Page 90 - The Dinosaur Book and Other Wonders of the Prehistoric World (DK-Smithsonian)

Hadrosaurs The unique head

crest changed
shape with age.
Lambeosaurus
Saurolophus

The crest tilted
backward.

The backward-
pointing crest was up
to 3 ft (1 m) long, and
was supported by a
hollow bone.

Some Edmontosaurus
were flat-headed.

Edmontosaurus

The snout was
long and broad.

Hadrosaurus was
about 30 ft (9 m) long.

Fossil evidence shows
that Edmontosaurus
had scaly skin with
large bumps.

Hadrosaurus Shantungosaurus

Hadrosaurs lived during the Cretaceous crop leaves. Similar to earlier iguanodontians,
Period, between 100–66 million years but with more complex teeth and jaws,
ago. They roamed the forests and swamps of hadrosaurs had jaws lined with hundreds of
North and South America, Europe, and Asia. teeth arranged like the teeth of a file. Grinding
They were large plant-eaters, and many of them together, these teeth reduced tough plant food
88 had a broad, ducklike beak that they used to to a juicy, easily digested pulp, ensuring that a

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