Exploring Matthaei s Ecosystems

Transcription

1 Name: Exploring Matthaei s Ecosystems As you walk on the trails, look for evidence of each of the following components of an ecosystem. Draw and describe what you observed and where you found it. Component Organism Where did you find it? Producer Primary Secondary Decomposer

2 Teacher Guide Exploring Matthaei s Ecosystems As you walk on the trails, look for evidence of each of the following components of an ecosystem. Draw and describe what you observed and where you found it. Component Organism Where did you find it? Producer Primary Secondary Decomposer Producers are organisms that make their own food. Most producers are plants. Through the process of photosynthesis, they use energy from sunlight to make glucose (sugars) from carbon dioxide and water. Plants also require nutrients like nitrogen and phosphorous, which they usually absorb from the soil. The plant can then use these sugars to make parts including leaves, roots, stems, and reproductive organs. At Matthaei, producers include many terrestrial and aquatic plants. Students should find and describe a producer that is interesting to them, and note its location. s are organisms that cannot make their own food. Because they can t make food, they get their energy from eating other organisms. Primary consumers are organisms that eat producers. This means they are herbivores or omnivores. They use the energy they get from eating plants for movement, staying warm, and building and maintaining their own tissues. Primary consumers at Matthaei include insects, deer, and small rodents, like voles and mice. Many birds also consume seeds. Encourage students to think about what specific plants these consumers might eat, and what secondary consumers might eat them. Like primary consumers, secondary consumers cannot make their own food. They get their energy from eating primary consumers. Secondary consumers can be carnivores or omnivores. At each level, some energy is lost as heat as organisms use energy for processes like building and repairing tissues, digesting food, and maintaining body temperature. This means that there is less energy available to secondary consumers than there is to primary consumers, and consequently, their populations are smaller. Secondary consumers commonly found at Matthaei include the Massasauga rattlesnake, turtles, and herons. Decomposers are usually small organisms, like bacteria and fungi. They eat dead organisms or waste from living organisms. They break these complex substances down into their nutrient components. Decomposers are the final consumers of an ecosystem, and they return material that was once living back to the environment, where it can be absorbed by producers (plants) again. At Matthaei, students might notice fungi growing on a log or sprouting from the ground. However, many decomposers are difficult to see with the naked eye. Encourage students to look for evidence of the presence of decomposers, including rotting wood or other decomposing organisms.

3 Name: Plant-Animal Interactions In this activity, you will explore the conservatory and the trails at Matthaei to find evidence of different types of relationships between plants and animals. Read about each different type of interaction on the left side of the chart. On the right side, use the questions provided to guide your observations, notes, and sketches. Conservatory Mutualism: Ant Plants Plants provide habitat for many animals. As you walk through the tropical house, look for ant plants. Many of them have hollow structures called domatia, which provide a secure place for ants to build their nest. The plants get something out of this relationship too: the waste the ants leave behind is high in nutrients, which the plant can absorb. In some cases, the ants also defend the plant and disperse its seeds. Predation: Insectivorous Plants The bog in the temperate house contains several species of insectivorous plants, which trap and digest insects in order to obtain essential nutrients. One of those species is the pitcher plant. It has specialized leaves that are folded to contain a pitcher of water with digestive enzymes. The inside of the pitcher has downwardpointing hairs that prevent the insect from escaping before it is digested. Predation: Defense As you walk around the arid house, try to find structures that might help plants defend themselves against herbivory. Many desert plants store water in their stems and leaves, so animals seek them out for water in addition to nutrition. Cactuses have spines to protect their fleshy stems, while living stone plants have leaves that camouflage, or blend in, with the stones and sand around them. Choose your favorite ant plant in the tropical house and draw the domatia here. Examine another species of insectivorous plant in the bog. How do you think it traps and digests insects? Sketch examples of structures for defense or camouflage here.

4 Trails Parasitism: Galls As you walk along the trails, look for a round swelling in the stem of a goldenrod plant. This is where a goldenrod gall fly has laid an egg inside the stem. As the larva develops, its secretions cause the ball-shaped swelling in the stem to form. The larva will change into a pupa, and stay in the gall all winter. In the spring, it will emerge from the gall as a fly, and may eventually lay its own eggs in another stem. Predation: Herbivory Herbivory is the consumption of plants by animals. Animals that eat plants are called herbivores. As you walk along the trails, look for signs that herbivores are present at Matthaei. Look carefully at leaves for different types of bite marks. Herbivores have different mouths and mouthparts, which damage leaves differently. The type of leaf damage you find is a clue about what types of herbivores live here. Mutualism: Pollination 80% of flowering plants require an animal pollinator in order to reproduce, or make new plants. These plants generally have brightly colored or strongly scented flowers to attract pollinators, who visit flowers in order to collect nectar and pollen as food. As they drink nectar, they unintentionally move pollen from the flower s stamens to the pistil. Once the pollen is on the pistil, the flower can use it to make seeds. Draw a goldenrod gall below. Indicate whether or not the fly has emerged. Draw the evidence of herbivory you found here. Make a prediction about what animals caused the marks you drew. Choose a flower from the display gardens or trails to observe. Note any pollinators that visit the flower here. Choose one plant-animal interaction that is particularly interesting to you. Try to think of a question you have about that relationship. How could you investigate that question further?

5 Teacher Guide Plant-Animal Interactions In this activity, you will explore the conservatory and the trails at Matthaei to find evidence of different types of relationships between plants and animals. Read about each different type of interaction on the left side of the chart. On the right side, use the questions provided to guide your observations, notes, and sketches. Conservatory Mutualism: Ant Plants Plants provide habitat for many animals. As you walk through the tropical house, look for ant plants. Many of them have hollow structures called domatia, which provide a secure place for ants to build their nest. The plants get something out of this relationship too: the waste the ants leave behind is high in nutrients, which the plant can absorb. In some cases, the ants also defend the plant and disperse its seeds. Predation: Insectivorous Plants The bog in the temperate house contains several species of insectivorous plants, which trap and digest insects in order to obtain essential nutrients. One of those species is the pitcher plant. It has specialized leaves that are folded to contain a pitcher of water with digestive enzymes. The inside of the pitcher has downwardpointing hairs that prevent the insect from escaping before it is digested. Predation: Defense As you walk around the arid house, try to find structures that might help plants defend themselves against herbivory. Many desert plants store water in their stems and leaves, so animals seek them out for water in addition to nutrition. Cactuses have spines to protect their fleshy stems, while living stone plants have leaves that camouflage, or blend in, with the stones and sand around them. Choose your favorite ant plant in the tropical house and draw the domatia here. Ant plants are located at several different places throughout the tropical house. Some are in the branches of trees, while others are displayed on the walls by the two curved paths in the tropical house. Ant plants can be identified by their domatia, which are the hollow structures where the ants build their nests. Students should be encouraged to find several examples of ant plants before they choose to draw one. Examine another species of insectivorous plant in the bog. How do you think it traps and digests insects? Some students will likely recognize the Venus flytrap in the bog. These plants have specialized leaves with traps at the tip. They are triggered when an insect makes contact with tiny hairs on the inside of the trap twice within 30 seconds. Sundews are another insectivorous plant in the bog exhibit. Their leaves are covered with a sticky substance that traps insects. The plant then secretes enzymes to digest them. Sketch examples of structures for defense or camouflage here. Cactus spines are a modified leaf structure, and students will find a variety of examples in the arid house. Note that very small spines can still cause considerable damage. The rabbit ears cactus has small barbed spines that detach even if touched very lightly. The display case at the front of the arid house contains dozens of living stone plants. Each of these succulents has two or more leaves that store water. Camouflage protects them from predation.

6 Teacher Guide Trails Parasitism: Galls As you walk along the trails, look for a round swelling in the stem of a goldenrod plant. This is where a goldenrod gall fly has laid an egg inside the stem. As the larva develops, its secretions cause the ball-shaped swelling in the stem to form. The larva will change into a pupa, and stay in the gall all winter. In the spring, it will emerge from the gall as a fly, and may eventually lay its own eggs in another stem. Predation: Herbivory Herbivory is the consumption of plants by animals. Animals that eat plants are called herbivores. As you walk along the trails, look for signs that herbivores are present at Matthaei. Look carefully at leaves for different types of bite marks. Herbivores have different mouths and mouthparts, which damage leaves differently. The type of leaf damage you find is a clue about what types of herbivores live here. Mutualism: Pollination 80% of flowering plants require an animal pollinator in order to reproduce, or make new plants. These plants generally have brightly colored or strongly scented flowers to attract pollinators, who visit flowers in order to collect nectar and pollen as food. As they drink nectar, they unintentionally move pollen from the flower s stamens to the pistil. Once the pollen is on the pistil, the flower can use it to make seeds. Draw a goldenrod gall below. Indicate whether or not the fly has emerged. Goldenrod galls (round, ball-shaped swellings in goldenrod stems) can be found along the Sue Reichert and Sam Graham Trails throughout the year, in living and dead stems. Students should look for holes in the gall--small holes indicate that the fly has emerged while large ones suggest it was eaten by a bird. Draw the evidence of herbivory you found here. Make a prediction about what animals caused the marks you drew. If students observe leaves carefully, they will be able to find damage caused by many different types of insects as well as deer. Encourage students to draw the exact shape of bite marks on leaves, as the shapes provide clues about what animals are present. Standing dead trunks can also be examined for insect damage, which often take the form of trails in the bark. Students may also note animals that eat seeds. Choose a flower from the display gardens or trails to observe. Note any pollinators that visit the flower here. Students should think about which flowers are attractive to pollinators before they choose one to observe. Brightly colored flowers in clusters are more likely to be visited by pollinators. Students should observe the flower for several minutes and write about any pollinators that visit. Encourage students to examine the flower carefully to locate its reproductive structures and pollen. Choose one plant-animal interaction that is particularly interesting to you. Try to think of a question you have about that relationship. How could you investigate that question further?