Revealed in fossil poop: dinosaurs ate
Nov. 17, 2005
and World Science staff
Scientists say they have found the first evidence for grass-eating dinosaurs. But perhaps unsurprisingly,
they say grass doesn’t seem to have been the reptiles’ favorite food.
Researchers found tiny bits of silica, a glass-like substance produced by grass,
in the fossilized dung of sauropod dinosaurs.
Sauropod dinosaurs, huge plant-eaters with small heads and long necks and tails, are the largest known land animals.
The dinosaurs in this study lived in present-day India about 65 million years
ago, shortly before dinosaurs died out.
This finding will help scientists understand the evolution of grasses and dinosaur ecology, the
Dinosaurs aren’t traditionally considered grass-eaters simply because grass
wasn’t thought to have been common during dinosaur times, researchers
Thus, “dioramas in museums have long depicted dinosaurs as
grazing on conifers, cycads, and ferns in landscapes without grasses,” wrote
researchers with the National Museum of Natural History in Washington, D.C., in
the Nov. 18 issue of the research journal Science.
But the study, published in the same issue of the journal, seems to have changed
that view, they added.
The study, by Vandana Prasad at Birbal Sahni Institute of Paleobotany and Paleozoology in
Lucknow, India, examined distinctive silica structures called phytoliths. They’re known to form in the cells and tissues of grass and other plants.
The varied grass-specific phytoliths found in the fossilized dinosaur dung
suggest grass had evolved to be considerably more diverse by that time than is generally believed, the researchers said.
But grasses don’t seem to have beeen the primary food of sauropod dinosaurs,
the researchers said. That conclusion was based on the amount of grass phytoliths found in the fossilized dung.
Certain early mammals with enigmatic teeth that appear suited for handling abrasive materials may have also eaten grass, according to the authors.
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