Page 42 - The Dinosaur Book and Other Wonders of the Prehistoric World (DK-Smithsonian)

Fish armor protected by bony scales.
The back of this
early jawless fish was

Before the dinosaurs The broad head was covered Drepanaspis Drepanaspis had Birkenia
in small bony plates, forming a
strong suit of armor.

a fin only on its tail.

The mouth
pointed upward.

Most of the body was
not armored, allowing
flexibility for swimming.

Dunkleosteus
Rolfosteus was only
could grow to a about 12 in (30 cm) long.
colossal 20 ft
(6 m) long—as big
The head shield extended
as a great white into a long tubelike snout that Rolfosteus
shark. may have been used to uncover
prey hiding in the seabed.

Cephalaspis

The mouth was underneath
its broad head shield,
suggesting that Cephalaspis
fed on the seabed.

Many early fish had tough armor much smaller than the armored, jawed fish that
protecting their heads, and sometimes evolved later—the placoderms. Some of these
their bodies too. The first of these armored massive jawed fish were monstrous looking.
fish appeared more than 400 million years ago. Their heads and upper bodies were covered
The jawless Cephalaspis and Drepanaspis had with tough, overlapping plates of bone that
40 big horseshoe-shaped head shields. They were were hinged to allow movement. The armor

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