Stylemys: A Fossil Tortoise from the White River Badlands

by Broden William Dymond

Stylemys was a tortoise that lived about 33 million years ago, during the Oligocene. Stylemys lived on land, rather than land and water. Fossils of Stylemys have been found in rocks in North Dakota, nearby states, Asia, and Europe. Stylemys was first described by Joseph Leidy, a fossil expert, in 1851. He was one of the important scientists in America at the time. This tortoise fossil was found in the Brule rock formation in the White River Badlands of South Dakota. 

Fossilized carapace of Stylemys nebrascensis.
Found in the White River area of North Dakota.
Photo by B. Dymond. From the collection of S. W. Veatch. 

During this Oligocene, North Dakota was a treeless plain covered in shrubs, plants, and some types of grass. It rained sometimes and the temperature was mild.

Stylemys had a domed carapace (upper shell) and a plastron (lower shell) for protection. Their limbs were made for living on land. Stylemys was similar to Gopher tortoises that are living today and they probably ate plants. The legs of Stylemys were different from Gopher tortoises so they probably did not dig tunnels. Turtles and tortoises at this stage in evolution survived well and have not changed much since that time.

The fossil of this Stylemys is slightly crushed with scratch marks near the tail and seems to have the mark from a tooth. Here is what might have happened to this Stylemys:

‘’One day, the tortoise was just walking along. He ate some grass just a little bit ago. He heard something behind him. It was a prehistoric crocodile! When the tortoise saw the crocodile, it started to run. The crocodile was faster, and it caught up to the tortoise. It bit and scratched the tortoise, but the tortoise fell into the mud. It was stuck so the predator could not get to it. The crocodile wanted the tortoise so bad but he noticed a sand storm coming and ran for safety. The end.”   It was from this comic:

Artwork by the author.

About the author:   Broden Dymond is an active Pebble Pup in the Grand Traverse Area Rock and Mineral Club. He is 10 years old and is in the 4^th grade.

 

Pups Celebrate National Poetry Month

The Grand Traverse Area Rock and Mineral Club’s Pebble Pups and Teen Earth Science Scholars Celebrate National Poetry Month

Artifact
Green as emerald
Ancient civilization
Sacred rituals

    By Nathan Peters, 10th grade

Photomicrograph of a chrysoprase bead made
by the ancient Pyu civilization.
This artifact measures 9.5 mm across.
Photo © Steven Veatch.

Puddingstone
I am forgotten
But not lost—formed by pressure
A story of the past

    By Tim Bashore, 10th grade

A puddingstone found in a Michigan
 farmer’s field. Photo © Steven Veatch.

Restart
An asteroid hit
The Triceratops and others died 
Life started again
    By Bo White, 1st grade

A Triceratops out for a
Mesozoic stroll. Sketch by S. W. Veatch.

Sabertooth
Saber is coming!
Mammoth gets stuck in the tar 
Saber eats the mammoth.
    By Clayton Sedlacek, 3rd grade

A sabertooth cat stalks prey.
From the S. W. Veatch postcard collection.

Flight
It flies with its wings
The Archaeopteryx takes meat
Dinosaurs are dead
    By Brady Sedlacek, Kindergarten

An Archaeopteryx gets ready to fly.

Sketch by S. W. Veatch.

Amethyst
The color purple
This amethyst is bumpy
To hold and to touch
    By Scarlett Sedlacek, 2nd grade

Formerly known as “grape agate,”
these specimens are now considered to be amethyst,
not chalcedony. Source: Mindat.org. Photo © Steven Veatch.

The Grand Traverse Area Rock and Mineral Club’s First Pebble Pup Class Meets in March

In recent years, there has been a growing interest in geology and rockhounding among people of all ages. Whether it's the thrill of finding a mineral, rock, or the satisfaction of identifying a fossil specimen, there's something about rockhounding that captures the imagination.

Nowhere is this more apparent than in a new rockhounding class for children, the Pebble Pups, which has been a smashing success. The class, which is taught by passionate and knowledgeable instructors, has attracted a wide range of students, from 5 years old to 16 years old, who are eager to learn about the fascinating world of geology.  Two groups comprise this program. Elementary students are Pebble Pups. Middle school students and high school students participate as Earth Science Scholars. The older students work on research projects and help work with the younger students.

The first class met March 15, 2023. There were 5 Pebble Pups, 2 teenage Earth Science Scholars, 3 parents, 3 pup teachers, and 3 adult visitors. The Pebble Pup classes cover a range of topics, from basic geology and mineral identification to more advanced concepts like plate tectonics and geological time. Through a combination of lectures, hands-on activities, and field trips, students are able to deepen their understanding of the subject and develop a love for rockhounding that will stay with them for years to come.

Melanie Ackerman and Steven Veatch begin the first Pebble Pup lesson.
Pebble Pups meet from 5: 30 to 6:10 pm, the same night
the club meets at the VFW. Photo by Shelly Veatch.

One of the reasons the class has been so successful is the enthusiasm and dedication of the instructors. With years of experience in the field, they are able to share their knowledge and passion for the subject with their students, making the class engaging and informative. The instructors are Steve Veatch, Melanie Ackerman, and Michelle Peters. Nathan Peters, who participates as an Earth Science Scholar, is the program assistant. 

Melanie Ackerman is teaching the group how to write a short poem a
bout a rock, or mineral, or even a fossil. This mixes writing with science
to produce something artful, a poem. April is National Poetry Month
and the pups will participate. Photo by Shelly Veatch.

Another factor contributing to the success of the class is the way it is structured. By combining traditional classroom learning with hands-on activities and field trips, students are able to experience the subject in a variety of ways and develop a deeper understanding of the material.

But perhaps the most significant factor in the success of the class is the students themselves. With their natural curiosity and willingness to learn, they have embraced the subject and are eager to explore the world of geology and rockhounding.

For these students, the class is more than just an opportunity to learn about rocks. It's a chance to connect with the natural world, to discover the beauty and complexity of the earth, and to develop a sense of wonder and appreciation for the world around them.

As the success of this new rockhounding class demonstrates, there is a growing interest in geology and rockhounding among young people. By providing them with the tools and knowledge to explore this fascinating subject, we are helping to cultivate the next generation of rockhounds, and that's something for the Grand Traverse Area Rock and Mineral Club to be proud of.