Episode 14 – The Gray Fossil Site

Find Episode 14 on PodBean, iTunes, or Stitcher!

Our most recent episode talks about one of our favorite dig sites, the Gray Fossil Site. Not only is this site where the two of us got a lot of our hands on experience with paleontology, but it is also a fascinating fossil deposit.

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History of the Site

The Gray Fossil Site and Natural History Museum is a small museum located in the city of Gray in East Tennessee, and built upon a significant fossil deposit unlike many others.

File:Front of Gray Fossil Museum.jpg
A front look at the museum during its grand opening. Image from Wikimedia Commons, by Magnus Manske.

This site was discovered in 2000 while a road crew was digging through a hillside to extend a road. They soon noticed the bones preserved in the clay of the hill and road work was halted so the road could be redirected.

A few years later a museum was built on the site. Since then the site has been managed by the Geosciences Department of East Tennessee State University (ETSU). The professors, students, staff, and volunteers continue to excavate the fossils there, which are then preserved and stored in the museum’s on site lab and collections.

A look into the lab at the museum while Shawn (left), the head preparator, and David (right) do some prep work. Image taken by Sandy Swift.

Both of us actually worked at the museum as educators while we were at ETSU. This was our first joint foray into paleo-education!

Prehistory of the Site

This fossil deposit was created by a limestone sink hole that formed a pond in a forested area between 4.7 and 7 million years ago, placing it at the boundary of the Miocene and Pliocene Epochs. This created a watering hole for all kinds of animals in the area at that time.

File:Cover-collapse sinkhole.png
Sinkholes are formed as water dissolves limestone and creates a cavity that eventually collapses. Image from USGS.

The sinkhole is fairly large, covering about 4 acres on the surface and over a 100 feet deep at the lowest points. This would have been a very calm body of water whose depths provided the perfect environment for fossilization.

The Fossils

This habitat was very rich and sported many species of animals and plants that have been preserved in the clay, including many species one would expect to find in a pond in Tennessee, such as turtles, birds, snakes, and fish. But other residence are not as familiar. Among these are alligators, rhinos, mastodons, and saber-toothed cats.

File:Top and bottom shell fossil Cf Chrysemys picta 01.jpg
Turtles are one of the most common fossils found at the site. Here we see a complete painted turtle shell from the collections. Image from Wikimedia Commons, by TCO.

The site also has had multiple new species identified there. Due to this being one of the few fossil deposits from this time period on the East Coast, many of these animals are being discovered for the first time. The most famous is the new species of fossil red panda, which today are only found in Asia.

File:RedPandaFullBody.JPG
This is a modern Red Panda. The fossil panda from Gray is about 50% larger and seemed to spend more time on the ground and eating small animals! Image from Wikimedia Commons, by Greg5030.

There is still much to learn from this site as only about 1% of the total clay deposit has been excavated since digging started in 2000. As the guests on our tours always liked to say, “Hey, at least you have job security.”

This is what a typical pit looks like after a summer of digging at the site. The flags denote locations where fossils are or were located. Image taken by David Moscato

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