Not only does the news add heat to a long-simmering debate over whether dinosaurs were coldblooded or warmblooded, but it could completely revamp the way scientists collect and examine fossils. Internal organs, once mistaken for rubble and tossed aside, may hold the key to reconstructing a portrait of life in the Mesozoic era. Hammer suspected that the rusty concretion in the chest cavity was a mineralized cast of the heart, but to confirm this he relied on Andrew Kuzmitz, a doctor and amateur paleontologist. Then experts at North Carolina State University fed the film into a computer to generate a rotating virtual 3-D model. The model also showed a single aorta looping out of the organ, a finding that stirs the debate over whether dinosaurs regulated their own body temperature or relied on sun and shade.
Warmblooded animals have one aorta while coldblooded creatures like crocodiles have two.
Members of the coldblooded camp say a second aorta may have just worn away. Why the heart fossilized is not clear, but researchers propose that iron in its muscular walls helped to precipitate a mineral, called goethite, to replace the tissue with a rocky mold. The beast was probably buried rapidly in a flash flood, concealed from scavengers and left to petrify intact. An abdominal mass, soon to be analyzed, could be the template of another organ. Paleontologists have unearthed vestiges other than bone before, such as nails, feathers, and cartilage.