This lists the logos of programs or partners of NG Education which have provided or contributed the content on this page.
Program
1. Students use perception sketches to illustrate their observations as they listen to the National Geographic video “Ultimate Enemies.”
Tell students that they are going to make perception sketches. Instruct students to close their eyes and listen to what they hear in the classroom. Have students listen carefully for one minute. Afterward, tell them to draw symbols and shapes (not words) in their notebooks to describe what they heard. Have students share their observations aloud. Discuss similarities and differences in what they heard. Next, explain to students that they will make another perception sketch, but this time they will be listening to the National Geographic video “Ultimate Enemies.” Encourage students to listen for and sketch multiple layers of what they hear. After listening to the video, write the following questions on the board and have students share their observations aloud. Ask:
- What symbols or shapes did you sketch? What do they represent?
- What is the video about?
- Where did the video take place?
- What types of animals did you hear?
- What type of ecological community or ecosystem do you think is represented in the video?
Elicit from students that the video is about a community of organisms that includes birds, lions, hyenas, and elephants. Explain that this particular community lives in Botswana, Africa.
2. Students use perception sketches to illustrate their observations as they watch the same video.
After listening to the video and discussing their perception sketches, students may not know the ecosystem type yet. Without telling students the ecosystem type, play the video again, but this time allow them to watch and listen as they record their observations and responses to the questions in their notebook. Afterward, discuss students’ observations. Discuss the questions again, noting whether or not students’ answers have changed or become more refined. Elicit from students that the video is about organisms living in an African savanna ecosystem. Explain that a savanna is a type of tropical grassland with scattered trees.
3. Build background about ecosystem ecology: environment and communities.
Draw a two-column chart on the board and write the following heads: Terms and Notes. Then write the following terms in the left-hand column: ecosystem, environment, organism/community, food chain, and food web. Provide students with the Two-Column Chart worksheet or have them draw the chart and write the terms in their notebooks. In the right-hand column next to the term ecosystem, have students record the ecosystem type (savanna) shown in the video. Next, have them write a description of the savanna’s environment next to the term environment. Ask: What are the nonliving components that characterize the environment of the ecosystem? Elicit from students that environments are characterized by soil, water, temperature, sunlight, wind, and rainfall. Explain that the African savanna is also called tropical grassland. It has warm temperatures year-round and rainfall is seasonal, being highest in the summer. The savanna is characterized by grasses and small or dispersed trees that do not form a closed canopy, allowing sufficient sunlight to reach the ground. Tell students that a group of organisms interacting in a specific region under similar environmental conditions is called a community. Display the African Savanna Ecosystem illustration. Have students use the illustration and their video observations to record several organisms that make up the African savanna ecosystem.
4. Identify African savanna feeding relationships: food chains and food webs.
Ask: What is a food chain? (A food chain is a group of organisms linked in order of the food they eat, from producers to consumers, prey to predators, and scavengers to decomposers.) Using the two-column chart, have students identify one or more food chains using the organisms they listed in Step 3. Elicit responses that include organisms from different feeding levels: producer, primary consumer (herbivore), secondary consumer (carnivore), omnivore, decomposer, insectivores, scavengers, and detritivores. Use the African Savanna Illustration Key to write at least two sample food chains on the board and label their feeding levels. Ask: Why do food chains have arrows between organisms and not just straight lines? Elicit from students that arrows represent the flow of energy and matter between feeding levels. Be sure to point out the role of decomposers, omnivores, and other feeding groups with which students may be less familiar. Ask: What is a food web? How is a food web related to a food chain? Elicit from students that food chains show only one path of food and energy through an ecosystem. In most ecosystems, organisms can get food and energy from more than one source, and may have more than one predator. Healthy, well-balanced ecosystems are made up of multiple, interacting food chains, called food webs. As a class, have students practice combining two of the savanna food chains to create a food web.
5. Assign students roles in the African savanna ecosystem.
Tell students that they will build their own African savanna community web based on the organisms and environmental factors they discussed and observed throughout the activity. Have students work individually or in pairs and assign them one of the organisms or environmental factors listed in the African Savanna Background Information handout. Tell them to use string and index cards to create an ecosystem role card that includes what they represent (organism or environmental factor), and their relationship to other components of the savanna ecosystem. Students should write the name of their organism/factor on one side of the card, and then list types of interactions on the other side. Organism interactions can include feeding relationships and resources the organisms compete for or share with other organisms. Tell students they should be able to state, “I am the (what they represent) and I am connected to (relationship to other components of the ecosystem) because…”
6. Have students create a community web for the African savanna ecosystem.
Have students stand in a large circle with their ecosystem role cards visible. One at a time, have students read aloud from their card, “I am the…and I am connected to…because…” and toss the ball of string to the environmental factor or organism (student) they are connected to. Discuss the relationships and continue building the community web until all roles are part of the web. Next, have one student let go of the string and discuss what would happen if that factor or organism were no longer part of the community web. Then, have another connected student let go of the string. With an emphasis on the African savanna ecosystem, discuss how all of the strings are essential in keeping the web together. Discuss how humans interact with the African savanna community. Ask: What is the role of humans in the ecosystem? (Humans are omnivores and top-level consumers. They use ecosystem resources and alter the environment so they often compete with other organisms for food and space.) Ask: How do humans and big cats interact? What about the cattle? Elicit from students that humans and big cats have a similar role in terms of feeding relationships. They are both top carnivores and help balance the ecosystem by consuming herbivores. Humans and lions also come into conflict because people can kill lions and destroy or use the lions’ habitat for cattle and agriculture. Big cats can, in turn, kill humans and their cattle and become competitors for food and space.
Informal Assessment
Review students' two-column charts and observe students as they create and discuss their African savanna community web.
Extending the Learning
Have students create in their notebooks a complete food web using the organisms included in the African savanna ecosystem illustration.
Subjects & Disciplines
- Biology
- Geography
Learning Objectives
Students will:
- identify the environment and organisms of the African savanna ecosystem
- create a community web for the African savanna ecosystem
- identify and describe feeding relationships that comprise the African savanna food web
- discuss how humans interact with the environment and organisms of the African savanna community
Teaching Approach
- Learning-for-use
Teaching Methods
- Discussions
- Guided listening
- Information organization
- Multimedia instruction
Skills Summary
This activity targets the following skills:
- 21st Century Themes
-
Critical Thinking Skills
- Analyzing
- Creating
- Understanding
- Geographic Skills
Connections to National Standards, Principles, and Practices
National Council for Social Studies Curriculum Standards
- Theme 3: People, Places, and Environments
National Geography Standards
- Standard 4: The physical and human characteristics of places
- Standard 8: The characteristics and spatial distribution of ecosystems and biomes on Earth's surface
National Science Education Standards
- (5-8) Standard C-4: Populations and ecosystems
- (5-8) Standard C-5: Diversity and adaptations of organisms
- (5-8) Standard F-2: Populations, resources, and environments
What You’ll Need
Materials You Provide
- Ball of string
- Colored pencils
- Index cards
- Pencils
Required Technology
- Internet Access: Required
- Tech Setup: 1 computer per classroom, Projector, Speakers
- Plug-Ins: Flash
Physical Space
- Classroom
Grouping
- Large-group instruction
Other Notes
Use the recommended resources in "For Further Exploration" to review background information and vocabulary relevant to the ecology and feeding relationships of the tropical savanna ecosystem.
Background Information
The African savanna ecosystem is a tropical grassland with warm temperatures year round and seasonal rainfall. The savanna is characterized by grasses and small or dispersed trees, along with a diverse community of organisms that interact to form a complex food web. Carnivores (lions, hyenas, leopards) feed on herbivores (impalas, warthogs, cattle) that consume producers (grasses, plant matter). Scavengers (hyenas, vultures) and decomposers/detritivores (bacteria, fungi, termites) break down organic matter, making it available to producers and completing the food cycle (web). Humans are part of the savanna community and often compete with other organisms for food and space.
Prior Knowledge
- food chains and food webs
Recommended Prior Activities
- None
Vocabulary
National Geographic Society program that supports on-the-ground conservation projects, education, economic incentive efforts, and a global public-awareness campaign to protect big cats and their habitats.
group of organisms or a social group interacting in a specific region under similar environmental conditions.
organism on the food chain that depends on autotrophs (producers) or other consumers for food, nutrition, and energy.
organism that breaks down dead organic material; also sometimes referred to as detritivores
organism that consumes dead plant material.
conditions that surround and influence an organism or community.
group of organisms linked in order of the food they eat, from producers to consumers, and from prey, predators, scavengers, and decomposers.
organism that mostly eats insects.
living or once-living thing.
animal that hunts other animals for food.
organism on the food chain that can produce its own energy and nutrients. Also called an autotroph.
type of tropical grassland with scattered trees.
Images
Websites
Tips & Modifications
Tip Teacher Tip
Refer to African Savanna Background Information and Big Cats Background Information for additional content information.
-
Limiting Factors
A limiting factor is anything that constrains a population's size and slows or stops it from growing. Some examples of limiting factors are biotic, like food, mates, and competition with other organisms for resources. Others are abiotic, like space, temperature, altitude, and amount of sunlight available in an environment. Limiting factors are usually expressed as a lack of a particular resource. For example, if there are not enough prey animals in a forest to feed a large population of predators, then food becomes a limiting factor. Likewise, if there is not enough space in a pond for a large number of fish, then space becomes a limiting factor. There can be many different limiting factors at work in a single habitat, and the same limiting factors can affect the populations of both plant and animal species. Ultimately, limiting factors determine a habitat's carrying capacity, which is the maximum size of the population it can support. Teach your students about limiting factors with this curated collection of resources.
-
Energy Flow Through an Ecosystem
Trophic levels provide a structure for understanding food chains and how energy flows through an ecosystem. At the base of the pyramid are the producers, who use photosynthesis or chemosynthesis to make their own food. Herbivores or primary consumers, make up the second level. Secondary and tertiary consumers, omnivores and carnivores, follow in the subsequent sections of the pyramid. At each step up the food chain, only 10 percent of the energy is passed on to the next level, while approximately 90 percent of the energy is lost as heat. Teach your students how energy is transferred through an ecosystem with these resources.
-
Food Chains and Webs
A food chain outlines who eats whom. A food web is all of the food chains in an ecosystem. Each organism in an ecosystem occupies a specific trophic level or position in the food chain or web. Producers, who make their own food using photosynthesis or chemosynthesis, make up the bottom of the trophic pyramid. Primary consumers, mostly herbivores, exist at the next level, and secondary and tertiary consumers, omnivores and carnivores, follow. At the top of the system are the apex predators: animals who have no predators other than humans. Help your class explore food chains and webs with these resources.
-
Biomes
A biome is an area classified according to the species that live in that location. Temperature range, soil type, and the amount of light and water are unique to a particular place and form the niches for specific species allowing scientists to define the biome. However, scientists disagree on how many biomes exist. Some count six (forest, grassland, freshwater, marine, desert, and tundra), others eight (separating two types of forests and adding tropical savannah), and still others are more specific and count as many as 11 biomes. Use these resources to teach middle school students about biomes around the world.
-
Cell Functions
A cell is one of the building blocks of life. Cells are membrane-bound groups of organelles that work together to allow it to function. Some of the major organelles include the nucleus, mitochondria, lysosomes, the endoplasmic reticulum, and the Golgi apparatus. Plant cells also include chloroplasts, which are responsible for photosynthesis. Use these classroom resources to examine how cells function with your students.
-
Big Cats
Lions, tigers, and other big cats occupy a special place in the human imagination as beautiful, graceful, and dangerous. But these top predators have more to fear from humans than humans do from them. Many of these once-prolific species are endangered from poaching, territory loss, and climate change. Learn about these vital creatures through the resources in this collection.
-
Habitats and Microhabitats
A habitat is an environment where an organism lives throughout the year or for shorter periods of time to find a mate. The habitat contains all an animal needs to survive such as food and shelter. A microhabitat is a small area which differs somehow from the surrounding habitat. Its unique conditions may be home to unique species that may not be found in the larger region. Unfortunately, some habitats are threatened by pollution, extreme weather, or deforestation. This puts many of the species that live there in danger and is causing many populations to decline. Explore different types of habitats and microhabitats with this curated collection of classroom resources.
-
Serengeti
Among Africa's many savanna regions, the Serengeti (or Serengeti Plains) is the most well-known. The Serengeti is a vast, undulating plain that stretches 30,000 square kilometers (11,583 square miles) from Kenya's Maasai-Mara game reserve to Tanzania's Serengeti National Park. The Serengeti is home to one of the continent's highest concentrations of large mammal species, including lions, hyenas, zebras, giraffes, and elephants. Each year, more than one million wildebeest travel in a circular migration, following seasonal rains, across the Serengeti Plains. Their grazing and trampling of grass allows new grasses to grow, while their waste helps fertilize the soil.
-
Terrestrial Ecosystem
A terrestrial ecosystem is a land-based community of organisms and the interactions of biotic and abiotic components in a given area. Examples of terrestrial ecosystems include the tundra, taigas, temperate deciduous forests, tropical rainforests, grasslands, and deserts. The type of terrestrial ecosystem found in a particular place is dependent on the temperature range, the average amount of precipitation received, the soil type, and amount of light it receives. Use these resources to spark student curiosity in terrestrial ecosystems and discover how different abiotic and biotic factors determine the plants and animals found in a particular place.
-
Web
Worksheet. Graphic organizers are useful tools for building knowledge and organizing information. You can use a web to identify relationships between related things.
-
Food Web Fun
Students participate in a simulation of a Shark Bay food web to see the relationships between members of that ecosystem.
-
No Species Lives in Isolation
Students watch a video that explores biodiversity in Patagonia. Based on this example, students then identify major groups of organisms in Indonesian forests. Using a model food web from a backyard ecosystem, the class builds a food web that shows the relationships between the Sumatran rhino and other species in its ecosystem.
-
Limiting Factors
A limiting factor is anything that constrains a population's size and slows or stops it from growing. Some examples of limiting factors are biotic, like food, mates, and competition with other organisms for resources. Others are abiotic, like space, temperature, altitude, and amount of sunlight available in an environment. Limiting factors are usually expressed as a lack of a particular resource. For example, if there are not enough prey animals in a forest to feed a large population of predators, then food becomes a limiting factor. Likewise, if there is not enough space in a pond for a large number of fish, then space becomes a limiting factor. There can be many different limiting factors at work in a single habitat, and the same limiting factors can affect the populations of both plant and animal species. Ultimately, limiting factors determine a habitat's carrying capacity, which is the maximum size of the population it can support. Teach your students about limiting factors with this curated collection of resources.
-
Energy Flow Through an Ecosystem
Trophic levels provide a structure for understanding food chains and how energy flows through an ecosystem. At the base of the pyramid are the producers, who use photosynthesis or chemosynthesis to make their own food. Herbivores or primary consumers, make up the second level. Secondary and tertiary consumers, omnivores and carnivores, follow in the subsequent sections of the pyramid. At each step up the food chain, only 10 percent of the energy is passed on to the next level, while approximately 90 percent of the energy is lost as heat. Teach your students how energy is transferred through an ecosystem with these resources.
-
Food Chains and Webs
A food chain outlines who eats whom. A food web is all of the food chains in an ecosystem. Each organism in an ecosystem occupies a specific trophic level or position in the food chain or web. Producers, who make their own food using photosynthesis or chemosynthesis, make up the bottom of the trophic pyramid. Primary consumers, mostly herbivores, exist at the next level, and secondary and tertiary consumers, omnivores and carnivores, follow. At the top of the system are the apex predators: animals who have no predators other than humans. Help your class explore food chains and webs with these resources.
-
Biomes
A biome is an area classified according to the species that live in that location. Temperature range, soil type, and the amount of light and water are unique to a particular place and form the niches for specific species allowing scientists to define the biome. However, scientists disagree on how many biomes exist. Some count six (forest, grassland, freshwater, marine, desert, and tundra), others eight (separating two types of forests and adding tropical savannah), and still others are more specific and count as many as 11 biomes. Use these resources to teach middle school students about biomes around the world.
-
Cell Functions
A cell is one of the building blocks of life. Cells are membrane-bound groups of organelles that work together to allow it to function. Some of the major organelles include the nucleus, mitochondria, lysosomes, the endoplasmic reticulum, and the Golgi apparatus. Plant cells also include chloroplasts, which are responsible for photosynthesis. Use these classroom resources to examine how cells function with your students.
-
Big Cats
Lions, tigers, and other big cats occupy a special place in the human imagination as beautiful, graceful, and dangerous. But these top predators have more to fear from humans than humans do from them. Many of these once-prolific species are endangered from poaching, territory loss, and climate change. Learn about these vital creatures through the resources in this collection.
-
Habitats and Microhabitats
A habitat is an environment where an organism lives throughout the year or for shorter periods of time to find a mate. The habitat contains all an animal needs to survive such as food and shelter. A microhabitat is a small area which differs somehow from the surrounding habitat. Its unique conditions may be home to unique species that may not be found in the larger region. Unfortunately, some habitats are threatened by pollution, extreme weather, or deforestation. This puts many of the species that live there in danger and is causing many populations to decline. Explore different types of habitats and microhabitats with this curated collection of classroom resources.
-
Serengeti
Among Africa's many savanna regions, the Serengeti (or Serengeti Plains) is the most well-known. The Serengeti is a vast, undulating plain that stretches 30,000 square kilometers (11,583 square miles) from Kenya's Maasai-Mara game reserve to Tanzania's Serengeti National Park. The Serengeti is home to one of the continent's highest concentrations of large mammal species, including lions, hyenas, zebras, giraffes, and elephants. Each year, more than one million wildebeest travel in a circular migration, following seasonal rains, across the Serengeti Plains. Their grazing and trampling of grass allows new grasses to grow, while their waste helps fertilize the soil.
-
Terrestrial Ecosystem
A terrestrial ecosystem is a land-based community of organisms and the interactions of biotic and abiotic components in a given area. Examples of terrestrial ecosystems include the tundra, taigas, temperate deciduous forests, tropical rainforests, grasslands, and deserts. The type of terrestrial ecosystem found in a particular place is dependent on the temperature range, the average amount of precipitation received, the soil type, and amount of light it receives. Use these resources to spark student curiosity in terrestrial ecosystems and discover how different abiotic and biotic factors determine the plants and animals found in a particular place.
-
Web
Worksheet. Graphic organizers are useful tools for building knowledge and organizing information. You can use a web to identify relationships between related things.
-
Food Web Fun
Students participate in a simulation of a Shark Bay food web to see the relationships between members of that ecosystem.
-
No Species Lives in Isolation
Students watch a video that explores biodiversity in Patagonia. Based on this example, students then identify major groups of organisms in Indonesian forests. Using a model food web from a backyard ecosystem, the class builds a food web that shows the relationships between the Sumatran rhino and other species in its ecosystem.