Page 21 - Dinosaur (DK Eyewitness Books)

Fossilized skin impression
covers fossil bones

DINOSAUR MUMMY
PREHISTORIC TREASURE This Edmontosaurus fossil has
Almost all bones in this Dilophosaurus skeleton are still traces of the animal’s pebbly
intact and most are connected to each other, much as Body is twisted skin. River mud covered
they had been while the dinosaur was alive. Nothing had because tendons have the dead dinosaur before its
disturbed this creature’s corpse before a rocky tomb covered shrunk due to dry heat body had decayed. A mold
and protected it. Fossil dinosaur skeletons as complete as (impression) of the animal’s skin
this are extremely rare. Dinosaur hunters are more likely was filled by mud that later turned
to find tiny isolated scraps of bone, because after most Mummified to rock. This preserved the shape
dinosaurs died, scavenging animals and the weather would Edmontosaurus of the skin. Such a find is called a
break up the bodies, damaging and scattering the bones. mummy and helps us to learn more
about the soft tissues of dinosaurs.

Impression of
MOLDS AND CASTS
the organism
Sometimes a dead organism buried in mud
or sand rots away completely, leaving its
impression behind. This kind of fossil is
a mold. As the mud or sand turns
into rock, minerals may seep into the Ammonite
impression and replace it with a stony mold
lump in the shape of the organism. Such
a fossil is called a cast. Many animal and
plant fossils consist of molds or casts.

Ammonite
cast

Stony lump
in the shape of
the organism

Paleontologist TRACE FOSSILS
excavating a A footprint shows where a dinosaur once walked through mud
dinosaur fossil that later hardened into rock. Fossil eggs, nests, and dung also
reveal how the living dinosaurs behaved. Such fossilized signs, or
Eroded traces, of an animal (rather than fossils of the animal itself) are
desert known as trace fossils. They help us to learn about how dinosaurs
landscape moved, how they bred, and what they ate—information that we
could not easily guess at from the reptiles’ fossil bones alone.

Frond-shaped
carbon film

CARBONIZED PLANT TISSUE
A shiny black and brown film
made of carbon is all that remains
of this fern frond preserved in a rock.
Carbonized and other kinds of plant
fossils help scientists to build a picture
of what the vegetation was like in a
particular place at a particular time.