Page 54 - The Dinosaur Book and Other Wonders of the Prehistoric World (DK-Smithsonian)
P. 54
Rise of
the reptiles Mesosaurus
Before the dinosaurs Proterogyrinus This aquatic animal lived
like an amphibian but had
developed reptilelike eggs.
Tough, bony plates helped
Scutosaurus from predators. The broad,
protect this plant-eater
strong skull was
probably adapted
for burrowing.
Westlothiana
is named after
West Lothian
in Scotland, where Procolophon
its fossils were
Stout, pillarlike legs found. The slender body and
supported the animal short legs may have been
high off the ground. an adaptation for
burrowing.
Scales stopped vital
body moisture escaping
easily through the skin.
Early amphibians could live on land, but Westlothiana evolved eggs enclosed in shells
they lost body moisture through their thin that retained moisture, so they could be laid
skin and had to lay their eggs in water or in dry places. They also developed thicker
damp places if they were to survive. During skin covered with tough, waterproof scales that
the Carboniferous Period, some amphibianlike stopped the body losing moisture. They were the
52 animals resembling Proterogyrinus and ancestors of the first true reptiles—animals such
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