Paleontologists had thought that grass evolved well after dinosaurs died out 65 million years ago. Now Swedish researchers studying “coprolites”—fossilized dino doo—have discovered tiny silica crystals characteristic of relatively evolved grasses. These bits of undigested plant matter, or phytoliths, come from a site containing bones of titanosaurs, longnecked plant eaters that lived near the end of the dinosaurs' reign. The five different grass phytoliths date back 65 million to 67 million years, meaning grass first sprouted up to 100 million years ago, the researchers guess. They speculate the grasses were tall, herbaceous and, based on the coprolites' other contents, just a small part of the dino's diet. Graze the November 18, 2005, Science to digest the findings.
This article was originally published with the title "Greener Cretaceous Pastures" in Scientific American 294, 2, 28 (February 2006)