An intact tusk of a Columbian mammoth has been discovered in Madison County, Mississippi. It is the first complete mammoth tusk discovered in the state and dates to the last Ice Age (between 10,000 and 20,000 years ago) when the 15-foot-tall Proboscideans roamed the Mississippi prairie.
Mastodon remains are fairly common in Mississippi, as they were widespread across the territory. They were browsers (like deer) and were able to find food in all kinds of environments. Mammoths, on the other hand, strictly grazed on open grassland so they stuck to the Jackson Prairie of central Mississippi. Mammoth teeth have been found there, marking the grounds they used to roam, but their massive tusks have proved elusive.
Finder Eddie Templeton, an avid fossil and artifact collector, spotted the tusk in the bank of a small creek. He immediately notified the Mississippi Department of Environmental Quality’s Office of Geology and the Mississippi Museum of Natural Science who went to the find site that same day. The tusk was partially exposed above the water, and in danger of drying out in the blazing afternoon sun if the team didn’t excavate and remove it promptly.
With Eddie’s help, the team removed the clay-heavy sand from around and under the tusk, exposing its full seven foot length. Most of the mastodon tusks that have been found were just fragments, making this deposit extremely rare. The tusk was photographed and covered with aluminum foil to protect and prepare the surface for plastering. The tusk was then covered in burlap strips soaked in wet plaster to encase the heavy fossil before transport.
While the plaster jacket cured and dried, the team studied the details of the depositional environment recorded within the sediments exposed at the outcrop that the mammoth’s tusk was deposited in. The base of the massive tusk was lying almost upright and at an angle in the stream alluvium with a portion of it lying directly on top of the underlying marine Eocene sediments of the Yazoo Formation, just as it came to rest before burial. Our field scientists interpreted the mammoth tusk specimen to be leaning up against the edge of an ancient sandbar of a stream while a portion of it rest on the floor of stream channel. This would have been just before it was completely covered with alluvium entombing the fossil, possibly the result of a storm resulting in a major flooding event. The animal likely had died nearby, and its remains were then carried along the stream’s channel.
Studying the nature of the sediments exposed at the outcrop also gave our team of scientists some interesting information. The channel gravels preserved in the basal part of the alluvium is dominated by the mineral quartz with a minor amount of chert clasts. The fossil is located within the watershed of the Big Black River, and Quartz gravels like that are more reminiscent of the alluvium of the Pearl River as it crosses the Jackson Prairie region. The thick alluvial plane sediments deposited above the fossil are loess-derived silt. Loess is a wind-blown glacial silt that forms thick deposits across much of the upland terrain in western Madison County.
Once the plaster jacket containing the fossil tusk dried, it was carefully lifted onto a makeshift gurney fashioned from an ATV ramp. The fossil specimen in the jacket weighed about 600 pounds. It was then slowly maneuvered up a 50 foot, nearly vertical, bluff and onto a truck where it was delivered to the Mississippi Museum of Natural Science for further curation and careful study.
The tusk is now in the care of paleontologist George Phillips who has removed the plaster jacket to allow the tusk to dry. It will then be stabilized and preserved by injecting an adhesive into the mineralized ivory. The process is a slow and painstaking one, but when it is complete, the mammoth tusk will go on display at the Mississippi Museum of Natural Science.
* This article was originally published here
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