• Temples and Towers of the Virgin

    Zion

    National Park Utah

There are park alerts in effect.
show Alerts »
  • Fire Restrictions

    Fire restrictions prohibiting campfires and charcoal fires in Watchman and South Campgrounds are in effect. More »

  • Trail Closures

    Monday to Thursday through 9/18: The East Rim Trail from Weeping Rock to Echo Canyon, including Hidden Canyon, is closed.
    The Hidden Canyon Trail is closed through 9/18. More »

Mystery Tooth

Mystery Tooth

Mystery Tooth

The importance of paleontological collections, preservation, and research is underscored by the revelations they provide. When the tooth specimen pictured on the right was collected, it was believed to be perhaps the oldest evidence of an ornithischian (meaning “bird-hipped”) dinosaur in Utah, and the only herbivorous dinosaur known from the Triassic Period of Utah. However, a 2004 excavation of a fossilized skeleton at Petrified Forest National Park, Arizona, containing the same type of tooth, proved that Zion’s tooth wasn’t from a dinosaur.

Before discovery of the Arizona fossilized skeleton, the Zion species was one of several Late Triassic fauna identified only from its teeth. The teeth look like those we know from herbivorous dinosaurs ancestral to Stegosaurus and Triceratops that roamed the earth in the Jurassic and Cretaceous Periods millions of years later.

Based on the newest Arizona skeletal discovery, Zion’s tooth specimen belonged to an herbivorous or omnivorous crocodilian ancestor living a mostly terrestrial life in Late Triassic uplands. During this time, developing theropod (“three-toed”) dinosaurs may have hunted Zion’s crocodile ancestor as one meat source. As new southwestern fossil discoveries occur, our understanding of Zion’s past fauna evolves, just like the dinosaurs did.

 
Revueltosaurus
Revueltosaurus
 
Return to the Fossil Collections main page

Did You Know?

Tarantula

During the summer or fall, you may see a tarantula crossing a road or trail in Zion National Park. But don’t be frightened-- tarantulas are actually amazing arachnids--gentle, basically harmless creatures that have suffered a bum rap. More...