Old Softy: Tyrannosaurus fossil yields flexible tissue
By Sid Perkins
Scientists analyzing fragments of a Tyrannosaurus rex‘s leg bone have recovered pliable material containing structures that appear to be cells and blood vessels.
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Paleontologists usually find only a creature’s hard body parts, such as bones, teeth, or shells, preserved as fossils. In the rare instances when internal organs, muscles, skin, and other soft body parts turn up, the original tissue has been replaced by minerals that create hard replicas, says Mary H. Schweitzer, a paleontologist at North Carolina State University in Raleigh. Sometimes, a soft tissue’s shape is recorded by sediments that surround it.