Word: resins
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Dates: during 1990-1999
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...substance that's essentially dried-up tree resin. The viscous stuff that eventually turns into amber comes from a variety of ancient trees, mostly conifers, including pines and extinct relatives of sequoias and cedars, but also some deciduous trees. It probably evolved, says Grimaldi, as a defense against wood-boring insects. "As it dripped down the bark," he explains, "it acted like flypaper and encapsulated them, hermetically sealing the trees' wounds at the same time...
Eventually the trees and their stalactites of dried resin fell, some of them ending up buried in soft sediments at the bottom of still and shallow bodies of water. There, over millions of years, the molecules of resin gradually amalgamated into long, durable chains, creating a material remarkably like plastic: airtight, watertight, chemically inert...
...right, the secret may be amber. This semiprecious substance, observes Ward Wheeler, a molecular evolutionist at the American Museum of Natural History in New York City, provides a unique window on the history of life. Down through the ages, sudden flows of sticky, honey-colored tree resin have ensnared all manner of small life forms, including beetles, spiders, and even lizards and frogs. Moreover, as this natural polymer hardens, it becomes virtually airtight and waterproof. Not only are extinct organisms like Cano's bee preserved in exquisite anatomical detail, but biological molecules such as dna appear to be largely protected...
...article in Thursday's Boston Herald, anonymous sources said they were certain that someone had introduced the substance, which was described as a liquid, resin-based adhesive, into the helicopter's fuel tank...
President Reagan got hoots when he once claimed that trees cause air pollution, but intrepid University of Florida researchers have now confirmed that the Gipper was onto something. A new study of terpenes, a component of the gooey resin in pine tree sap, shows that at least some trees actually do contribute to pollution by reacting with other pollutants and sunlight to produce ozone. While this is not yet cause for alarm, they add, the situation could get worse as temperatures rise because of the "greenhouse effect...