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02-06-06
By David Stauth, 541-737-0787
Source: George Poinar, Jr., 541-752-0917
CORVALLIS, Ore. - Scientists at Oregon State University have produced one of the most detailed and accurate ecological descriptions ever made of a prehistoric rain forest, based on the study of insects, plants, seeds and other material - almost all of which is now extinct - found trapped in amber about 20 million years ago.
This and other work relating to one of nature's most fascinating rocks will be explored on Tuesday, Feb. 14, on a Public Broadcasting System national television special, titled "Jewel of the Earth." The Nova special (check local listings for exact time) will be narrated by Sir David Attenborough.
"Recreating a forest with what you can tell from insects, plants, a little feather or a hair, is like being a detective or trying to assemble a jigsaw puzzle," Poinar said. "It's quite fascinating, and of course there are always a few pieces missing. But amber is the best tool we have to really bring these primitive forests to life."
As a semi-precious stone that first begins to form as sap oozing from a tree, amber has the unique ability to trap very small animals or other materials and - as a natural embalming agent - display them in nearly perfect, three-dimensional form millions of years later. This phenomenon has been invaluable in scientific and ecological research, and among other things, formed the scientific premise in the movie Jurassic Park, for the "dinosaur DNA" found in mosquitoes.
Poinar, an entomologist and one of the world's leading experts on the life forms found trapped in amber, has published and written extensively on the mysteries that amber is still helping to solve. Even if the process of discovery is not always the tidy laboratories some researchers are used to.
"We traveled more than 1,500 miles through the forests and jungles of the Dominican Republic in the 1980s to get the samples we needed," Poinar said.
"Sometimes their idea of a mine was a hole you crawled into on your knees, half full of water, hundreds of feet into a hill, carrying a candle so you could tell when you were about to asphyxiate from lack of oxygen. Around then, there were also a lot of public strikes, rebels trying to take control of the country, other things. It was interesting."
At various times in his quest for amber, Poinar has been chased through the streets of Morocco by a knife-wielding man, threatened by armed residents protecting their local amber mines, or had to travel with soldiers to pick his way through explosive mine fields in Lebanon.
But for the patient and persistent, amber reveals many secrets.
"In our rain forest work, we were able to look at different samples and find the petal, stamen, even pollen grains from a single tree species," Poinar said. "Bit by bit, we can re-create the whole forest that way, the palm and mahogany trees, a tadpole and marsh beetle, the many insects and other animal life, the carnivores that would have fed on them."
Among other things, Poinar said, amber reveals a world that is in constant flux - where continuing evolution and routine species extinction is the rule, not the exception.
"We still find some descendants of prehistoric trees or insects, but very few are still completely the same, most are extinct," Poinar said. "And you can see how species may have survived in one little corner of the world and gone extinct everywhere else. There's a honeypot ant that, from amber research, we can tell was once common in the Caribbean and Mexico. But now it's found only as a related species in one small part of Australia. All of those species probably date back to a common ancestor when Earth's tectonic plates were together in one large super continent. Some populations survived, others didn't."
Amber can even reveal secrets about medical history, Poinar says. One recent publication announced the discovery in amber of the parasite that causes malaria, found inside the intestine of a mosquito in the Dominican Republic - the oldest known record of that disease which apparently pre-dates modern humans, and may have evolved separately in the New World as well as Africa.
Unlike conventional fossils, amber specimens provide a visually stunning representation of an animal or plant almost exactly like the way it looked the day it was trapped and died. Poinar believes his research group has also obtained some DNA fragments from amber specimens, although other groups have argued the findings were DNA contaminants from elsewhere.
In order to make sense out of all his specimens and findings, Poinar has tapped into the expertise of other scientists all over the world. He once found a feather expert at the Smithsonian Institution who was able to help explain the significance of certain feather characteristics - and, in other work, had aided police detectives trying to identify feathers at a crime scene where bullets had been fired through a feather pillow.
"It's a huge challenge to re-create a forest that's millions of years old, so we need all the help we can find," Poinar said. "But it's always amazing what hidden secrets amber can reveal to us."
About the OSU College of Science: As one of the largest academic units at OSU, the College of Science has 14 departments and programs, 13 pre-professional programs, and provides the basic science courses essential to the education of every OSU student. Its faculty are international leaders in scientific research.