About the Fossil Tortoises
Referred to informally as “Tootsie” and “Peanut,” these tortoises are Stylemys nebrascensis. While this species is similar in some ways to modern tortoises, it lacked foreleg musculature for digging tunnels. These fossils are 34 million years old. Fossils from this species are regularly found in the South Dakota/Nebraska Badlands. Jim Caddell donated these specimens to the Heard in June of 2013. Preparation for displaying these fossils began in the lab in October 2013. After four years and more than 5,000 volunteer hours, they are ready for the museum floor.
What Makes This Exhibit Unique
The adult tortoise fossil on exhibit will be mounted much like an ‘exploded’ drawing with the three elements that make up a turtle (carapace, skeleton, and plastron) separated for visual study and examination. This "3D" example will provide a unique educational opportunity for teaching the anatomy of these unique reptiles.
This specimen also provides an opportunity to view a complete fossil Stylemys. This is rare for a number of reasons. Many Stylemys nebrascensis that are discovered do not include the skeleton. Additionally, the entirety of the fossil also comes from a single individual, which is a rare occurrence. Mineral deposits in the shell expand over time, fragmenting the shell. By the time the soil around the fossils erodes and the shell is visible at the surface, sometimes only fragments remain. Often, the tortoises were scavenged after death, leaving the remains in poor condition. Due to the weight (over 200 pounds) adult specimens are seldom collected.
Approximately half of the juvenile tortoise has been prepared and cleaned. The other half remains in its original condition allowing visitors to get a better sense of what the volunteers work on in the preparation process. For this reason, examples of the tools used will also be displayed to demonstrate and educate the museum visitors on the fossil preparation process.
About Turtles and Tortoises
Tortoises are amazing creatures and belong to the order Testudines, which dates back to the Triassic period. They have survived four mass extinctions, ice ages, and continental upheavals. In the vertebrate world, only eel and crocodilian species have a nearly equal longevity. After you have observed these two 34 million-year-old specimens, be sure to observe two modern species of tortoises, also on exhibit at the Heard.