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Forty million years ago a diverse community of insects living at the
bottom of a tree in a temperate forest chanced into a sticky pool of
pine resin. Then a mere 67 years ago a young boy named David
Attenborough was given the amber stone containing the entombed bugs.
"Jewel of the Earth" explores the remarkable time capsule of ancient
life preserved in this and countless other samples of fossilized
tree resin, or amber.
Sir David Attenborough, now grown up and a celebrated naturalist and
TV personality, hosts the program. As he makes abundantly clear in
the show, he is still entranced with the amber specimen from his
youth and the seemingly magical quality of the material to serve as
a crystal-clear window to an age before humans walked the Earth.
(For another view on why amber insects are so fascinating, see
Bitten By the Bug.)
Coincidentally, David's brother Richard starred in the movie that
made amber famous: Jurassic Park, in which Richard plays a
billionaire entrepreneur who extracts DNA from amber-entombed
mosquitoes in order to clone living replicas of their
prey—dinosaurs. While such a scenario is probably unlikely,
amber can resurrect prehistoric life in a quite different way, as
NOVA demonstrates by probing the amber-encased clues that paint a
fascinating picture of ancient biomes.
For example, most of
the world's amber comes
from the Baltic region of northern Europe, where, on the ample
evidence of insects, plant fragments, and other trapped material, a
vast temperate forest flourished about 40 million years ago.
Attenborough's boyhood keepsake is a piece of Baltic amber, which he
investigates through a microscope with the help of biologist
Elzbieta Sontag of the University of Gdansk, finding a long-legged
fly, a fungus gnat, an aphid, an ant, and a mite—all denizens
of the lower forest floor.
By contrast, much of the amber found in the Dominican
Republic—the second most significant source studied so
far—is about 20 million years old and hails from an ancient
rain forest. George and Roberta Poinar of Oregon State University
have reconstructed this vanished ecosystem in spectacular detail,
based on such clues as a tadpole that probably resided in a
water-filled tropical bromeliad before being upended, along with a
marsh beetle, into a patch of tree resin that eventually turned into
amber. (For more clues to the primordial Dominican forest, see
Stories in the Amber.)
An even more ancient Dominican sample, from 150 million years ago,
contains a honeypot ant. Since this ant is now found only in
Australia, the specimen is evidence for a conjectured
super-continent that once comprised most of Earth's landmasses.
High-tech medical scanners have shed light on many other amber
inclusions, diagnosing a broken back on a gecko, for instance, which
suggests the lizard was a bird's prey before being accidentally
dropped into resin.
The most controversial research on amber, however, is the effort to
extract DNA from trapped creatures, just like in
Jurassic Park. So far, two teams, including the Poinars, have
announced success. However, follow-up studies indicate the DNA found
by both groups was a contaminant, not the real, ancient stuff.
Setbacks aside, scientists have only just begun to reveal the
secrets to be discovered in the warm, glowing, glassy world of
amber.
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Host David Attenborough holds up the piece of Baltic
amber he was given as a child—a piece that
contains, like many hunks of such fossil-bearing resin,
a microcosm of life that vanished millions of years ago.
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