© Brian Gratwicke
Visit our Rainforest exhibit to observe adaptations that make frogs well suited to survive humid environments. This museum worksheet comes with question prompts for chaperones to help engage students in scientific discourse.
Through this scavenger hunt, students will:
- learn about adaptations that make frogs well suited to survive humid environments.
- observe examples of frogs in the Rainforest Exhibit.
- Troubled Tree Frogs Scavenger Hunt (one copy per group)
- Troubled Tree Frogs Chaperone Guide (one for each chaperone)
Note: The hunt is purposefully designed to be facilitated by chaperones rather than completed by students with pencils. Why? On occasion, visitors have accidentally dropped personal items into the open-top aquarium at the ground level of the Rainforest, only to be swallowed by our catfish! For the safety of the live animals on exhibit, we ask that personal belongings be stowed away as you wander up the ramp.
adaptation: a structure or behavior that increases an organism’s chance of surviving and reproducing in a particular environment
evaporate: to change from liquid water to water vapor
Many of the potential threats faced by tree frogs arise from their characteristic skin: a thin, scale-less, moist layer that easily exchanges water and gases with the environment. Sometimes this permeable skin is an advantage. For example, many frogs have a ‘seat patch’ on their rear end, a special section of tissue that absorbs water particularly well. So instead of drinking through its mouth, a frog can stick its bum in a pool of water to quench its thirst!
Frog skin also performs an important role in frog respiration. Because the lungs of an adult frog are hollow sacs, surface area is minimal and the exchange of gases is less efficient than in mammals. Frogs don’t inhale and exhale regularly like humans, dogs, and cats, but rather take in large gulps on occasion. The majority of a frog’s gas exchange is instead performed through its moist skin. Oxygen from the air dissolves in a layer of mucus covering the body, diffuses through the skin into the bloodstream, and travels to the frog’s cells. In summary, a frog both drinks and breathes through its skin!
The large surface area of the skin relative to a tree frog’s volume is thus helpful for providing the body with plenty of water and oxygen. However, this skin can become a handicap when the environment is not ideal. For example, acid rain, water pollution, natural toxins, and fungus, can injure a frog’s sensitive skin, or easily pass into the body. Water loss due to evaporation from the skin is also a great physiological danger. Variables such as low humidity, heat, and high wind increase the rate of water evaporation, leaving a frog vulnerable to dehydration. Without water covering its body, the frog will have a tough time capturing enough oxygen for its cells!
- 3b. Students know that in any particular environment, some kinds of plants and animals survive well, some survive less well, and some cannot survive at all.
- 2a. Students know many multicellular organisms have specialized structures to support the transport of materials.
- 3b. Students know when liquid water evaporates, it turns into water vapor in the air and can reappear as a liquid when cooled or as a solid if cooled below the freezing point of water.