Page 161 - The Dinosaur Book and Other Wonders of the Prehistoric World (DK-Smithsonian)

The streamlined body of
A seabed dweller, this squidlike mollusk probably
this crinoid used its made it a fast swimmer.
petal-like arms to filter
food from seawater. Although very similar to
modern horseshoe crabs,
this one lived at the same time
as the giant dinosaurs.

The long stem
at the base of its
body was attached Life in Mesozoic seas
to a hard surface.

Crinoid fossil Belemnite Horseshoe crab fossil

After
150 million
years, shiny
Like a squid, the scales are still
belemnite caught
prey with two long, visible on this
suckered tentacles.
amazing
fossil. Fossils of the 6-ft- (1.8-m-) long
Brittlestars are slender, Lepidotes have been found
flexible starfish that have throughout the world.
Lepidotes
been foraging for food on the
seabed for 500 million years.
fossil

The blunt,
teardrop-shaped
teeth were used to
Brittlestar fossil break open shellfish.

many new forms. These included fish, sharks, belemnites, both of which were relatives
and marine reptiles, as well as invertebrates of squid. They perished in the mass extinction
such as shelled mollusks, crabs, and starfish. that ended the Mesozoic Era and destroyed
Hard-shelled invertebrates in particular were the giant dinosaurs. But other types of sea
common and have been fossilized in large creature survived and still flourish in the
numbers. They included ammonites and world’s oceans. 159

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