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6.4.2

Organism

Interactions

Storyboard

Teacher instruction and hints are included within the speaker notes section

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6.4.2 Organism Interactions Matrix

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Teacher Overview: Episode 1

Phenomenon: Organisms interact with other living organisms in their environment.

Learning Goal: Students will construct an explanation for how animal interaction patterns can be found in different ecosystems.

CCCs:� Use the CCCs as a lens to help focus your lesson, questions, discussion, etc.

Patterns: Similar types of interactions (e.g., competition, mutualism) occur across different ecosystems.

Cause and effect: The presence of one species can cause changes in the behavior, survival, or reproduction of another species.

SEPs:� SEPs are actions that students complete to interact with the phenomena.

Obtaining, evaluating, and communicating information: Students watch and evaluate videos of organism interactions and record observations.

Engaging in arguments from evidence: Students use observations to make claims about whether similar interactions would occur in other ecosystems.

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Episode 1

Today’s Objective: I can construct an explanation about how patterns in animal interactions can be found in different ecosystems.

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Gather

National Geographic Crittercam

What other animals interact with the monk seal? Describe these interactions.

Gather

Students obtain information about patterns in the interaction between a monk seal and other organisms.

Teacher suggestions: Show students the following video link of a National Geographic crittercam on an Hawaiian monk seal. The monk seal preys upon and competes for fish and invertebrates on the seafloor 80 meters deep. Have students watch for patterns in the interactions between the monk seal and other organisms. As they watch, students should record the organism the monk seal interacts with and describe the interaction they observe.

Video Links:

Fish Thieves Take Rare Seals’ Prey

https://youtu.be/S9XPICyN0_Q

https://www.youtube.com/watch?v=S9XPICyN0_Q

https://safeshare.tv/x/ss683e0a7d25b5d#

Teacher questions:

What organisms does the monk seal eat in the video?
What other species interact with the seal while it's hunting?
Do any animals attempt to steal or share the seal’s catch?
What impact does their behavior have on the seal’s hunting success?
Do you notice any cooperation or neutral interactions among the organisms as the seal hunts?
Could any of these relationships eventually become harmful or helpful?�

See Student Journal page 2

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Reason

How would you categorize the relationships between the monk seal and the octopus, eel, and triggerfish?

How would you categorize the relationship between the monk seal and the sharks?

What is different about these relationships?

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Reason

Caribbean Cleaners

What is different between the relationships shown in this video and the monk seal video?

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Communicate

How might these patterns of interactions be found in different ecosystems around the world?

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Teacher Overview: Episode 2

Phenomenon: The populations of fox and rabbits interact in expected patterns.

Learning Goal: Students will construct an explanation for the patterns of the prey and predator interaction between the rabbits and the fox.

CCCs:� Use the CCCs as a lens to help focus your lesson, questions, discussion, etc.

Patterns: Students identify and analyze recurring predator-prey patterns in population changes over time.

Cause and effect: Students explore how predator-prey interactions cause shifts in population size and ecosystem stability.

SEPs:� SEPs are actions that students complete to interact with the phenomena.

Analyzing and interpreting data: Students collect and analyze population data over time and interpret patterns.

Constructing explanations: Students construct explanations using data about how predator-prey interactions affect populations in ecosystems.

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Episode 2

Today’s Objective: I can construct an explanation for the patterns of the prey and predator interaction between the rabbits and the fox.

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Gather

Sort the animals into groups.

Gather

Students obtain information through a sorting activity to learn more about patterns in ecosystems.

Teacher suggestions: Students should not look at their student science journals until after the discussion of predator and prey has been established.

Hand each group of students a set of animal cards. These animals all live on Antelope Island in Utah. Have groups sort the cards and then share how they sorted the cards with the class. Depending on how the groups sorted the first time, have them sort again. If after several sorting groups, they have yet to sort animals into predators and prey, prompt them to sort the animals by what they eat or how they get their food. Discuss the difference between the two types of animals to generate the definition of the vocabulary words predator and prey.

Antelope Island Animal Sorting Cards

See Student Science Journal page 3

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Gather

Predator Prey

What do you wonder about the interactions between predators and prey?

Students ask questions about the relationship of predator and prey to guide their learning of patterns in ecosystems.

Teacher suggestions: Allow students to formulate questions, using the word bank, about the prey and predator relationship.

Word Bank: prey, predator, pattern, relationship, ecosystem, interaction, cause, effect, not enough, too many

Questions may include the following:

What is the pattern of the relationship between predators and prey?
Why is this pattern important in an ecosystem?
What patterns would we expect from their interactions?
What patterns happen in an ecosystem if there are too many predators?
What patterns happen in an ecosystem if there aren’t any predators?
What patterns happen in an ecosystem if all the prey dies?
What patterns happen in an ecosystem if there are many prey?
What effects might new predators have on the patterns of an ecosystem?

See Student Science Journal page 3

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Gather

Foxes and Rabbits Simulation

online simulator

Students participate in a simulation to obtain information about how predator-prey interactions affect population sizes.

Teacher suggestions: The purpose of the simulation is to gather data about the interactions between a predator population of foxes and a prey population of rabbits in a meadow ecosystem. Students will collect data as they complete 16 generations of the simulation.

Use the online Fox and Rabbit Simulator (teacher should run the simulation prior to students to understand what expectations to set for students. Review the “How the game works” section at the bottom of the page and determine if you want to use the simulation data tracking exclusively, or also use the student journal in tandem.)

OR

Use the physical simulation. See Student Science Journal page 4 (updated with simulations rules)

Teacher Support: Setting up the Game

Students will work in groups of 3–4.
Designate a meadow for each group. (The meadow should be approximately 50cm × 50cm. Could use masking tape to designate a space, or prepare a piece of paper of the proper size. A 12x18” piece of construction paper works well.)
Start the first round with 3 rabbits and 1 fox.

Teacher Support: Playing the Game

One student randomly distributes the 3 rabbit squares in the meadow.
Another student will take a fox square and drop it from a height of 10 to 15 cm (6 inches) above the rabbits in an effort to “catch” (land on) a rabbit.
When an animal dies, remove the card from the meadow. When a new baby is born, add a card to the meadow.
The foxes:

The fox will starve if it does not capture (land on) any rabbits.
The fox will survive if it captures (lands on) at least one rabbit.
The fox will reproduce if it lands on 3 or more rabbits at the same time: The fox will produce 1 baby fox for every 3 rabbits it captures (for example, 6 rabbits = 2 baby foxes) *You cannot combine rabbits caught by different foxes to produce an additional baby fox.
If all of the foxes starve in the same round, a new fox will migrate into the meadow next round.

The rabbits:

If a rabbit is landed on by a fox, it dies.
Each surviving rabbit produces one offspring for the next round. (For example: if 2 rabbits survive = add 2 new baby rabbits. 25 rabbits survive = add 25 new baby rabbits.)
If all rabbits are captured, 3 new rabbits will migrate into the meadow next round.
The surviving rabbits may be redistributed throughout the meadow at the beginning of each round.

Count and record the number of foxes and rabbits each round.
Each round represents one year, or a generation. The surviving rabbits may be redistributed throughout the meadow at the beginning of each round.
Continue for 16 generations and record the data for each generation.

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Reason

Graph the number of foxes and rabbits from generations 1-16.

What do you expect to happen during generations 17-25?

Explain your prediction.

Reason

Students analyze data on the graph, using patterns to predict the populations for generations and make a claim based on the data and supported by evidence.

Teacher suggestions: Have students make a double y-axis line graph using different colors to represent the fox and rabbits for 16 generations. Support the students when determining what scale to use for the different y-axes to meet the needs of the fox and rabbit data. Discuss patterns and relationships in the graph.

Teacher questions:

What pattern do you see in the rabbit (or fox) population?
How are the patterns of the two populations connected?
How do changes in the rabbit population affect the fox population?

Once students have made sense of generations 1-16 on the graph, have them predict the pattern they might see for the next 9 generations (or up to 25). Their claim should be based on the data and supported by evidence, demonstrating their understanding of the prey/predator relationship.

Teacher questions:

Based on the patterns, what do you predict will happen in the next few generations?
What could happen to both populations if there are too many foxes? Too few?
If the rabbit population disappeared one year, what would happen to the fox population the next year?

See Student Science Journal page 5

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Communicate

What is the predator/prey relationship between the fox and the rabbits?

Use data to support your answer.

What might happen to the ecosystem if a new, more powerful predator was introduced into the ecosystem?

Communicate

Students will individually construct an explanation of the predator/prey relationship between the fox and rabbit, using data to support their answer. Using the patterns they noticed in the simulation, students will also make a prediction of what would happen to the ecosystem if a new, more powerful predator were introduced into the ecosystem.

Teacher Suggestions:

Have students discuss the following question:

How does the graph show the interaction between predator and prey? What patterns are shown? Explain using specific data points.

Individually, students will construct an explanation for:

Write a claim based on the data. Support your claim with evidence and reasoning.
What might happen to the ecosystem if a new predator, such as a wolf, enters the meadow? Assume that the wolf could capture many more rabbits than a fox.

Sentence Stems for writing a claim:

The relationship between predator and prey is...
The data shows that when the number of (rabbits/foxes) (increased/decreased), the (other population)...
This pattern shows that predators depend on prey because...
If there are too few prey, then...�

Teacher Support: This video supports understanding of how predator and prey populations fluctuate in relation to one another.

Predator Prey Cycles Video:

https://www.youtube.com/watch?v=NYq2078_xqc

https://safeshare.tv/x/ss5f3e9bc0c9db7

Formative Assessment

Students should create an accurate graph from the data. Students’ analysis should demonstrate an understanding of the patterns of the prey/predator relationship, using specific data from their graph/charts.

See Student Science Journal page 6

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Teacher Overview: Episode 3

Phenomenon: Snowy owl populations are affected by lemming populations.

Learning Goal: Students will construct a written explanation of the pattern of the prey/predator relationship between snowy owls and lemmings.

CCCs:� Use the CCCs as a lens to help focus your lesson, questions, discussion, etc.

Patterns: Patterns of change in predator and prey populations can be used as evidence to predict future population trends.

Cause and effect: Changes in the availability of prey cause changes in the population size of predators.

SEPs:� SEPs are actions that students complete to interact with the phenomena.

Asking questions and defining problems: Students analyze population graphs to identify patterns.

Analyzing and interpreting data: Students read an article to help make sense of data on a graph.

Constructing explanations: Students use data and reasoning to explain predator-prey population patterns.

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Episode 3

Today’s Objective: I can construct an explanation of the pattern of the relationship between snowy owls and lemmings.

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Gather

Students obtain information about snowy owl and lemming populations and ask questions based on their observations.

Teacher suggestions: Have the students observe the graph of the snowy owl and lemming populations. They will use their understanding from the simulation to ask questions about the prey and predator relationship.

Teacher questions:

What patterns do we see?
What happens to our pattern when the lemming population increases?
What might be causing the snowy owl population to fluctuate? Would you expect this pattern to continue?
Why are there some years without any lemmings or snow owls? What is causing this pattern?
Does the graph show a predictable pattern?

See Student Science Journal page 7

Teacher Background Information: A well-studied predator-prey relationship is that of the snowy owl and the lemmings, a type of rodent, that are their prey. Lemming populations go through cycles of growth and decline. When lemming populations become too large, they consume all of the moss that is their food. Without the moss, the lemmings starve and the population crashes. This cycle repeats every three to four years. Snowy owls are predators that rely on lemmings for food. Snowy owls will only reproduce if lemming populations are large enough for the owls to have enough food to feed both themselves and their chicks.

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Reason

Snowy Owls

How does the article help explain the information on the graph?

Reason

Students evaluate information from an article about the recent spike in snowy owl populations to make sense of the graph and identify patterns.
Students construct explanations for patterns using the graph and article.

Teacher suggestions: Have students identify patterns and explain them. They should also explain what might be happening when there were no snowy owls nests on Bylot Island.

Website article link: https://www.theguardian.com/environment/2014/feb/24/snowy-owl-lemming-population-us-canada

Teacher questions:

What causes the lemming population to decline so dramatically?
How does a change in lemming population affect snowy owl reproduction?
Do lemming populations rise and fall randomly, or do they follow a pattern? What is that pattern?
Based on the article, what kind of pattern might you expect to see in snowy owl populations?
How are the population changes of lemmings and snowy owls connected?
What evidence from the article shows a repeating cycle in predator and prey populations?

Teacher Background: Summary of Article:

Lemmings and Snowy Owls: A Predator–Prey Relationship

Cyclical Population Booms

Every 3–5 years, lemming populations experience a rapid boom, reaching incredibly high densities across Arctic tundra

Effects on Owl Reproduction

During these boom years, snowy owls feast on abundant lemmings: nest sites have been found with dozens of lemming carcasses .
This rich food supply enables snowy owls to lay larger clutches and fledge more young, leading to higher owl population growth .

Irruptive Migration Events

In boom years, an unusually high number of young owls is produced. These juveniles sometimes migrate far south—making what’s called an "irruption"—even reaching the northern United States

Decline and Population Crash

After lemming populations crash due to overconsumption or predation, food scarcity causes owl reproduction to fail in subsequent years

True Predator–Prey Cycle

The lemming–snowy owl relationship follows a classic predator-prey cycle: high prey numbers support high predator numbers, which then reduce prey, leading to fewer predators

Summary Statement

When lemming populations boom, snowy owls thrive, producing more chicks and sometimes migrating south. However, when lemmings crash, owl reproduction declines and their numbers fall, creating a cyclical predator–prey dynamic typical of Arctic ecosystems.

See Student Science Journal page 8

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Communicate

Describe the prey and predator relationship between snowy owls and lemmings.

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Teacher Overview: Episode 4

Phenomenon: The addition of wolves to a habitat affected the deer population.

Learning Goal: Students will construct an explanation for the prey/predator relationship of the wolves and deer and how the predator pattern affected the population.

CCCs:� Use the CCCs as a lens to help focus your lesson, questions, discussion, etc.

Cause and effect: Students identify how the presence or absence of predators causes observable effects on prey populations and ecosystem stability.

Patterns: Students recognize predictable changes in population data when predator-prey relationships shift over time.

SEPs:� SEPs are actions that students complete to interact with the phenomena.

Asking questions: Students ask questions about population patterns and ecological balance based on graphical data.

Analyzing and interpreting data: Students analyze graph data to detect trends and draw conclusions.

Constructing explanations: Students use data to argue whether predator introduction brought balance to the deer population and overall ecosystem.

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Episode 4

Today’s Objective: I will construct an explanation about how the predator/prey pattern of wolves and deer affect populations.

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Gather

Year	Wolf Population	Deer Population	Deer Offspring	Predation	Starvation	Deer Population Change
2000	10	2,000	800	400	100	+300
2001	12	2,300	920	480	240
2002	16	2,500	1,000	640	500
2003	22	2,360	944	880	180
2004	28	2,244	996	1,120	26
2005	24	2,094	836	960	2
2006	21	1,968	788	840	0
2007	18	1,916	766	720	0
2008	19	1,962	780	760	0
2009	19	1,982	790	760	0

Gather

Students obtain information as they study the paragraphs and the accompanying graph for patterns in the data.
Students will ask questions about the data and the impact on patterns.

Teacher suggestions: The graph and accompanying information found in the student journal will aid students to identify patterns. Have them then formulate questions they have about the data.

Teacher questions:

What patterns do we see on the graph?
Why were there too many deer?
What impact were the deer having on their environment?
Why were wolves introduced to the island?
What new patterns did the biologists expect to see once wolves were introduced to the island?
What impact did the introduction of the wolves have on the population of deer?
Why did the rate of starvation drop to zero?
Is this similar to other data we’ve studied?
Did the population gain stability once wolves were introduced?
What patterns would we expect to see if more years were added to the data table?

See Student Science Journal pages 9

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Reason

What was the effect of adding predators to the deer population?

What would have happened if wolves had not been introduced?

Reason

Students will analyze data to describe patterns and determine the effects of adding predators to the deer population.
Students develop arguments from evidence to support whether the wolves brought balance to the ecosystem.

Teacher suggestions: Have students graph the data to better make sense of the patterns when adding predators to a population. Have them discuss in groups whether the wolves brought balance to the ecosystem.

Teacher questions:

What patterns do you notice in the deer population over time?
What happened to the deer population before wolves were introduced? After?
How did the number of starvation cases change over time? What might explain this?
What trend do you see in the population after wolves were introduced? Is it consistent?
Does the graph suggest the ecosystem became more stable? How can you tell?
What data points support the idea that wolves impacted deer behavior and numbers?

See Student Science Journal pages 10

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Communicate

Did the wolves provide “balance” in this ecosystem?

What patterns in the data support your answer?

Communicate

Individually, students construct an explanation of the prey/predator relationship of the wolves and deer and how the predation pattern affected the population.

Teacher background: “balance” refers to a state where populations and resources are regulated so that no single species dominates to the point of destabilizing the system.

See Student Science Journal pages 10

Formative Assessment

Students’ explanations should demonstrate an understanding of the pattern of prey and predator interactions. They should discuss what balance in the ecosystem means and whether the wolves achieved balance.

Sentence Stems:

The introduction of wolves caused the deer population to...
As a result of predation, the deer experienced...
When wolves were added to the ecosystem, it affected the deer by...
According to the data, in year ___ the deer population was ___, which shows that...
One piece of evidence that supports my claim is...
I can tell the wolves helped/did not help balance the ecosystem because...

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Teacher Overview: Episode 5

Phenomenon: Organisms sometimes compete for the same resources

Learning Goal: Students will construct an explanation of examples where patterns of competition might exist in nature and how this could affect ecosystems.

CCCs:� Use the CCCs as a lens to help focus your lesson, questions, discussion, etc.

Cause and effect: Events in the simulation demonstrate how competition limits survival.

Patterns: Repeated outcomes in each round reveal predictable patterns of competition..

SEPs:� SEPs are actions that students complete to interact with the phenomena.

Analyzing and interpreting data: Students use outcomes from each round to evaluate how competition affects survival.

Constructing explanations: Students explain how resource competition shapes population dynamics in ecosystems.

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Episode 5

Today’s objective: I will construct an explanation about how patterns of competition in nature affect ecosystems.

Nearpod lesson 5 & 6 link: https://np1.nearpod.com/sharePresentation.php?code=a34e29a04696ab4458460d15cb3bf4d2-1&oc=user-created&utm_source=link

Episode 5

Time: 60 minutes

Phenomenon: Organisms sometimes compete for the same resources.

Performance Expectation(s): Students will construct an explanation with their partners, examples where patterns of competition might exist in nature and how this could affect ecosystems.

Materials and Set up:

Candy Competition Record Sheet (See Student Science Journal page 11)
Candy Competition Partner Instructions (The colors match the Original bag of Skittles. This resource was created to be printed or projected. Download a copy to edit if you are using something other than Skittles)
Divide students into groups of 2

Each set of partners will need the following:

1 bowl
⅓ to ½ cup Skittles*
2 spoons
2 small cups

*Teacher suggestions: To accommodate allergies, etc., M&Ms have been replaced with Skittles. You could also use jellybeans, colored beads, centimeter cubes, or other small, colorful objects.

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Gather

Are you ready to compete?

Gather

Students obtain information about patterns of competition by participating in a simulation of organisms competing for the same resources.

Teacher Preparation:

Arrange students into pairs and assign each student in the pair as either partner #1 or partner #2.
Arrange students so that all Partner #1s are facing one direction and all Partner #2s are facing the opposite direction. (Partner #1 and #2 will have different directions, so this seating will allow each partner to only see the directions meant for them.)
Give each pair of students one bowl with Skittles candies, two plastic spoons, and two small cups. (Provide expectations for how students should interact with materials before passing them out.)
Before simulation, you need to determine how many candies is “enough food” for survival. This number should vary based on how many candies students are supplied with. It is expected that some students will not collect this amount of food and will not survive during some rounds. Ideas for determining amount of food for survival include:

-Teacher assigns a set number of “food” necessary for survival for each round.

OR

-Before the simulation starts, have students write down a number between 3-8. This number becomes the amount of “food” that student needs to survive.

Simulation Instructions:

Before each round: Show each partner what they will be collecting during that round. (partners should not know what the other is collecting)
Begin the round: Students will collect as many candies as possible in 30 seconds. Students will pick up candies one piece at a time, using only their spoon. After 30 seconds, it is suggested to end the round by saying “spoons down”.
After each round: Students will fill in the first two boxes of the Candy Competition Record Sheet and return the Skittles to the bowl.

See Student Science Journal page 11

Candy Competition Partner Instructions

Round 1

Partner 1: Pick up orange Skittles

Partner 2: Pick up green Skittles

Round 2

Partner 1: Pick up yellow and orange Skittles

Partner 2: Pick up yellow and green Skittles

Round 3

Partner 1: Pick up red Skittles

Partner 2: Pick up red Skittles

Round 4

Partner 1: Pick up purple Skittles

Partner 2: Scoop as many Skittles as you can of any color

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Reason

When were both “organisms” able to survive?

When was it difficult for both “organisms” to survive?

Why was it easier to survive sometimes and not other times?

Reason

Students evaluate information from the simulation to explore the pattern of competition.

Teacher suggestions: Discuss the third box of the Candy Competition Record Sheet.

For the question “Were you both able to collect enough “food” to survive? Why or why not?” You need to determine how many candies is “enough food” for survival. This number should vary based on how many candies students are supplied with. It is expected that some students will not collect this amount of food and will not survive during some rounds.

Ideas for determining amount of food for survival include:

-Teacher assigns a set number of “food” necessary for survival for each round.

OR

-Before the simulation starts, have students write down a number between 3-8. This number becomes the amount of “food” that student needs to survive.

Teacher questions:

When were both “organisms” able to survive?
When was it difficult for both organisms to survive?
What was the difference?

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Reason

Discuss with your partner where patterns of competition might exist in nature and how this could affect ecosystems.

Reason

Students communicate information with partners examples where patterns of competition might exist in nature and how this could affect ecosystems.

Teacher Suggestions: Discuss the fourth box of the Candy Competition Record Sheet. Although student background knowledge will support this discussion, there may be misconceptions about what animals live in what habitats and what they actually eat. Examples have been provided if discussion needs support.

Examples of animal interactions for each round:

Round 1: Two animals live in the same habitat, but eat different foods

Grassland/Savanna Ecosystem

Zebras: eat grasses

Giraffes: eat leaves from tall acacia trees

Temperate Forest Ecosystem

Black Bears: eat berries, insects, small animals, and plants (omnivores)

White-tailed Deer: eat roots, tubers, and insects

Desert Ecosystem

Coyotes: eat small mammals, fruit, and remains of dead animals

Lizards: eat insects

Round 2: Two animals live in the same habitat, eat some shared foods and some unique foods.

African Savanna Ecosystem

Impala: eats young grasses, shrubs, and low-hanging leaves

Wildebeest: eats young grasses and mature, coarse grasses

Deciduous Forest Ecosystem

Cottontail Rabbit: eats acorns and woody twigs

Wild Turkey: eats acorns, insects, and berries

Tropical Rainforest Ecosystem

Howler Monkey: eats fruits, young leaves, and flowers

Keel-billed Toucan: eats fruits, insects, and eggs

Round 3: Two animals live in the same habitat and eat the same foods.

Forest Ecosystem

White-tailed Deer: eats leaves, twigs, and bark

Moose: eats leaves, twigs, and bark

Wetlands Ecosystem

Great Blue Herons: eats fish and frogs

Egrets: eats fish and frogs

Tundra Ecosystem

Snowy Owls: eats lemmings and other small mammals

Arctic Foxes: eats lemmings and other small mammals

Round 4: Two animals live in the same habitat, one eats many things, and the other eats only one thing that is also eaten by the other animal.

Temperate Forest Ecosystem

Koala: eats almost exclusively eucalyptus leaves

Possum: eats fruits, flowers, leaves-including eucalyptus leaves

Grassland Ecosystem

Canada Lynx: eats almost entirely snowshoe hares

Coyote: eats hares, rodents, fruit, and remains of dead animals

Wetlands Ecosystem

Snail Kite (bird of prey): eats apple snails

Raccoon: eats snails, eggs, insects, fruit

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Communicate

Construct an explanation describing patterns of competition between organisms in the rainforest ecosystem.

How might this affect organism survival ?

Communicate

Students construct an explanation describing patterns of interaction between organisms in the rainforest ecosystem and how this interaction might affect resource availability.

See student science journal page 12

Formative Assessment

Students should communicate that sometimes organisms consume different foods, but sometimes organisms compete for resources when they rely on the same food for survival.

In the passage, competition happens between the big cats themselves, and also with the anaconda. These patterns of competition can impact organism survival because when more than one species is competing for the same resource, another species might not get the resources they need to survive. Anacondas, because of their strength, have a much wider range of prey, which makes them less likely to suffer due to competition for resources.

In the next episode, students will see that an organism is more likely to survive if it has advantages such as size, speed, aggression, etc. This is not necessary for students to explain in this episode, but is good for knowledge building, if it comes up.

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Teacher Overview: Episode 6

Phenomenon: The population of red squirrels and coyotes was affected by the introduction of gray squirrels into their habitat.

Learning Goal: Students will construct an explanation of how introduction of an invasive species can affect population patterns.

CCCs:� Use the CCCs as a lens to help focus your lesson, questions, discussion, etc.

Patterns: Students will look for patterns in data of red squirrels, gray squirrels, and coyotes.

Cause and Effect: Students explore how the introduction of gray squirrels affected red squirrel and coyote populations

Stability and Change: Students analyze how ecosystems change over time due to the competition between native and invasive species.

SEPs:� SEPs are actions that students complete to interact with the phenomena.

Analyzing and interpreting data: Students interpret data tables showing population changes.

Construct an explanation from evidence: Students develop claims supported by evidence to explain observable patterns in competition with invasive species.

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Episode 6

Today’s objective: I will construct an explanation for patterns of interaction between red squirrels and gray squirrels

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Gather

Students obtain information and ask questions about gray and red squirrels and coyote populations to explore the pattern of competition from invasive species .

Teacher Support: Have students look at the data in the student journal to explore patterns of competition. This particular data will help students to explore the competition pattern associated with invasive species. Facilitate a discussion about the data to help them develop an understanding of the impact of invasive species. Do not give students any information about the differences between red and gray squirrels at this time.

Teacher Questions:

What is the difference between a native and invasive species?
What patterns do we see in the data?
Why did the number of red squirrels decrease when the gray squirrel numbers increased?
What is the relationship between the predators and squirrels?
Why did the number of coyotes increase and then decrease?
Is this an expected pattern for a prey/predator relationship? Why or why not?
Even though there were plenty of squirrels, why did the population of coyotes decrease?
What information about the different squirrel populations do we need to make sense of these numbers?

See Student Science Journal page 13

Teacher Background Information: Different species fight to survive and breed. Habitats have limited amounts of resources needed by organisms, and organisms must compete with other organisms in order to survive. A niche is a particular place occupied by an organism within an ecosystem. Similar species will occupy similar niches. For example, red squirrels and gray squirrels are two different species. When they come into contact, they begin to compete for resources. The gray squirrel is larger with a length of 23–30 cm compared to red squirrels, which average 19–23 cm long. Gray squirrels are a highly adaptive species. They are stronger and faster than red squirrels. Red squirrels are native to England. Gray squirrels were brought to England from America and released by aristocrats onto their estates because they were easier to see and hunt. Coyotes are natural predators of squirrels.

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Reason

What is the relationship between the gray and red squirrels?

What data supports your claim?

Reason

Students analyze data about the difference between red and gray squirrels to look for patterns.

Teacher suggestions:

Optional: Have students create a line graph of the data (using a different color for each organism) so they can better analyze the information and recognize patterns in the data. For a blank graph, see student science journal page 18.

Have students read the information about the differences between red and gray squirrels in the student journal on page 14. They will use this new information to analyze the patterns in the data from the chart and/or graph and make sense of competition of invasive species.

Students develop arguments from evidence the patterns they see in the data and the relationship between the gray and red squirrels.

Teacher Questions:

After reading the differences between gray and red squirrels, how might those differences explain the patterns in the data?
Does one squirrel have an advantage over the other?
What are the advantages?
What are the squirrels competing for?
How does this new information help you predict how the squirrels interact with the coyote?

See Student Science Journal page 13-14

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Communicate

Why did the red squirrel and coyote populations dwindle while the gray squirrel population grew?

Communicate

Individually, students evaluate information from the data table and the information about red and gray tree squirrels to argue from evidence about competition patterns to explain why the red squirrel and coyote populations dwindled while the gray squirrel population grew.

See Student Science Journal pages 13-14

Formative Assessment

Students’ arguments should demonstrate an understanding of the effect of one organism on the population of a competing population and the prey/predator relationship. As they gray squirrels grow in population, the red squirrel populations decrease because of the competition for resources. Because the gray squirrels are bigger, faster, and more aggressive, the red squirrels are easier prey for the coyotes. As the red squirrel populations decrease, the coyote populations also decrease because they are not getting enough food from the diminished red squirrel populations.

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Teacher Overview: Episode 7

Phenomenon: An ant defends a tree

Learning Goal: Students will construct an explanation for the patterns of animal interactions found in different ecosystems.

CCCs:� Use the CCCs as a lens to help focus your lesson, questions, discussion, etc.

Patterns: Similar types of interactions, such as mutualism, can be seen across many ecosystems.

Cause and Effect: Organisms interacting for mutual benefit often cause changes that improve survival for both species

SEPs:� SEPs are actions that students complete to interact with the phenomena.

Obtaining, evaluating, and communicating information: Students will gather and share data about mutualistic relationships.

Constructing explanations: Students will explain mutualistic interactions using evidence from videos and research.

Analyzing and interpreting data: Students will classify interactions from scenarios into mutualism, competition, or predation, based on observed patterns.

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Episode 7

Today’s objective: I will construct an explanation for the patterns of animal interactions found in different ecosystems.

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Gather

Ant Army Defends Tree

Gather

Students obtain information about the pattern of mutualism among different species by watching a video.

Teacher suggestions: Students will watch the video about the ants and the acacia tree. Have students take note of the relationship between two different species of organisms and facilitate a discussion about what was seen. When students describe the interaction as two organisms who benefit each other, you can give them the word mutualism to describe this relationship.

Video link: Amazing Symbiosis: Ant Army Defends Tree | National Geographic

https://www.youtube.com/watch?v=Xm2qdxVVRm4

https://www.youtube-nocookie.com/embed/Xm2qdxVVRm4

https://safeshare.tv/x/ss5e90c99890a5d

Teacher Questions:

What pattern of interaction was seen in the video?
How do the ants help the tree?
How do the ants benefit from living on the acacia tree?
What might happen to the tree if all of the ants died?
What would happen to the ants if the tree died?
How did this relationship develop?
What might we call the relationship between these two organisms?
Would you expect to find this same pattern in all acacia trees?
Would we expect to find this pattern of working together for the benefit of each in other ecosystems?

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Reason

What other examples of mutualism are seen in nature?

Be prepared to share your research.

Reason

In groups, students will obtain information to look for the patterns of different species working together for the benefit of each by finding examples of other phenomena of mutualism in nature.

Students construct explanations for a short presentation to share with their classmates the pattern of different species working together.

Teacher suggestions: Have students research other phenomena that show mutual benefit in nature and prepare a short presentation. Presentations might include an oral presentation, a poster, computer slideshow, etc. As each group shares, help other students pay attention to the patterns they are seeing in the interactions of the different organisms.

Resource List of mutualistic relationships:

Ants and aphids
Clownfish and anemones
Bacteria in human gut
Rhizobia bacteria and legumes
Termites and gut microbes
Lichen (algae and fungi)
Mycorrhizal fungi and plants
Cleaner fish and larger fish
Nitrogen-fixing bacteria and plants
Figs and wasps
Oxpecker birds and mammals
Humans and gut bacteria
Pollinators and fruit trees
Monarch butterflies and milkweed plants
Hummingbirds and flowers
Tsetse flies and protozoa
Goby fish and shrimp
Cleaner shrimp and fish
Birds and acacia trees
Bacteria and plants in the roots of rice
Mistletoe and trees
Sea urchins and kelp
Clams and bacteria
Bacteria in ruminant stomachs and ruminants
E. coli and humans
Algae and fungi in coral
Bacteria in termite gut and termites
Orchids and fungi
Ants and plants for nesting
Humans and domesticated animals
Algae and fungi in lichen
Bees and clover
Mammals and gut bacteria
Legumes and nitrogen-fixing bacteria
Trees and mycorrhizal fungi
Ants and fungi for food
Cleaner shrimp and turtles
Termites and fungi for food
Humans and domesticated plants
Plankton and algae
Cattle and grasses
Spiders and plants for webs
Bees and nectar producing flowers
Snails and algae
Bacteria and protozoa in soil
Sea anemones and clownfish for protection
Ants and fungi for antibiotics
Humans and livestock for food
Bacteria and fungi in soil
Algae and fungus in lichen
Ruminants and protozoa in their stomach
Bacteria and algae in sea sponges
Bees and apple trees
Beetles and fungi for food
Symbiotic microbes and hydrothermal vent creatures
Coral and zooxanthellae algae
Humans and domesticated animals for transportation
Ants and scale insects for honeydew
Monkeys and fruit trees
Symbiotic microbes and wood-eating insects

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Communicate

Predation

Mutualism

Competition

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Assessment