1. Lesson 1
Animal Adaptations
Lesson 2
Plants and Their Surroundings
Lesson 3
Changes in Ecosystems
The Big Idea
Why do plants and animals live in different places and what happens when those places change?
Why do plants and animals live in different places and what happens when those places change?
Chapter 4 Menu

2. adaptation hibernate camouflage mimicry Lesson 1 Splash
Look and Wonder
The snowcap hummingbird feeds on flowers in the rain forests of Costa Rica. Could this bird survive without its long and narrow beak?
No, it would not be able to reach the nectar that it needs for food.
Lesson 1 Splash

3. A camel’s hump stores fat for times when food is scarce.
What are adaptations?
A camel’s hump stores fat for times when food is scarce.
Discuss the Main Idea
Ask each student to think of an example of an animal with one or more characteristics that make the animal suitable for a specific environment.
Which characteristic helps this organism to survive?
Answers will vary. Students should support their responses by describing the organism’s adaptations.
How might this organism be affected if it were placed in another environment?
Possible answers: It might not be able to find food or water. It might not be able to protect itself.
Develop Vocabulary
Adaptation: Scientific vs. Common Use Tell students that the word adaptation refers to a characteristic or ability that an organism is born with. Although in everyday language people may speak of “adapting” to something, in science an adaptation is something that takes place over several generations within a species.
Read a Photo
Direct students to look at photos pg 167.
Which fox is better adapted to live in a desert ecosystem? Why?
The fennec fox, because it has shorter fur and larger ears, which help it to stay cool in a hot environment.
Use the Visuals
Have students look at the pictures of the kangaroo rat and camels on pages Ask:
Which type of environment are these organisms suited for?
A dry environment.
Which adaptation helps the camel to survive in the desert?
Its hump stores fat, which the camel uses for energy when food is scarce.
Quick Check (Critical Thinking)
How are an eagle’s claws and a giraffe’s neck similar?
Both are adaptations that help the animals to get food.
Lesson 1 a

4. The dormouse hibernates in its nest.
What are some other adaptations of animals?
The snow leopard blends into its environment to help it survive.
Discuss the Main Idea
In what ways does camouflage help an organism to survive?
Possible answers: Camouflage helps organisms to hide from predators to keep from being eaten. It helps the organisms to hide from prey so that they can catch the prey more easily.
Develop Vocabulary
Hibernate: Word Origin The word hibernate is from the Latin word hibernare, which means “to pass the winter.”
Camouflage: Word Origin The word camouflage is borrowed from the French word camoufler, which means “to disguise.” Animals that use camouflage try to disguise themselves to avoid predators.
Mimicry: Ask students to compare and contrast mimicry and camouflage. In both mimicry and camouflage, an organism copies an appearance or characteristic. Camouflage involves using an appearance similar to a background; mimicry involves using the appearance or behaviors of another organism.
Read a Photo
What adaptations help this snow leopard survive in its environment?
It uses camouflage to blend into its surroundings, making it difficult for prey to detect it. It also has fur to keep it warm in the cold environment.
Quick Check (Critical Thinking)
Why do you think most poisonous animals lack camouflage?
Poisonous animals usually do not need to blend in because predators avoid attacking them.
Lesson 1 b

5. These reef fish eat the algae that grow on the shells of sea turtles.
How else do animals survive?
Discuss the Main Idea
How do fleas interact with organisms harmfully?
A flea will feed on a organism’s blood, which causes the organism’s skin to become irritated. In this type of interaction the flea is helped, but the organism it lives on is harmed.
Use the Visuals
Ask students to look at the picture of the reef fish and sea turtle on page Ask:
Why do the fish follow the sea turtle?
They follow the sea turtle to feed on the algae that grows on the sea turtle’s shell.
How do you think the sea turtle benefits from the fish?
Possible answers: It gets the algae removed from its shell. It gets its shell cleaned.
Quick Check (Critical Thinking)
What other examples of harmful interactions can you think of?
Answers will vary, but should explain why the interaction is harmful to at least one of the animals.
These reef fish eat the algae that grow on the shells of sea turtles.
Lesson 1 c

6. How do adaptations help animals survive in their environments?
Main Idea
How do adaptations help animals survive in their environments?
Adaptations can help an animal to find food.
They can help animals to hide from predators.
They can help animals to hunt for prey.
They can allow animals to move in certain environments.
Main Idea
How do adaptations help animals survive in their environments?
Possible answers: Adaptations can help an animal to find food. They can help animals to hide from predators. They can help animals to hunt for prey. They can allow animals to move in certain environments.
Main Idea Review

7. Vocabulary adaptation camouflage hibernate mimicry
An adaptation in which one living thing looks
similar to another living thing is called _________.
A trait or behavior that helps a living thing
survive in its environment is an ___________.
To survive cold winters, some animals _________.
An animal that blends in with its surroundings
uses ___________.
Vocabulary
A) An adaptation in which one living thing looks similar to another living thing is called ___________.
B) A trait or behavior that helps a living thing survive in its environment is an _________.
C) To survive cold winters, some animals __________.
D) An animal that blends in with its surroundings uses __________.
A-mimicry, B-adaptation, C-hibernate, D-camouflage
adaptation
camouflage
hibernate
mimicry
Vocabulary Review

8. Suppose someone moved a polar bear to a rain forest
Suppose someone moved a polar bear to a rain forest. Predict how the bear might survive there.
Predict
It would take a very long time for a polar bear to adapt to this environment. The polar bear would not survive.
The bear would shed most of its fur and fat because the rain forest is very warm.
Predict
Use graphic organizer 4.
Suppose someone moved a polar bear to a rain forest. Predict how the bear might survive there.
• My Prediction: The bear would shed most of its fur and fat because the rain forest is very warm.
• What happens: It would take a very long time for a polar bear to adapt to this
environment. The polar bear would not survive.
Alternate Predict
What might happen to a desert animal if you moved it to the tundra?
It might not survive because it is adapted to live in a hot environment. The tundra is very cold.
Would you find an animal that hibernates in a tropical rain forest? Why or why not?
No, most animals hibernate to avoid the cold.
Which of the animals discussed above would survive without the other?
The mammals that fleas depend on would survive without fleas.
End of Lesson
G.O. Review

9. Vocabulary a

10. Vocabulary b

11. Vocabulary c

12. Vocabulary d

13. stimulus tropism Lesson 2 Splash Look and Wonder
Have you ever seen tree roots growing in air? Mangrove trees grow where no other trees can. They flourish in salt water, where the soil has little oxygen. Why would the mangrove tree need roots like these?
Mangrove roots provide support in unstable soils. They allow the mangrove tree to withstand currents and storms. They grow in the air to obtain nutrients for photosynthesis because the mud that they grow in does not contain enough nutrients.
Lesson 2 Splash

14. Tropism is the reaction of a plant to something in its environment.
How do plants respond to their environment?
Tropism experiment
Tropism is the reaction of a plant to something in its environment.
Discuss the Main Idea
Remind students that all organisms respond to changes in the environment. It is one of the basic life functions of living things.
Do plants respond to changes in the environment?
Yes
How do plants respond to light?
By growing toward the source of the light.
Develop Vocabulary
Stimulus: Scientific vs. Common Use Tell students that the word stimulus refers to something that causes a living thing to react. Students may be familiar with the common noun stimulant, which refers to something that accelerates activity, such as caffeine; they may know the adjective form, as in “stimulating” conversation.
Quick Check (Critical Thinking)
Some people think that plants respond to music. How could you test this hypothesis?
Test two plants. Grow one in a musical environment and the other in silence. The two environments should be otherwise identical. See which plant grows better.
Lesson 2 a

15. What are some plant adaptations?
Discuss the Main Idea
Which adaptations do cactus plants have?
Possible answers: spongy tissue that holds a large amount of water; think, waxy skin that reduces water loss through transpiration; sharp spines that protect the plants from animals.
Why do some trees lose their leaves in the fall?
Possible answers: to conserve energy; to prevent them from being exposed to the cold
Read a Photo
What adaptations help the prickly pear cactus live in the desert?
The prickly pear cactus has spines to protect it from animals, and thick, waxy skin to retain water.
Quick Check (Critical Thinking)
What might happen if you brought a desert plant into a humid greenhouse?
The plant would probably die because it does not have the right adaptations for the new environment.
A cactus has soft tissue that holds water just like a sponge. It also has a thick waxy cover to keep the water inside.
Lesson 2 b

16. Main Idea
How do plants respond to their environments? Give at least three examples.
Plants can grow toward or away from a stimulus, such as light, water, or gravity.
Main Idea
How do plants respond to their environments? Give at least three examples.
Plants can grow toward or away from a stimulus, such as light, water, or gravity
Main Idea Review

17. Vocabulary Tropism stimulus tropism
A _________ is something in the environment
that causes a living thing to react.
_________ is the reaction of a plant to
something in its environment.
Tropism
Vocabulary
A) A __________ is something in the environment that causes a living thing to react.
B) __________ is the reaction of a plant to something in its environment.
A-stimulus, B-tropism
stimulus
tropism
Vocabulary Review

18. How could you show that plants respond to changing temperatures?
Grow plants in different temperatures, with all other conditions being equal.
Problem and Solution
How could you show that plants respond to changing temperatures?
Observe the plants to determine how different temperatures affect growth.
Problem and Solution
Use graphic organizer 12.
How could you show that plants respond to changing temperatures?
Problem: Grow plants in different temperatures, with all other conditions being equal
Steps: Observe the plants to determine how different temperatures affect growth
Solution: Record your data and place plants in temperatures where they grow best.
Record your data and place plants in temperatures where they grow best.
End of Lesson
G.O. Review

19. Vocabulary a

20. Vocabulary b

21. accommodation endangered extinct Lesson 3 Splash Look and Wonder
The four-wing saltbush plant can adapt to harsh conditions. These seedlings are growing in dry, cracked mud. Was the soil always this dray? Why don’t other plants grow here?
Possible answer: Other plants do not grow here because they cannot survive in such dry conditions.
Lesson 3 Splash

22. What causes an ecosystem to change?
Mount Saint Helens in 1980
Mount Saint Helens in 1995
Discuss the Main Idea
What are some natural events that change ecosystems?
Possible answers: floods, volcanic eruptions, droughts, forest fires
How can living things change an ecosystem?
Possible answers: Large populations can reduce a food supply; people can cut down many trees and destroy a forest habitat.
Read a Photo
How do the two photos show a cause and effect?
The first photo was taken after the eruption of Mount Saint Helens; the second photo was taken after the ecosystem had recovered. The volcanic eruption caused a change to the ecosystem.
Quick Check (Critical Thinking)
How might an alligator benefit from a drought?
During a drought other animals might come to the gator hole looking for water. These animals will become prey for the alligator.
Lesson 3 a

23. concrete “reef balls” on the sand
How do people change ecosystems?
an airplane being sunk
concrete “reef balls” on the sand
a subway car being sunk
Manufactured Ecosystems
Discuss the Main Idea
What are some changes that harm ecosystems?
Possible answers: People may destroy habitats, use up resources, and produce pollution.
Develop Vocabulary
Deforestation: Tell the students that adding the prefix de- to the beginning of a word creates an antonym, or opposite, of the word. For example, deforestation means the act or the process of removing forests or trees.
Read a Photo
In what ways do people help rebuild underwater ecosystems?
By lowering old planes and train cars into the water, people can create artificial reefs. Once these objects are underwater, they provide a surface for marine organisms, such as algae, corals, and barnacles, to grow. Other organisms, such as fish, will then come to these artificial reefs to feed.
Use the Visuals
Have the students look at the photo of train cars on page Ask:
How could an old train car be used to rebuild the environment?
The train car is being used to create an artificial reef, which will increase the diversity of an underwater ecosystem.
Quick Check (Critical Thinking)
How are deforestation and overpopulation related to each other?
If there is human overpopulation, people may clear forested areas to build homes, factories, and roads.
Lesson 3 b

24. What happens when ecosystems change?
The passenger pigeon was hunted into extinction in 1914.
The Tasmanian tiger was declared extinct in 1936.
Discuss the Main Idea
What are the three main ways that an organism reacts to a dramatic change in an ecosystem?
The organism may adapt to the change, move away, or die out.
Develop Vocabulary
Accommodation: Scientific vs. Common Use Tell students that the word accommodation refers to an organism’s response to change. In common language, accommodation usually refers to something that satisfies a need, such as food or lodging.
Endangered: Have students research programs and organizations that work to protect endangered plants and animals. Have students report on the activities that help to protect these organisms.
Extinct: Word Origin The word extinct comes from the Latin word extinctus, which is the past participle of the Latin word extinguere, which means “wipe out or obliterate.” All members of a species that is extinct have died, or been “extinguished.”
Quick Check (Critical Thinking)
Why are plants usually the first organisms to spread to a new area?
Plants are producers. Once plants are established in a new area, they become a food source for consumers that will follow them to the new area.
Lesson 3 c

25. How can people prevent extinction?
The giant panda is an endangered species.
Discuss the Main Idea
What will happen to a species that is endangered it if does not produce offspring?
It will become extinct.
Quick Check (Critical Thinking)
What would happen to pandas if scientists did not help them have cubs?
Pandas would remain endangered or become extinct.
Lesson 3 d

26. Natural events: storms, earthquakes, droughts, volcanic eruptions
Main Idea
List six events that change ecosystems. Choose four natural events and four caused by people.
Natural events: storms, earthquakes, droughts, volcanic eruptions
Changes caused by people: farming, mining, land development, pollution
Main Idea
List six events that change ecosystems. Choose three natural events and three caused by people.
Natural events: storms, earthquakes, droughts, volcanic eruptions; changes caused by people: farming, mining, land development, pollution
Main Idea Review

27. Vocabulary accommodation endangered extinct
When a species no longer exists, it is
__________________.
An individual’s response to change is called
an __________________.
If a living thing has few of its kind left it is __________________.
Vocabulary
A) When a species no longer exists, it is __________.
B) An individual’s response to change is called an _________
C) If a living thing has few of its kind left it is __________
A-extinct, B-accommodation, C-endangered
accommodation
endangered
extinct
Vocabulary Review

28. What happens when a forest is cut down to build a power plant?
Cause and Effect
Organisms that live in the forest must move to a new ecosystem, accommodate the power plant, or become extinct.
A forest is cut down to build a power plant.
Main Idea
Cause and Effect
Use graphic organizer 9.
What happens when a forest is cut down to build a power plant?
Cause: A forest is cut down to build a power plant.
Effect: Organisms that live in the forest must move to a new ecosystem, accommodate the power plant, or become extinct.
End of Lesson
G.O. Review

29. Vocabulary a

30. Vocabulary b

31. Vocabulary c