Exhibits at the Tate

Dee the Mammoth and the Pleistocene Exhibit

Dee the Mammoth is an 11,600 year old Columbian Mammoth who lived in the American West during the Pleistocene, or Ice Age. 65 to 70 years old when he died, Dee is unique in both his advanced age and his completeness.

Dee was discovered in 2006 by a backhoe operator who was preparing an oil well pad site north of Glenrock, WY. The operator, Dee Zimmerscheid, knew that he had hit something big when several large white bones were churned up from under his machine. He called in his site supervisor, Bill Allen and together they decided that it was time to call in the land owners and the experts.

It was determined that the bones were from a mammoth and that more of the huge mammal was probably located below the surface. Dr. Kent Sundell recommended that the oil well be moved over about 100 feet and the oil companies that were involved agreed. Additionally, the Allemand/Byrd family who owned the land and thus the bones, generously donated the skeleton to the Tate Geological Museum.

During three of the next four summers, over 300 mammoth bones were recovered from the site. After recovery, the bones were transported to the museum lab to be cleaned and cataloged. Many of the bones were complete and identifiable, making the staff and volunteer’s jobs in the lab easier. The skeletons completeness enabled the the Black Hills Institute of Geologic Research to reassemble and mount the mammoth for display in the museum where it can be seen today.

The Pleistocene Exhibit, featuring Dee, informs visitors about Wyoming’s Pleistocene environment, introduces a few of Dee’s contemporaries and discusses the differences and similarities between mammoths, mastodons and elephants. Visitors can play the PSI (Pleisto-Scene Investigation) game to determine, on their own, how the mammoth died and follow the Timeline of Discovery for a quick view of the events leading up to and occurring after the skeleton’s discovery. Watch a video on mammoths or look at photos and home videos from the field as you learn about the life and times of Dee the Mammoth.

We have this cool time-lapse video provided to us by the Black Hills Institute of Geological Research of them working on mounting Dee’s bones in their warehouse in Hill City, South Dakota.

But wait… there’s more… a few questions on the subject…

How much of the skeleton is real?

Not all of the bones on the mammoth are real. The lighter, yellowish colored bones on the skeleton, such as the left leg and foot, are casts or copies. It was necessary to make casts of several bones because the originals were never recovered. 84 of the bones mounted on the skeleton are casts. Of those 84, 62 are foot and toe bones. The remaining 22 cast bones are from the leg, ribs, vertebrae and tail. A few other key bones have been cast and painted to resemble the original bones including the pelvis, skull and both tusks. In these cases the actual bone was recovered, but it was too fragile to mount in the exhibit. We believe that Dee is the largest and most complete mounted Columbian mammoth in North America.

What are tusks made of?

Mammoth, mastodon and elephant tusks are made up of dentin, a basic component found in all teeth. The dentin in the growth layers can indicate what their diet was, how healthy they were, when they were weaned, and even the time of year that they died. Baby mammoths had tiny milk tusks that erupted at around 6 months of age. They measured approximately 5cm (2 in.) in length and were replaced with permanent tusks by the end of their first year.
Mammoth’s tusks grew continuously anywhere from 2.5 cm to15 cm (1 to 6 in) a year. Growth occurred in the tusk socket and as much as a quarter of the tusk was embedded there. This means that the oldest layers of dentin, formed when the mammoth was young, were toward the tips of the tusks.

How do tusks grow?

Tusks are made up of a series of “ivory cones” that spiraled as they grew, creating the distinctive twist. It has been suggested that this twist is what allowed the tusks to grow to massive lengths (up to 4.88 m or 16 ft.) without creating excessive torque on the spine and skull.

The cones (photo to right is looking into the base of a tusk) that make up the tusks have been compared to growth rings in trees. By studying the rings (photo to left) or cones, the approximate age of the mammoth can be determined. However, this method cannot be used to determine their exact age since the tips are often worn down or broken off, effectively erasing the early years. Annual and weekly growth lines can be seen in the tusks. Under high magnification even daily growth can be seen. The color of the growth lines indicates the rate at which the dentin was deposited. A lighter shade equals faster growth and darker lines indicate slower growth.

Why study elephants?

Much about extinct species can be learned by studying the habits and behaviors of their living relatives. While elephants are not direct descendants of mammoths or mastodons, they are related, and physically similar. Elephants, mammoths and mastodons are all members of the order Proboscidea (pro-boSIH-dee-a) which includes over 150 species that originated during the last 50 mil-lion years. Proboscidea is Latin in origin and means “nose” or “long flexible snout”. Today this order is represented by the two living elephant species Loxodonta africana (African elephant) and Elephas maximus (Asian elephant ).

Elephants are the closest living relatives to mammoths, and scientists can infer possible mammoth behavior and herd structure by observing elephants. Scientists are able to use the information that they gather from such behavioral studies to develop hypotheses about mammoth behavior. They then support their hypotheses with skeletal evidence from discoveries such as Dee, The Mammoth Site in South Dakota, and the Waco Mammoth Site in Texas. Dee’s skeleton helps to corroborate the theory that many bull mammoths were loners, just as many bull elephants are. By studying his remains they can further support the idea that the average Columbian mammoth life span did not extend much beyond 70 years.

Death of a Mammoth

No one can be 100% sure how Dee died. While there are several hypotheses, the most probable one is that he was ‘neutralized by natural causes’. Dee was an extremely old mammoth. He had severe arthritis in his lower back, odd growths on his bones, a bone tumor, and several other problems that would have made it difficult to walk, move and chew. (The medical term used for these bony growths or bone spurs is spondylopathy which is a type of reactive arthritis.)

Additionally, Dee was using his sixth and final set of teeth. (See Mammoth Teeth for more information) He used his last set for as long as he could, however they were worn down so far that it would have been impossible for him to eat enough food to stay healthy. Eventually, he would have starved to death.

Radiocarbon Dating

Radiocarbon dating was used to determine the approximate date that Dee died, which was 11,600 (+/- 70) years ago. This dating method was developed in 1950 and is used world-wide to determine the age of organic-based materials. Organic materials are materials that were once alive, so radiocarbon dating methods can be used on, but are not limited to, wood, charcoal, seeds, plant materials, plant-based cloth, bone, ivory, shell and hide.
Radiocarbon dating measures two levels of carbon, carbon 12 (12C) and carbon 14 (14C), which is found in organic materials. 12C is a stable isotope, meaning that it remains at the same level after the organic material that produced the carbon in life stops producing it (i.e.: the animal died or the tree was cut down). 14C is not a stable isotope, it is radioactive or unstable, and will decay at a known rate. Scientists can determine the levels of 14C and 12C in a sample, and compare the proportion of the two carbons to a modern sample, which will give an approximate date of death. The date is given plus or minus (+/-) a variable number of years, allowing for possible uncertainties in the measurement.

Working together

Continental Production Company, Mountain West Energy, LLC, and Nerd Gas Company, LLC, along with Discovery Resources, LLC, Basic Energy Services and the Allemand family all made this ‘mammoth-sized’ exhibit possible. Based upon Dr. Sundell’s recommendation, the oil companies decided that it would be in the best interest of the community to move the location of the well to facilitate the mammoth dig. Both the oil companies and the community benefited from this historic event.

Through conscientious and community-minded decisions, these companies allowed the Tate Geological Museum and Casper College to step in, collect and preserve the specimen. It is also due to the forethought and cooperation of the Allemand family and their generosity in donating the mammoth bones that Dee the Mammoth is here on display at this museum.

Dino Den

The Dino Den is located in the front, northeast corner (opposite the gift shop) as you enter the museum. Created as a dinosaur discovery zone, it gives kids room to play and investigate on their own. The Dino Den features coloring, puzzles, a mineral ID game, fossil rubbings, touchable fossil casts and dinosaur themed toys for all ages. Stop by to play and learn anytime!

Hall of Minerals

The Mineral Exhibits line the north wall of the museum and cover mineral types, diagnostic mineral features, silicates and non-silicates, Wyoming’s extractive resources and the state gemstone, Jade.

Walk Through Time

The Walk Through Time, located along the back (west) wall of the museum takes visitors back through time from the Holocene hunter and gatherers of North America right back to the formation of the earth. Along the way there are several drawers with touch samples which allow visitors to interact with the fossils as they move back through time. Be sure to look for the plant fossils, the T.rex tooth, and the trilobites along the way.

Mesozoic Marine

The Mesozoic Marine exhibit exposes the underwater world that existed here in Wyoming during much of the Triassic, Jurassic and Cretaceous. Wyoming’s warm, tropical seaways were home to a plethora of marine animals and some plants, including ammonites, belemnites, star shaped crinoids, ichthyosaurs, mosasaurs and hybodont sharks. Of particular interest (here at the Tate Museum, anyways) is the Sundance Plesiosaur, Tatenectes laramiensis, named for the founders of the museum Marion and Inez Tate.

Mesozoic Terrestrial

It was the time of the dinosaurs. The Mesozoic Era is usually better known by its three periods, the Triassic, the Jurassic and the Cretaceous. The Mesozoic Terrestrial area highlights the massive size of the dinosaurs as well as a few of the features that made some of them terrifying and so fascinating. Stand next to a torvosaur leg, see how big an Apatosaurus foot really was, check out the size of an Allosaurus claw and have a face-off with Stan the T. rex!

The Pterosaur Ptracks exhibit introduces the pterosaurs that called Wyoming home. Jurassic pterosaur footprints have been discovered near Alcova Reservoir and models in the display have been reconstructed (to scale) from these footprints. These footprints also helped to solve the riddle of how pterosaurs walked when they were on the ground. Did they walk on two feet? On all four? Like a dog or a bat? Visit the museum to find out.

Eocene of Wyoming

The Eocene Epoch had a warmer, wetter environment and large variety of animals flourished. The landscape was full of archaic mammals that were vastly different from mammals today. Conversely, the reptiles were amazingly similar to their modern counterparts. The Eocene display features a fossilized crab, turtles, fish, mammals, birds and feathers, crocodiles and alligators and plant pieces many of which were found in Wyoming. Learn about life after the dinosaurs, and find out for yourself how similar the Eocene reptiles were to modern reptiles.

Oligocene/White River of Wyoming

The Oligocene Epoch came after the Eocene. By this time dinosaurs had been extinct for about 30 million years, and mammals ruled the earth. The variety of fauna that lived during this time is well preserved in the White River Formation of Wyoming which is known for its preservation of mammals including oreodonts, titanotheres and predators such as the entelodont. See if you can find the skeleton of the three-toed horse and discover how different it is from the modern horse. How many differences can you find?

Prep Lab

The prep lab is where the specimens are cleaned and made ready for exhibit in the museum gallery. Our prep lab is visible to the public via a sliding glass window, so you can see what we are working on. Feel free to ask our staff and volunteers questions about the current projects that they are working on in the lab.

Rex Annex & Lee Rex

Want to see a real T. rex? Ask at the front desk for a tour of our new Rex Annex. The annex was dedicated in May 2017 to house the articulated skeleton of Lee Rex.  Lee is in an 18 x 8.5 foot concretion and was diligently worked on for three years by a dedicated group of volunteers.  It is the first T. rex found in Wyoming to stay in the state.