Vampire' dinosaur preferred plant diet

A dwarf dinosaur weighing less than a modern house cat had a sharp beak and fangs like a vampire but was a plant-eater, a U.S. paleontologist says. The single specimen of the new species was originally chipped out of red rock in southern Africa in the 1960s but lay mostly unexamined in a fossil collection at Harvard University until Paul Sereno, a paleontology professor at the University of Chicago, took another look. Pegomastax africanus -- "thick jaw from Africa" -- has a short parrot-shaped beak up front, a pair of stabbing canines, and tall teeth tucked behind for slicing plants that operated like self-sharpening scissors, with shearing wear facets that slid past one another when the jaws closed. "Very rare," Sereno said, "that a plant-eater like Pegomastax would sport sharp-edged, enlarged canines" like a vampire. While some paleontologists have argued consuming meat or at the least insects was a good part of the creature's diet, Sereno argues self-defense and competitive sparring for mates is more likely their role. Such pint-size early herbivores spread across the globe 200 million years ago, Serena said, and although virtually unknown to the public, "Pegomastax and kin were the most advanced plant-eaters of their day," he said.