The only two kinds known in the world live in Australia, the echidna (spiny anteater) and the duckbilled
For example, although the duckbilled
platypus is a mammal, it lays eggs, a trait predating mammals.
dinosaurs left their sound-producing trumpet crests behind as fossils.
The New Mexico hadrosaur, a kind of duckbilled
dinosaur, died about 70 million years ago.
If a human being's weight increased at the same rate as a duckbilled
dinosaur's from birth to adulthood, he'd end up as heavy as four double-decker buses
Mounted on a wall of the upstairs gallery is a duckbilled
Puzzle over the unicorn spike on the school-bus sized duckbilled
dinosaur Tsintaosaurus (TZINT-ow-SORE-us), the two-foot long spines of the bizarre Amargasaurus, and the world's longest claw - nearly two feet long - from a still-unknown Mongolian giant meat-eater.
Until now, this gap has caused some paleontologists to question whether the non-avian dinosaurs of the era - which included Tyrannosaurus rex, Triceratops, Torosaurus and the duckbilled
dinosaurs - gradually went extinct sometime before the meteor struck.
And no one with an IQ bigger than that of a duckbilled
platypus will believe a word of it.