Page 64 - Dinosaur (DK Eyewitness Books)

Rebuilding a dinosaur

DȪȨȨȪȯȨ ȶȱ Ȣ ȥȪȯȰȴȢȶȳpȴ bones is just the first step toward
learning what it looked like and putting it on show. Inside a museum
laboratory, technicians called preparators start by sawing off the
plaster jackets protecting the bones. If the bones are embedded
in rock, the next step is to extract them carefully.
Preparators chip away hard rock with chisels. They
use powered tools like dentists’ drills for detailed
work, and even acid for removing certain kinds of stone from
around the fossils. Once the bones are cleaned, paleontologists
can reconstruct the dinosaur’s skeleton by fitting them together.
Modelmakers can then be guided by paleontologists in building
EXPOSING THE FOSSIL a lifelike restoration of the animal, using bumps and ridges on the
A technician uses dilute acetic acid to expose
embryos hidden in fossil dinosaur eggs. Each bones as clues to where muscles and other tissues were attached.
day, acid eats away a wafer-thin layer of the
stony material around the embryos without
harming their frail bones, which have a
different chemical composition. Washing
and drying the embryos is part of this
Ligament scar
process, which can last up to a year.

Cartilage cap
of ankle joint
FINDING CLUES
Fossil bones can tell us about muscles
and other tissues that have vanished.
The upper end of this third
metatarsal (foot) bone of an
Iguanodon is roughened and
shows where cartilage (gristle)
protected the ankle joint. The
bottom end is where cartilage
protected this bone against
the first phalanx (toe
bone). A scar marks
where a ligament
joined this bone to the
fourth metatarsal bone. Cartilage
surface of joint
for first phalanx

FLESH AND BONES
This model shows a
freshly dead Baryonyx
lying on the bottom of a
lake. A sculptor made this
ON DISPLAY realistic model by studying the
A cast of a Diplodocus skeleton forms the centerpiece in the way the dinosaur’s bones were
main hall of London’s Natural History Museum. Museums arranged when paleontologists dug them
worldwide display replicas of dinosaur skeletons. The up. Scientists and the modelmaker then worked out
replicas are cast from molds made from real fossils, many where to add muscles, skin, and other tissues that
of them unique and too fragile to be put on display. would bulk out the body.

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