What The Fossils of Makoce Sica (Badlands) Tell Us

Overview 

Lesson Name: Badlands Fossils Through Time

Grade Bands: 3-12

Keywords: Natural Selection, Adaptation, Biogeology, fossils, habitats, geologic time scale, OSEU

Time: 1- 8 periods. Note: the lesson below uses a jigsaw method to compress the activities into fewer periods for older students. For a more robust experience, the entire class can complete each jigsaw section over several days to allow for a deeper, iterative discussion of changes in animals and climate over time.

Background

Badlands National Park is a beautiful location known for its stunning geology. The park's geology covers two distinct periods: the late Cretaceous period, about 65 to 75 million years ago, and a stretch of the Paleocene period ranging from the Eocene epoch starting around 39 million years ago to the Oligocene epoch, ending in the Badlands approximately 23 million years ago.  Each of these periods is characterized by very different geology. During the Cretaceous, a warm, shallow ocean was expanding and contracting over North America's center. During the Paleocene (the Eocene-Oligocene epochs), the world was slowly cooling, and the environment in the Badlands changed from a hot forest to a cooler savannah. This cooling changed the plant communities and, by extension, the animal communities. 

Different plants and animals characterize each period. In this lesson, we have chosen to focus on four specific prehistoric animals, each of which tells us something significant about the history of the Badlands. We start with a contemporary animal, the buffalo (bison), as an entry point into the lesson and work backward through time. Other animals profiled are

• Oreodont. The oreodont is found through almost all the layers of the park’s geology except for the Cretaceous (earliest and lowest) layers. This discovery shows us that some animals could survive the changes that were occurring… until they couldn’t.

• Brontothere and alligator. These fossils are found only for about 4 million  years , contrasting with the oreodont found for about 7.8 million years. In addition, the alligator helps us understand that Badlands was a very different environment 35 million years ago.

• Mosasaur. The mosasaur, a marine mammal with flippers, helps us understand that the Badlands was once covered in water during the Cretaceous period.

Another essential idea presented throughout the lesson is that fossil teeth tell us about the animals. We have profiled two herbivores (oreodont and brontothere) and two carnivores (alligator and mosasaur).

In this lesson, students will create a timeline of animals found in the Badlands from the present to 75 million years ago. They use notice and wonders to engage with phenomena and will read articles to answer some of their wonders. Students will understand that fossil teeth provide essential information about animals. They will understand that the climate of the Badlands has changed over time, and the animals that lived there have changed in response. Students will apply their understanding by drawing dioramas and writing an explanation of the scene and information about the animals’ teeth. Students will analyze the timeline to understand the presence of animals in the Badlands. Students will understand that Lakota people knew about fossils and had their own stories about them.

Learning Goal (What students need to learn)

• Animals adapt and change based on their environment, or they die. 

• Fossils provide us with information about past plants and animals and the environment.

• Plants and animals change in response to the environment changing.

• When the environment changes, some animals die, some survive, and some thrive.

• Native Americans have different views about fossils than what we are taught in Western science. 

• Native Americans know and understand ancient animals that predate the “discoveries” of non-Native scientists. 

Success Criteria (How students know they’ve reached the learning goal)

• I can create a timeline that shows evidence of animals long ago. 

• I can compare and contrast animal traits in the present with traits from animals in the past. 

• I can explain how animal traits describe the environment in which the animal lives.

• I share my ideas about Native American perspectives on fossils and science. 

Materials and Media 

• Timeline printout & timeline instructions

• Cutouts 

• Worksheets (Grades 3-5). 

  • Buffalo & oreodont student diorama

  • Brontothere and alligator student diorama

  • Mosasaur student diorama

• Sketchfab account

• Articles: 

  • Grade 3-5

  • Grade 6-12

• Slide decks

Lesson Outline 

Preparation 

• Create a sketchfab account.

• Prepare the timeline.

• Prepare the articles for students to read (print or post)

• Prepare the slide decks.

• Print cutout page.

• Prepare student diorama worksheets (Grades 3-5)

Engage 

• Show students the skulls of the bison and oreodont individually on Sketchfab. For each skull ask the students what do they notice? What do they wonder?

• Show the skulls side by side using the slide deck. Have students compare them. What are the similarities? What are the differences?

• Return to the sketchfab images and have students compare the teeth of the two skulls. Tell students that scientists can tell what fossil animals ate by the shape of their teeth. Herbivore front teeth are used for grabbing plants while their back teeth are for grinding the plant matter. There is often a space between front and back teeth. Carnivores front teeth are large for grabbing prey that might escape. The back teeth are sharper and pointed.

• Discuss what bison eat (vegetation). Explain that scientists believe oreodonts ate vegetation as well. Find similarities and differences between bison and oreodont teeth. 

Explore 

• Tell students that in addition to animal fossils, paleontologists use fossils of plants to understand the habitat and climate conditions of the past. Plants can tell us a lot about temperature and precipitation as plants have different requirements. For example, a cactus and a palm tree grow in different environments. This information about the plants and climate is used by artists to create dioramas.

• Tell students they are going to study dioramas of Badlands animals, examine photos of their skulls and teeth, and read articles to learn more about Badland animals.

• Have students work in pairs or small groups. Assign each group a fossil to study. Provide each student a cut out sheet of the different animals to make their dioramas. Younger students might need the diorama backdrop while older students can use blank paper. Provide the following to each group:

  • Oreodont

    • Slide Deck (habitat and skull slides)

    • Articles: Grades 3-5, Grades 6-12

    • Diorama backdrop 

  • Brontothere and alligator

    • Slide Deck: Brontothere and Alligator habitat

    • Slide Deck: Brontothere and Alligator skulls

    • Articles: Grade 3-5, Grades 6-12

    • Dioarama back drop

  • Mosasaur

    • Slide Deck: Mosasaur habitat and skull

    • Articles: Grades 3-5, Grade 6-12

    • Dioarama back drop

• Use the prompt: Tell me about your animal and what kind of habitat it lived in to have students make a claim about their animal.  Have students reference the evidence found in the painted diorama habitats in the slide decks and the information in the articles to support their claim. Use Dioramas to assess learning. (See the next section to help evaluate student work).

Explain 

• As a class, review the fossils, habitats and food preference.

  • Oreodonts - warm humid forests to cooler open savannah/scrublands. Plant eaters. (Herbivores)

  • Brontotheres and Alligators - warm humid forests. The brontothere was a plant eater (herbivore) , the alligator a meat eater (carnivore)

  • Mosasaur - Aquatic environment caused by the Western Interior Seaway. Meat eater. (Carnivore)

• Tell students you are going to place the dioramas or cut out fossils along the timeline. Review the timeline noting that this period covers the geology found in the Badlands from present to 75 million years ago. The geologic timeline of the Earth is much longer. Help younger students understand the timeline as a reverse number line. (See timeline)

  • Start with the bison, a contemporary animal. Mark about ¼ inch on the right side of the box labeled 1 on the page Today to 5 million years ago. This represents the approximate amount of time bison have been on the grasslands. See picture below. 

  • Oreodonts - mark off 26.8 million to 38 million years ago on the timeline. Place the students' dioramas in this range. Note: Oreodonts are found in the fossil record as recently as 5 million years ago but the latest Oreodont in the Badlands was 26.8 million years ago (mya).

  • Brontotheres and alligators - mark off 33 to 38 million years ago. Place the students' dioramas in this range. The oreodonts will overlap with the brontotheres and alligators.

  • Mosasaur - mark off 69 million years ago to 74.7 million years ago (round up to 75 for younger students).  Place students' dioramas in the age. Mosasaurs differ from the other animals studied in this unit in that they are an aquatic animal. Their fossils show adaptations to living in water. When mosasaurs lived, the Badlands was covered in ocean. Essentially, the Gulf of Mexico extended all the way up through the US into Canada. 

Apply 

• Have students apply their knowledge about the fossils' habitats to describe the sequence of fossils found in the Badlands as represented on the timeline. An example of the sequence description: The Western Interior Seaway created a marine environment where mosasaurs lived. The Western Interior Seaway disappeared and with it the mosasaurs. The Earth changed slowly. Eventually what used to be covered in ocean became a warm, lush forest where alligators, brontotheres and oreodonts lived. The climate began to slowly cool. As it cooled, the brontotheres went extinct and alligators died out locally although we can still find alligators in warm, lush forests today. Oreodonts were able to adapt to the changes in climate and continued living in the Badlands area but eventually they died out as well, most likely due to the Ice Age. 

• Have students engage with the OSEU Integration resources.

• Watch Prehistoric Road Trip: Meet the Mammals. Have students study the other mammals.

Assess and Reflect 

• Possible assessment questions:

  • Which is closest in time to us? The Mosasaur or Oreodont? (Oreodont)

  • You are hiking in the Badlands and find a very sharp fossil tooth. Do you think it belongs to a Brontothere or Alligator? Why? (Carnivores - Alligators - had sharp teeth for grabbing and killing prey while Brontotheres had teeth for grabbing and grinding vegetation.

  • Explain why the Brontotheres may have gone extinct but the Alligators didn't. (The plant community changed and the Brontotheres could not adapt to the new vegetations. The Alligators as meat eaters could still find prey even with different vegetation).

  • What changes happened in the climate between the earliest Brontothere and the latest Oreodont? The climate changed from warm and humid to cool and dry.

OSEU Integration

• Watch Prehistoric Road Trip: Examining the History of Fossil Collection from Native American Lands. Discuss the practice of collecting fossils and ownership of fossils. 

• Read Lakota Connections to Fossils, a summary of two Lakota stories involving fossils. 

Additional Resources

Resources from Badlands National Park

• 3D Fossils (BADL) Dimensional Fossils of Badlands National Park and South Dakota to view. Some available for download to print. Includes a list of websites with 3D models.3D (Excel sheet). Created by Ed Welsh, Education Specialist, Badlands National Park, February 2023. Public domain resource.

• Fauna Confirmed from Badlands Area in South Dakota (Non-mammalian) A list of the non-mammalian fossils found in Badlands National Park and surrounding areas. Created by Ed Welsh, Education Specialist, Badlands National Park, February 2023. Public domain resource.

• Fauna Confirmed from Badlands Area in South Dakota (Mammalian). A list of the mammalian fossils found in Badlands National Park and surrounding areas. Created by Ed Welsh, Education Specialist, Badlands National Park, February 2023. Public domain resource.

• Other Badlands National Park education resources