Page 90 - DINOSOUR ATLAS

excavation and display
replica skeletons .
creating barosaurus
Most dinosaur fossils are too fragile to be
reconstructed into whole skeletons, and some bones Reconstructing a skeleton
may be missing. Exhibits like this spectacular, rearing involves making exact replicas
Barosaurus in the American Museum of Natural History of all the fossil bones. The
are built up from replica bones made from the fossils. paleontologists also replace any
that are missing, basing them on
the fossils of related animals.

u dinosaur molds
Each fossil bone is covered with
a thick layer of liquid rubber.
When it has set, the rubber is
peeled away in two halves and
reinforced with cloth and plastic.

u computer modeling
Paleontologists can use computers
to reconstruct dinosaurs on screen, using data
from the fossils. They can also use medical scanning
techniques to see inside fossils, and reveal things like
the embryos inside fossilized dinosaur eggs.

u preparing for casting
The outside of each rubber mold
is stiffened with fiberglass. The
inside is then painted with the
liquid plastic that will form
the surface of the replica bone.

u making the cast
The molds are fitted together,
and liquefied foam plastic is
poured into the cavity. This
forms the strong but lightweight
core of each replica bone.

u virtual reality
Computer reconstruction enables u the replica bones
paleontologists to show how dinosaurs like When the plastic has solidified,
this Tyrannosaurus rex moved when they were the molds are carefully eased
alive, providing insights into how they may away. The replica bones are
have behaved. This work has been the basis cleaned, painted, and assembled
of several television programs depicting on a strong metal framework.
dinosaurs as living animals rather than fossils.
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