Saturday, May 21, 2011

Jefferson's Ground Sloth

The year was 1796.  Thomas Jefferson had not yet been elected as Vice President of the new country...but he did receive an interesting package from (then) Greenbrier County, Virginia.  The package, sent from Colonel John Stuart, contained the fossilized bone fragments of a femur, ulna, radius, and several large claws, that were allegedly found in a Greenbrier County cave.

The following year, Jefferson, now America's Vice President, theorized in a paper that the bones came from a giant lion that he named Megalonyx (giant claw).  He believed that the creature in question WAS still alive and well, and could be found in the western Virginia wilderness.

Today, we know the creature as Megalonyx jeffersoni...or giant ground sloth.  This beast was 8-10 feet long, weighed up to 800lbs, and lived during the Illinoian Period.  Also, up until recently, it was believed that the fossilized bones came from a cave in Greenbrier County known as Organ Cave.  However, in 1993, pieces of a Megalonyx jeffersoni scapula were found in nearby Haynes Cave, in neighboring Monroe County.  At the time of the discovery, the cave WOULD have been in Greenbrier County, as Monroe wasn't formed until later. Further, documentation shows that the bones were found by saltpeter workers on land owned by a Frederic Crower.  The Haynes cave WAS used in saltpeter work, while the owner was named Frederic Gromer, theorized to be a misspelling.

In 2008 the Megalonyx jeffersoni bones that were discovered were designated as WV's Official State Fossil and are part of the collection owned by Prehistoric West Virginia.

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  1. I wonder if this creature is the same as the fossilized giant sloth found in the Grand Canyon Caverns near Peach Springs, Arizona?

    Cynthia Parker

    1. I'm not sure, Cynthia. I'm guessing they have to be at least in the same general family. How many giant sloth species could we have in this country? lol