Dear Friends,
Jurassic Park anyone?
http://www.world-science.net/othernews/100405_amber.htm
Be Well.
David
Jurassic Park anyone?
http://www.world-science.net/othernews/100405_amber.htm
Be Well.
David
Amber yields secrets from dinosaur era
April 5, 2010
Courtesy of the American
Museum of Natural History
and World Science staff
A 95-million-year-old amber deposit is adding newfound fungus, insects, spiders, nematode worms, and bacteria to the portrait of an ancient ecosystem also shared by dinosaurs, scientists say.
Amber is hardened, fossilized tree sap whose glassy, jewel-like and yellowish form often contains small creatures trapped from the time of its origin and preserved nearly perfectly.
The newfound deposit, dated to the Cretaceous era that was the last major period of the dinosaurs, is reported to be the first major discovery of its kind from Africa.
The finding may also provide insights into the rise and diversification of flowering plants during the Cretaceous, researchers say. A report by 20 scientists on the discovery, in the current issue of the research journal Proceedings of the National Academy of Sciences, reconstructs an ancient tropical forest uncovered in present-day Ethiopia.
"Until now, we had discovered virtually no Cretaceous amber sites from the southern hemisphere's Gondwanan supercontinent, a land mass that included modern Africa, said research group member Paul Nascimbene of the American Museum of Natural History in New York. "Significant Cretaceous amber deposits had been found primarily in North America and Eurasia."
"The first angiosperms, or flowering plants, appeared and diversified in the Cretaceous," added Alexander Schmidt of the University of Göttingen in Germany, another of the investigators. "Their rise to dominance drastically changed terrestrial ecosystems, and the Ethiopian amber deposit sheds light on this time of change."
While some of the authors worked on the geological setting and the fossils entombed within the amber, Nascimbene, with Kenneth Anderson of Southern Illinois University, studied the amber itself. They found that the resin that seeped from these Cretaceous Gondwanan trees is similar chemically to more recent ambers from flowering plants in Miocene deposits found in Mexico and the Dominican Republic. The amber's chemical designation is Class Ic, and it is the only Ic fossil resin discovered thus far from the Cretaceous. All other documented Cretaceous ambers are from non-flowering plants, or gymnosperms.
"The tree that produced the sap is still unknown, but the amber's chemistry is surprisingly very much like that of a group of more recent New World angiosperms [flowering plants] called Hymenaea," says Nascimbene. "This amber could be from an early angiosperm or a previously-unknown conifer that is quite distinct from the other known Cretaceous amber-producing gymnosperms."
Other team members discovered 30 insects and spiders trapped in the amber from thirteen families of organisms. These fossils represent some of the earliest African fossil records for a variety of types, including wasps, barklice, moths, beetles, a primitive ant, a rare insect called a zorapteran, and a sheet-web weaving spider. Parasitic fungi that lived on the trees were also found, as well as filaments of bacteria and the remains of flowering plants and ferns.
Amber is hardened, fossilized tree sap whose glassy, jewel-like and yellowish form often contains small creatures trapped from the time of its origin and preserved nearly perfectly.
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A chalcid wasp in Ethiopian amber, 0.6 millimeters long. (Courtesy U. of Vienna) |
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The finding may also provide insights into the rise and diversification of flowering plants during the Cretaceous, researchers say. A report by 20 scientists on the discovery, in the current issue of the research journal Proceedings of the National Academy of Sciences, reconstructs an ancient tropical forest uncovered in present-day Ethiopia.
"Until now, we had discovered virtually no Cretaceous amber sites from the southern hemisphere's Gondwanan supercontinent, a land mass that included modern Africa, said research group member Paul Nascimbene of the American Museum of Natural History in New York. "Significant Cretaceous amber deposits had been found primarily in North America and Eurasia."
"The first angiosperms, or flowering plants, appeared and diversified in the Cretaceous," added Alexander Schmidt of the University of Göttingen in Germany, another of the investigators. "Their rise to dominance drastically changed terrestrial ecosystems, and the Ethiopian amber deposit sheds light on this time of change."
While some of the authors worked on the geological setting and the fossils entombed within the amber, Nascimbene, with Kenneth Anderson of Southern Illinois University, studied the amber itself. They found that the resin that seeped from these Cretaceous Gondwanan trees is similar chemically to more recent ambers from flowering plants in Miocene deposits found in Mexico and the Dominican Republic. The amber's chemical designation is Class Ic, and it is the only Ic fossil resin discovered thus far from the Cretaceous. All other documented Cretaceous ambers are from non-flowering plants, or gymnosperms.
"The tree that produced the sap is still unknown, but the amber's chemistry is surprisingly very much like that of a group of more recent New World angiosperms [flowering plants] called Hymenaea," says Nascimbene. "This amber could be from an early angiosperm or a previously-unknown conifer that is quite distinct from the other known Cretaceous amber-producing gymnosperms."
Other team members discovered 30 insects and spiders trapped in the amber from thirteen families of organisms. These fossils represent some of the earliest African fossil records for a variety of types, including wasps, barklice, moths, beetles, a primitive ant, a rare insect called a zorapteran, and a sheet-web weaving spider. Parasitic fungi that lived on the trees were also found, as well as filaments of bacteria and the remains of flowering plants and ferns.
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