Page 14 - Dinosaur (DK Eyewitness Books)

Jurassic times
Laurasia
Laurasia Laurasia
Atlantic
Ocean Tethys TȩȦ ȫȶȳȢȴȴȪȤ ȱȦȳȪȰȥ lasted from around 200 to 145 million years ago.
Sea
Gondwana It formed the middle part of the Mesozoic Era and is sometimes called the
Age of Giants because huge sauropod dinosaurs flourished at this time.
By now the supercontinent Pangaea had begun to crack. Where a great rift
split apart Earth’s continental crust, the Atlantic Ocean formed and then
widened, separating lands on either side. Moist winds from the seas could

THE JURASSIC WORLD reach many inland regions, bringing rain to places that had once
Pangaea broke up into a northern been deserts. It was warm everywhere. Plants began to grow
landmass called Laurasia and
a southern landmass called in barren lands, providing food for new kinds of large and
Gondwana. But these smaller small plant-eating dinosaurs. Above these, pterosaurs
supercontinents soon started
breaking up as well. Laurasia shared the air with the first birds, descendants of small
started to split into the northern
continents of North America, predatory dinosaurs. Early salamanders swam in lakes and streams, and
Europe, and Asia. Gondwana began Jurassic seas swarmed with big swimming reptiles. Many of these hunted
splitting into South America, Africa,
India, Australia, and Antarctica. fish that resembled some of those alive today.

Sprawling
limb
FIRST AMPHIBIANS
Frogs and salamanders as we know them
today first appeared in the Jurassic Period.
Karaurus is one of the earliest-known
salamanders. Paleontologists discovered
its remains in Late Jurassic rocks in
Kazakhstan. Despite its age, Karaurus’s
fossil skeleton resembles those of
salamanders that are alive today.
About 8 in (20 cm) long, this JURASSIC SEA REPTILES
small amphibian was a good Aside from its long, narrow jaws and vertical tail,
swimmer. It probably lived Ichthyosaurus (“fish lizard”) was shaped like a dolphin.
in streams or pools, snapping It grew 6½ ft (2 m) long and swam fast, using its large
up creatures such as snails eyes to spot the fish it hunted for food. Ichthyosaurs
and insects. were one of several groups of large Jurassic reptile
Backbone superbly adapted for life in the sea. They were not
related to dinosaurs.
Broad skull

GIANTS AND BIRDS
During the Jurassic Period, the prosauropods died out,
but sauropods and theropods flourished. Among them
were the largest plant-eating and meat-eating land
animals of the time, although some theropods from
this period were feathered creatures no bigger than
crows. The ornithopods, stegosaurs, and ankylosaurs
all appeared in the Jurassic Period.

SCELIDOSAURUS (190 MYA) BARAPASAURUS (190 MYA) GUANLONG (160 MYA)
The ankylosaur Scelidosaurus was one of Barapasaurus (“big-legged lizard”) gets its name from a Guanlong was one of the earliest members of the
the earliest and most primitive armored thigh bone 5½ ft (1.7 m) long. This sauropod had slim tyrannosauroid group of theropods. This crested
dinosaur. As long as a mid-sized car, it lived limbs and unusual hollows in its vertebrae (back bones). dinosaur from China grew only 10 ft (3 m) long,
in the northern landmass Laurasia. It grew 60 ft (18 m) long and lived in Jurassic India. but shared key features with Tyrannosaurus.

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