Page 86 - Ultimate Visual Dictionary (DK)

PREHISTORIC EAR TH
Theropods 1 Ilio-tibial muscle

Ilio-femoral muscle
AN ENORMOUSLY SUCCESSFUL SUBGROUP of the Saurischia, INTERNAL ANATOMY OF
the bipedal (two-footed) theropods (“beast feet”) emerged ALBERTOSAURUS LEG
230 million years ago in Late Triassic times; the oldest known
example comes from South America. Theropods spanned the
Femoro-tibial
age of most dinosaurs (230–65 million years ago) and beyond,
muscle
and included most of the known predatory dinosaurs. The
Internal tibial
typical theropod had smallish arms with sharp, clawed fingers; flexor muscle
powerful jaws lined with sharp teeth; an S-shaped neck; long,
muscular hind limbs; and clawed, usually four-toed feet. Many Femur
theropods may have been warm-blooded; most were exclusively Ilio-fibular
muscle
carnivorous. Theropods ranged from animals no larger than
a chicken to huge creatures, such as Tyrannosaurus and
Gastrocnemius
Baryonyx. The group also included ostrichlike omnivores muscle Ambiens
and herbivores with toothless beaks, such as Struthiomimus Digital flexor muscle
and Gallimimus. Birds are dinosaurs and evolved from muscle Femoro-
tibial
within a group of tetanuran theropods called maniraptorans.
Fibula muscle
Archaeopteryx, small and feathered, was the first known
Anterior
bird and lived alongside other dinosaurs. Tarsal tibial
muscle
Cranium Supraoccipital crest Metatarsal Common digital
extensor muscle
Orbit
Naris Cervical vertebrae
Toe
Dorsal vertebrae
Claw
Ilium
Cervical
rib
Scapula
Mandible Shoulder joint
Serrated Ulna
tooth
Phalanges
Naris Eye Femur Ischium
Metacarpals
Wrist joint Hip
joint
Elbow joint Coracoid Rib
Thigh
Humerus
Scaly skin
Tail Pubis Knee
joint
Forelimb
Tibia
Fibula
Hand
Knee Hind limb SKELETON OF
Ankle TYRANNOSAURUS
Ankle Metatarsals
joint
Toe Foot Phalanges
Claw
Hallux
(first toe)
EXTERNAL FEATURES OF TYRANNOSAURUS
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