The largest and oldest fossil of a Tyrannosaurus rex, nicknamed "Sue" after its discoverer, was unearthed in 1990 near Faith, South Dakota. Today, Sue resides in the Field Museum in Chicago.

Photograph by Fritz Geller-Grimm, courtesy Wikimedia. This file is licensed under the Creative Commons Attribution-Share Alike 2.5 Generic license.

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  • On August 12, 1990, amateur paleontologist Susan Hendrickson unearthed the first three fossilized bones of what would turn out to be the largest, oldest, and most complete Tyrannosaurus rex ever discovered. Hendrickson stumbled upon the fossils by accident while excavating near Faith, South Dakota, for another dinosaur. Hendrickson’s discovery was nicknamed “Sue” in her honor, but paleontologists aren’t sure if Sue was a male or female. Sue’s fossilized skeleton is about 12.3 meters (40 feet) long and 4.3 meters (14 feet) tall at the hips—the specimen is not displayed standing upright, but crouching parallel to the ground.

    Sue is remarkably well-preserved, with more than 80% of its fossilized skeleton intact. Paleontologists say the specimen is so complete because it was covered by water and mud quickly after its death. This prevented scavengers from carrying away the bones, and wind and water from eroding them.

  • Term Part of Speech Definition Encyclopedic Entry
    amateur Adjective

    person who studies and works at an activity or interest without financial benefit or being formally trained in it.

    dinosaur Noun

    very large, extinct reptile chiefly from the Mesozoic Era, 251 million to 65 million years ago.

    paleontologist Noun

    person who studies fossils and life from early geologic periods.

    parallel Adjective

    equal distance apart, and never meeting.

    scavenger Noun

    organism that eats dead or rotting biomass, such as animal flesh or plant material.

    Encyclopedic Entry: scavenger
    skeleton Noun

    bones of a body.

    specimen Noun

    individual organism that is a typical example of its classification.