A new HUGE discovery…and it is so OLD! By: Dr. Jim Mead
There is a great, highly-experienced group of Science Associates who advise and collaborate with the researchers here at The Mammoth Site. We are really lucky to have this group of researchers – some who live right here in the Hot Springs area while others work in institutions as far away as Colorado, Wyoming, Alberta, Tennessee, and Florida. Although The Mammoth Site centers its research on the late Quaternary time period (the most recent 2+ million years) from a global view, the institute also focuses on all types and ages of fossil proboscideans which include the mammoth right here in Hot Springs.
About four weeks ago Dr. Blaine Schubert (Mammoth Site Science Associate and the Executive Director of the Gray Fossil Site & Museum at East Tennessee State University), Dr. Steve Wallace (Wally; Excavation Director, Gray Fossil Site), and museum staff were working at the late Miocene-age (7.0-4.5 million years old) locality just 20 minutes from the university in eastern-most Tennessee and came across some tusk fragments! Blaine, Wally, and I have been working on various vertebrates from that locality – red panda, Gila monster lizard, alligators, tremarctine bears, turtles, snakes, among many others. Finding fragments of a tusk obviously means that there is some sort of early proboscidean in that remnant-sinkhole fossil site. Take a look at the photo of the long, straight tusk – it will be over 2.5 m (8 ft) long when complete. It is not highly curved such as the mammoth tusks we have here in The Mammoth Site. Following the tusks back into the excavation wall, staff members Shawn Haugrud and Brian Compton located the skull and lower jaws. Further excavation allowed them to discover the articulated neck vertebrae…and it keeps going. There is more of the animal but under lots of in-situ sediments yet to be excavated!
Look at the teeth. Note the cusps, ridges, and valleys – these are buno-lophodont teeth. These are not like the flat-grinding teeth of our mammoths or today’s elephants. We are not sure yet of a detailed identification but we do know that these teeth are from a mastodont – an extinct form of distant elephant relative. You can see in the photos that we are just now getting the skull and jaws removed – they are huge.
Interestingly, very little is known about North American Miocene proboscideans so any new information is important. Almost nothing is known about the Miocene of eastern North America so the Gray Fossil Site is exceedingly important.
Researchers at The Mammoth Site continue to collaborate with colleagues across the continent and around the world to better understand evolutionary and environmental changes through time – especially with the proboscideans and our home here in the Black Hills of South Dakota.
Keep in touch with The Mammoth Site because we continue to branch out in our relationship with our peers – other fossil natural history museums such as the Gray Fossil Site. We hope that soon you can be standing in The Mammoth Site on the edge of the bone pit and internet link to the Gray Fossil Site (http://www.etsu.edu/naturalhistorymuseum/) to see what they too are unearthing that day!
Oh – Just the other day the Gray Fossil Site crew located a younger mastodont not far from the adult tusk shown here – figure out that story!! More on that soon too!
Skull of an early form of mastodont from the late Miocene of eastern Tennessee. The skull is positioned on its right side – it would be looking to the left. The eye would be just below the blue pad. The lower jaw is still exposed below the plaster jacket covering the skull. You can see the lower cheek teeth exposed. The tusks projected to the left of the skull. There are also lower-jaw tusks, much smaller than the upper tusks (mammoths and elephants do not have these). Tusks have already been removed from the excavation. Note the long, acute angle that the lower jaw takes at the chin (left end of the jaw just before the first cheek tooth) – this is another feature that mammoths do not have.
Here is a close-up, side view of the upper cheek teeth. Note the cusps, lophs, and valleys on these mastodont teeth. These teeth do not grind grasses and sedges as do mammoths but chomp up woody plants while browsing in woodlands and forests.