Page 98 - Ultimate Visual Dictionary (DK)

PREHISTORIC EAR TH

Ornithopods 1 Orbit Cranium SKELETON OF
IGUANODON
Naris
ORNITHOPODS (“BIRD FEET”) were a group of
ornithischian (“bird-hipped”) dinosaurs. These Mandible Cervical
vertebra
bipedal and quadrupedal herbivores had a Cervical rib
horny beak, plant-cutting or grinding cheek
teeth, and a pelvic and tail region stiffened by Scapula Dorsal
vertebra
bony tendons. They evolved teeth and jaws Humerus
adapted to pulping vegetation and flourished
IGUANODON from the Middle Jurassic to the Late Sternal bone
TOOTH Sacral
Cretaceous period (165–65 million years ago) Radius
vertebra
in North America, Europe, Africa, China, Australia, and
Ulna
Antarctica. Some ornithopods were no larger than a dog, Caudal
Prepubic
while others were immense creatures up to 49 ft (15 m) long. process vertebra
Iguanodonts, an ornithopod group, had a broad, toothless beak Femur Neural
at the end of a long snout, large jaws with long rows of ridged, spine
Pubis
closely packed teeth for grinding vegetation, a bulky body, and
a heavy tail. Iguanodon and some other iguanodonts had large Tibia
thumb-spikes that were strong enough to stab attackers. Another Ilium
group, the hadrosaurs, such as Gryposaurus and Hadrosaurus, Chevron
Fibula Ischium
lived in Late Cretaceous times (97–65 million years ago) and
Metatarsal
with their broad beaks are sometimes known as “duckbills.”
They were characterized by their deep skulls and closely packed
rows of teeth, while some, such as Corythosaurus and Thigh
Lambeosaurus, had tall, hollow, bony head crests.

Heavy, stiff tail
EXTERNAL FEATURES OF
MANTELLISAURUS

SKULL AND MANDIBLE OF
YOUNG MANTELLISAURUS
Cheek Orbit Cranium
Maxilla tooth

Premaxilla
Knee
Paroccipital
process
Hind limb
Jugal bone
Coronoid Ankle
process
Toe

Foot
Predentary Dentary Mandible
bone bone Hooflike nail

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