FNR-573-W Adaptations for Aquatic Amphibians LESSON PLAN Understanding adaptations for aquatic amphibians can help humans learn more about healthy ecosystems. Overview 2 Teachers’ Notes 3 Procedure 10 Activities 11 AUTHORS Veronica K. Yager, Nicholas Burgmeier, and Rod N. Williams Department of Forestry and Natural Resources, Purdue University, West Lafayette, Indiana Adaptations for Aquatic Amphibians OVERVIEW LESSON PLAN ESTIMATED TIME REQUIRED MATERIALS 45-60 minutes • Hellbender photo or model; 1 per student, pre-test; 1 per student, post-test VOCABULARY Activity 1: Hellbender Adaptations • Adaptations • 1 large brown T-shirt • 1 paintbrush • Amphibian • 1 tube of black paint • Aquatic • 1 pair of swimming goggles (competition-style) • Behavioral adaptations • 6 wood clothespins (with spring) • Camouflage • 1 canoe paddle • Eastern Hellbender • 4 Hellbender photos: Figures 1-4 • Habitat • 1 Hellbender video of vacuum mouth • Indicator species • 1 container of pre-made slime • Permeable skin Activity 2: Herbie the Hellbender • Physical adaptations • 1 sponge (cut in the shape of a Hellbender) • 1 aquarium or clear plastic container UNIT OBJECTIVES • 10 scoops of gravel or small rocks Students will be able to: • 1 gallon of water 1. Explain how amphibian adaptations benefit survival • 1 cup of soil • 2 bottles of food coloring (at least two colors; best to use blue and 2. Describe the importance of Eastern Hellbender adaptations yellow) 3. Identify impacts that humans have on aquatic amphibians • 1 cup of assorted trash (e.g., paper / cardboard scraps, plastic lids) • 1 bottle of syrup (or food coloring for dark color) LESSON STANDARDS • 1 ruler or paint mixer Next Generation Science Standards Activity 3: Making Slime 3-LS4-3 • 2 16 oz. cans of corn starch 3-LS4-4 • 1 16 oz. bottle of liquid yellow dish soap MS-ESS3-3 • 1 32 oz. pitcher full of cold water English/Language Arts • 2 measuring cups SL.2.1 SL.3.1 SL.4.1 SL.5.1 SL.6.1 • 1 tablespoon for measuring water SL.2.2 SL.3.2 SL.4.2 SL.5.2 SL.2.3 SL.3.3 SL.4.3 SL.5.3 • 6 24 oz. bowls • 6 forks for mixing • 1 5-gallon bucket of water for washing hands • 2 or more towels to dry hands ACTIVITY ICONS Use these icons — located at the top of each lesson plan — to indicate the disciplines to which certain activities belong. These disciplines include: READING WRITING MATH SCIENCE STEM STEAM (science, technology, engineering, math) (science, technology, engineering, art, math) Cover photo credit: Rod Williams Find out more at purdue.edu/extension THE EDUCATION STORE edustore.purdue.edu It is the policy of the Purdue University Cooperative Extension Service that all persons have equal opportunity and access to its educational programs, services, activities, and facilities without regard to race, religion, color, sex, age, national origin or ancestry, marital status, parental status, sexual orientation, disability or status as a veteran. Purdue University is an Affirmative Action institution. This material may be available in alternative formats. March, 2019 2 Adaptations for Aquatic Amphibians TEACHERS’ NOTES LESSON PLAN ADAPTATIONS HELLBENDER ADAPTATIONS AND THE ENVIRONMENT Adaptations are inherited characteristics that enhance a species’ chances for survival and reproduction. Adaptations Hellbenders are the largest salamander in North America and allow a species to better use resources, obtain a mate, and can grow to be over two feet in length. These giant, aquatic gain protection from environmental stress. Every organism salamanders require clean rivers with cool, well-oxygenated in nature is adapted to live in its environment and all species water to breathe. They prefer areas of cobble and coarse gravel continuously adapt to the changing world. Adaptations are rather than sand, silt, and clay, and they need large rocks for important because if a species does not adapt to changes in cover to hide from predators and guard their young. The its environment, it becomes extinct (dies out). Hellbenders’ habitat (all of the food, water, shelter, and space to rear their young) is crucial to their survival. Hellbenders are Adaptations can be behavioral or physical. Behavioral considered habitat specialists because they require very adaptations occur when animals change the way they act in specific habitats and resources to survive and reproduce. order to stay alive and reproduce. An example of a behavioral Because of this, Hellbenders are extremely well-adapted to adaptation is migration (i.e., moving to find food or escape a fully aquatic lifestyle in flowing rivers under large boulders. the cold). Physical adaptations are changes in animals’ You can find evidence of this in their adaptations. bodies that help them survive and reproduce. An example of a physical adaptation is toe pads on a tree frog. This lesson 1. Camouflage: Hellbenders are mottled with dark brown focuses on adaptations for survival (continuing to live in spite or black spots, allowing them to blend in with gravel and of difficult circumstances). cobble rocks on the bottom of riverbeds (see Figures 1 and 2). Hellbenders hide under rocks in the river, and Adaptations are crucial in obtaining food. A predator captures camouflage is their main defense from predators (e.g., and feeds on other organisms. Prey animals are hunted or river otters and fish). seized as food. Many predators have developed an acute sense of smell, sight or other senses to help them find prey. 2. Skin folds: Among the Hellbender’s most unique However, prey species also have adaptations that deter characteristics are the extra folds of skin on its sides predators. For example, toads have glands behind their head that look like lasagna noodles (see Figure 3). These skin that release poison when attacked by a predator. The toad’s folds increase the Hellbender’s surface area and absorb poison causes the predator to salivate, which may allow the oxygen from the water through its permeable skin. toad to escape. Other species have adapted to blend in with 3. Smell: Smell helps the Hellbender detect hazards, their natural environments using camouflage (hiding or pheromones (chemicals released by other Hellbenders), disguising their presence). For example, a polar bear’s white and food. Hellbenders use their sense of smell to detect coat helps it blend in with the snow and ice so it can hunt seals. predators in the water (e.g., fish), find potential mates during All species undergo unique adaptations that help them the breeding season, and locate their prey (e.g., crayfish). survive in their environment. For this lesson, we are going 4. Vacuum mouth: The Hellbender’s mouth works like a to focus on amphibians. vacuum, and it swallows its prey by sucking food down. Amphibians are a vertebrate group that contains frogs, When the Hellbender opens its huge mouth, both water salamanders, and caecilians (suh-SEE-lee-uns; legless and the prey are sucked inside. The main prey item for amphibians). Most are adapted to live in and out of the water. Hellbenders is crayfish, but they will also eat aquatic Amphibians are frequently confused with reptiles, but reptiles insects and fish. have scaly skin. Amphibians usually have a smooth, slimy, and 5. Paddle tail: In order to escape from threats, Hellbenders permeable skin that allows water and air to pass through it. can propel themselves quickly through the water with Some amphibians are adapted to be fully aquatic and never their muscular, paddle-shaped tails. Hellbenders accelerate leave the water. Aquatic species live in the water for most or through the water by moving their tails back and forth, all of their lifespan and many have gills that allow them to and the tail’s shape is advantageous to help them move breathe in water. Three classic examples of aquatic adaptations as fast as they do (see Figure 4). are gills, permeable skin, and a paddle-like tail to help species 6. Slime: Hellbenders produce slime that serves as a predator swim. One example of a fully aquatic amphibian is the defense. The slime makes their skin slippery and has a Eastern Hellbender, and we will discuss some of their foul taste. Slime also protects Hellbenders from dangerous adaptations in detail. pathogens (i.e., disease-causing agents) that might be in the water. 3 Adaptations for Aquatic Amphibians TEACHERS’ NOTES LESSON PLAN IMPORTANCE OF CLEAN WATER FOR We can help protect the freshwater ecosystem by: AQUATIC AMPHIBIANS 1. Planting more trees near streams and rivers to Humans need clean freshwater to survive and so do aquatic prevent soil erosion and sedimentation. amphibians. Amphibians are adapted to aquatic systems, but Hellbender larvae (babies) have evolved to burrow into those adaptations may not be enough to protect them from spaces between rocks. When heavy loads of sediment all threats. erode into the river, the sediment fills in the areas of the rocks where larvae hide, making it easier for predators to Amphibians can be negatively affected by poor water quality eat them. during their aquatic stages because they can absorb harmful pollutants through their permeable skin. Poor water quality 2. Picking up trash and recycling to help keep litter from can lead to death or disease in amphibians that cannot reaching the river. tolerate pollution. Excess nutrients and sediment in runoff Wildlife can eat trash in the river that may cause them to from lawns, roads and agriculture can cause oxygen-reducing get sick and die. algae blooms and reduce available amphibian habitats. 3. Reducing impervious (hardened) surfaces by leaving Amphibians intolerant to pollution may serve as suitable sections of our property unpaved or unmown to indicator species. Indicator species are those that represent absorb water and help prevent runoff from picking the health of an ecosystem based on either their presence or up pollutants and reaching storm drains that flow absence.