Jewel of the Earth: Amber Reveals the Secrets of Ancient Worlds (NOVA DVD)
Summary: 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.
Angie's Comments: This NOVA program is an interesting look into how scientists can use the plants and animals trapped in amber to learn more about the world millions of years ago. The amount of information that can be found just from one insect is amazing!
Recommended for people interested
in geology and the ancient past.
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July 30, 2015
Jewel of the Earth
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