A description of a 95-million-year-old amber depositthe first major discovery of its kind from the African continentis adding new fungus, insects, spiders, nematodes, and even bacteria to an ecosystem that had been shared by dinosaurs. In addition, the amber deposit may provide fresh insights into the rise and diversification of flowering plants during the Cretaceous. The new paper, published in the current issue of the Proceedings of the National Academy of Sciences, reconstructs an ancient tropical forest uncovered in present-day Ethiopia and is the work of an international team of 20 scientists.
"Until now, we had discovered virtually no Cretaceous amber sites from the southern hemisphere's Gondwanan supercontinent," says author Paul Nascimbene of the Division of Invertebrate Zoology at the American Museum of Natural History. "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," says first author Alexander Schmidt of the University of Gttingen in Germany. "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, along with Kenneth Anderson from 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 definitively from non-flowering plants, or gymnosperms.
"The tree that produced the sap is still unknown, but the amber's chemistry is s
|Contact: Kristin Elise Phillips|
American Museum of Natural History