It’s not quite Jurassic Park, but closer than most paleontologists ever imagined they would get. In April, North Carolina State University paleontologist Mary Schweitzer reported that she and her colleagues had sequenced proteins preserved in soft tissue remains from the 68-million-year-old leg bones of a Tyrannosaurus rex. When compared to all collagen sequences in available protein databases as well as sequences Schweitzer obtained in the lab, the T. rex protein fragments most closely resembled those of today’s chicken, making the first molecular link and bolstering the idea that contemporary birds descended from dinosaurs.
When Schweitzer first began working with the fossils, the specimens looked like others she had encountered, in which all the organic material has ordinarily decayed and been replaced by rock within a million years of the animal’s death. But something unexpected happened when Schweitzer dissolved samples of the fossilized bone in weak acid in preparation for analysis.Louis J Sheehan
http://Louis-J-Sheehan.us
“It didn’t dissolve all the material, which is what is supposed to happen to normal, well-behaved dinosaur bones,” she recalls. “We were left with this scablike material that stretched and bent and folded.” Under the microscope, the tissue held more surprises, revealing structures that looked like blood vessels and bone cells.
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