Earth Science Week Classroom Activities

Adaptations of Cave Critters

Activity Source:

Adapted with permission by National Park Service

Caves with the National Natural Landmark (NNL) designation are some of the most fascinating of the thousands of caves around the world, and each one is unique. Caves’ special features are the product of various types of rock, their geologic setting, local climate, and time. This diversity in cave environments provides unique habitats for many different species of plants, animals, and other types of organisms. Each organism has developed specialized adaptations to survive in these cave environments.

Cave-dwelling animals, called Troglofauna, thrive in dark environments. Troglofauna are further subdivided into more categories according to how the cave is used. Troglobites (troglo : cave, and bios : life) live their whole lives in caves, while others spend just a part of their lives in caves and are called Trogloxene (troglo : cave, and xenos : guest).

Full-time cave dwellers have adaptations to their environments, such as being eyeless, blind, or colorless. Cave salamanders in NNL Marvel Cave in Missouri and cave crayfish in NNL Shelta Cave in Alabama are white and blind. These troglobites live in darkness. NNL Onondaga Cave in Missouri is home to grotto salamanders. When young, their brown and yellow flecked coloring blends with the environment near cave entrances where they live. As adults, they move deep into caves, becoming blind and losing most of their coloration. Mexican free- tailed bats sleep in caves like NNL Devil’s Sinkhole Natural Area in Texas all day, emerging at dusk. Hunting in darkness, they use echolocation to find insect prey.

In this activity, students will explore their creativity and critical thinking while they imagine a cave environment and create an organism that lives in their cave. Their cave will be one of the types mentioned in the preceding pages, but their organisms will be of their own imagination.

Materials

• 2 sheets of blank paper
• Coloring utensils
• Computer with internet connection

Procedure

1. On one sheet of paper, create a cave setting. Before drawing, discuss geologic and environmental conditions of cave environments:

• How do different types of caves — solution, lava, sea, talus— form?
• What types of geologic features are found in each type of cave?
• What is the climate of your cave— hot or cold, wet or dry?
• How big is the cave?
• How much water is in the cave? Does it flow? Or is it still?
• How dark does the cave get?
• Is the entrance large or small? A hole in the ground or on the side of a cliff or hill?

2. On another sheet of paper, create an organism that is adapted to live in that cave. Before drawing, discuss:

• Is the organism an animal, plant, or bacteria? If an animal, is it a reptile, fish, mammal, or other?
• How big is it?
• How does it get its nutrients?
• How does it defend itself?
• How does it move?
• How does it behave?

3. Describe to the members of the group or your class why your organism is well-suited to live in your cave. Consider:

• What would happen to your caves or organisms if there was an environmental change? What if the temperature rose due to climate change? What if there were an earthquake, flood, or drought?
• How does learning about the interesting traits and adaptations of cave critters inspire you?
• What adaptations and traits do people have to allow them to survive in our environment?

Compare your cave and organism with those of other students.

Discuss:

• How would your organism survive— or not — in your classmate’s cave? What elements of that cave would be helpful or harmful to your organism?
• How would your organism and your classmate’s organism interact with each other? Would they likely eat each other, fight, or get along? Are they competitors?

NGSS Connections

Crosscutting Concepts

- Cause and effect

- Structure and function

Science and Engineering Practices

- Asking questions and defining problems

- Engaging in argument from evidence

- Developing and using models

Disciplinary Core Ideas

- Life Science:
• Interdependent relationships in ecosystems
• Adaptation
• Natural Selection
- Earth and Space Science