceable' platypus threatened by dams: study
The future of the platypus, a unique duck-billed, egg-laying mammal only found in Australia, is under threat because they cannot climb over tall river dams, according to a new study.. As well as its duck-like bill and egg-laying, it is a rare venomous mammal, brandishing centimetre-long poisonous spurs on its hind legs.