Lesson 2 | The Paleozoic Era...The Paleozoic era is the oldest era of the Phanerozoic eon. It lasted about 291 million years, more than half of the entire Phanerozoic eon. How would

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Student Labs and Activities Page Appropriate For:

Launch Lab 26 all students

Content Vocabulary ELL 27 all students

Lesson Outline ELL 28 all studentsMiniLab 30 all studentsContent Practice A 31 AL AL AL

Content Practice B 32 AL OL BL

School to Home 33 all studentsKey Concept Builders 34 AL AL AL

Enrichment 38 all studentsChallenge 39 AL AL BL

Skill Practice 40 all students

Assessment

Lesson Quiz A 41 AL AL AL

Lesson Quiz B 42 AL OL BL

Teacher Support

Answers (with Lesson Outlines) T4

AL Approaching Level OL On Level BL Beyond Level ELL English-Language Learner

Teacher evaluation will determine which activities to use or modify to meet any ELL student’s proficiency level.

Lesson 2 | The Paleozoic Era

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Launch Lab LESSON 2: 20 minutes

What can you learn about your ancestors? Scientists use fossils and rocks to learn about Earth’s history. What could you use to research your past?

Procedure 1. Write as many facts as you can about

one of your grandparents or other older adult family members or friends.

2. What items, such as photos, do you have that can help you?

Data and Observations

Think About This 1. If you wanted to know about a great-great-great grandparent, what clues do you think

you could find?

2. How does knowledge about past generations in your family benefit you today?

3. Key Concept How do you think learning about distant relatives is like studying Earth’s past?

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The Paleozoic EraDirections: On each line, write the term from the word bank that correctly replaces the underlined words in each sentence. NOTE: You may need to change a term to its plural form.

Cenozoic era coal swamp inland sea

Mesozoic era Paleozoic era supercontinent

1. During the Late Paleozoic, there were many wet, oxygen-poor environments where, over time, plant material changed into coal.

2. In the Early Paleozoic, there were many bodies of water that formed when ocean water flooded continents.

3. The middle era of the Phanerozoic eon occurred after the Paleozoic era.

4. The earliest era of the Phanerozoic eon includes the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian periods.

5. Formed in the Late Paleozoic, Pangaea was an ancient landmass that separated into present-day continents.

6. The most recent era of the Phanerozoic eon began after the Mesozoic era.

Content Vocabulary LESSON 2


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The Paleozoic EraA. Early Paleozoic

1. The oldest era of the Phanerozoic eon is the .

2. The middle era of the Phanerozoic eon is the .

3. The is the youngest era of the Phanerozoic eon.

4. Organisms from the Early Paleozoic were that lived

in the oceans. These animals have no .

5. During the Early Paleozoic, the shapes of the were different from today.

6. During this time, Earth’s climate was .

7. Rising oceans flooded the continents, forming shallow .

8. During the Early Paleozoic, the landmass that would become North America was

near the .

B. Middle Paleozoic

1. Although the Early Paleozoic ended with mass extinction, many

survived.

2. Animals with backbones, or , evolved.

a. Some of the earliest vertebrates were .

b. In addition to fishes, insects evolved, and Earth’s first

appeared.

3. Major collisions between occurred at this time.

Some of these collisions formed the .

C. Late Paleozoic

1. The Middle Paleozoic ended in a(n) event.

Many invertebrates and some land animals disappeared.

2. Fishlike organisms evolved into organisms that had and could breathe air.

a. These had thick skins and strong limbs.

b. Amphibians must return to water to .

Lesson Outline LESSON 2


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Lesson Outline continued

3. evolved toward the end of the Paleozoic era.

a. Reptiles were the first animals that did not require for reproduction.

b. Reptiles can spend all their time on .

4. During the late Paleozoic period, tropical forests grew in

along shallow inland seas.

a. When the plants died, they sank into swamps called

swamps.

b. A coal swamp is a(n) -poor environment where, over time, plant material changes into coal.

5. Earth’s continents moved close together and formed a

giant .

a. A supercontinent is an ancient landmass that separated into

present-day .

b. This Paleozoic supercontinent has been named .

6. The largest known mass extinction on Earth occurred at the end of the

era.

a. During this mass extinction, percent of marine life-forms and 70 percent of all life on land became extinct.

b. Some scientists hypothesize that this mass extinction was caused by a sudden

change.

c. Other scientists propose that a large or large volcanic eruptions resulted in sunlight being blocked for a long period of time.


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MiniLab LESSON 2: 20 minutes

What would happen if a supercontinent formed?Many organisms live along continental coastlines. What happens to coastlines when continents combine and form a supercontinent?

Procedure 1. Read and complete a lab safety form.

2. Form a stick of modeling clay into a flat pancake shape. Form three pancake shapes from an identical stick of clay. Make all four shapes equal thicknesses.

3. With a flexible tape measure, measure the perimeter of each shape.

Data and Observations

Analyze and Conclude 1. Compare Is the perimeter of the larger shape more or less than the combined

perimeters of the three smaller shapes?

2. Key Concept How might the formation of Pangaea have affected life on Earth?


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LESSON 2

The Paleozoic EraDirections: Complete this chart by choosing phrases from the list and writing them on the correct lines. Some terms may be used more than once or not at all.

age of amphibians age of fishes

age of invertebrates coal swamps appear

cockroaches evolve first plants appear

all life in oceans mass extinction

no life on land reptiles evolve

Content Practice A

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

Early Paleozoic

Middle Paleozoic

Late Paleozoic

PALEOZOIC

ERA


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The Paleozoic Era Directions: Answer each question on the lines provided.

1. Which type of animal marks the Early Paleozoic?

2. Where did invertebrates live during the Early Paleozoic?

3. What was Earth’s climate like during the Early Paleozoic?

4. What covered much of North America during the Early Paleozoic?

5. What happened to animal life at the end of the Early Paleozoic?

6. Which type of animal marks the Middle Paleozoic?

7. What evolved on land during the Middle Paleozoic?

8. Why did plants need to live in water during the Middle Paleozoic?

9. What happened to marine invertebrates at the end of the Middle Paleozoic?

10. Which type of animal marks the Late Paleozoic?

11. What is special about the eggs of reptiles that allows them to live entirely on land?

12. What was the climate like at the end of the Late Paleozoic?

13. What is a possible reason that scientists give for the sudden mass extinction during the

Late Paleozoic?

Content Practice B LESSON 2


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The Paleozoic EraDirections: Use your textbook to answer each question.

1. The Paleozoic era is the oldest era of the Phanerozoic eon. It lasted about 291 million years, more than half of the entire Phanerozoic eon.

How would you describe Earth during the Early Paleozoic?

2. During the Middle Paleozoic, a mass extinction killed many marine invertebrates. Some, however, survived.

What animals were dominant during the Middle Paleozoic? What was unique about these animals?

3. The Late Paleozoic is often called the age of amphibians. By adaptation, amphibians were able to breathe air and reproduce on land.

Coal forests also developed during the Late Paleozoic. What are coal forests?

4. Scientists hypothesize that in the Paleozoic era, the continents drifted together to form the giant landmass called Pangaea.

How might the formation of Pangaea have led to an entire species dying?

School to Home LESSON 2

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The Paleozoic EraKey Concept What major geologic events occurred during the Paleozoic era?

Directions: Answer each question on the lines provided.

Early Paleozoic

1. Which age is this time known as?

2. What was the climate like?

3. What happened to the seas during this time?

4. What two things resulted from this change in sea level?

5. Where was North America located?

6. Where did animal life exist?

7. Which type of animals existed?

Middle Paleozoic


9. What happened between moving continents?

10. What was created from this movement?

11. Which type of animals further evolved in the seas?

12. Which type of animals evolved on land?

Late Paleozoic


14. What was the climate like near the end of this time?

15. What landmass formed during this time?

16. Which type of animals evolved on land toward the end of this time?

17. What happened to 70 percent of all life-forms on land at the end of this time?

Key Concept Builder LESSON 2

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The Paleozoic EraKey Concept What major geologic events occurred during the Paleozoic era?

Directions: On the line before each event, write E if it describes the Early Paleozoic, M if it describes the Middle Paleozoic, or L if it describes the Late Paleozoic.

1. The center of the land became drier and cooler.

2. The Appalachian Mountains formed.

3. A warm climate characterizes this time.

4. Pangaea formed.

5. A massive meteorite might have hit Earth.

6. Vast inland seas formed.

7. There were many major collisions between continents.

8. Rising seas flooded the continents.

9. A supercontinent formed.

10. Many different types of fishes evolved.

11. There might have been massive volcanic eruptions.

12. The first plants appeared.

13. North America straddled the equator.

14. Dense forests grew along inland seas.

15. Plants were only in water.

16. Coal swamps formed.

17. Most of North America was covered by an inland sea.

LESSON 2Key Concept Builder


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The Paleozoic EraKey Concept What does fossil evidence reveal about the Paleozoic era?

Directions: Put a check mark in the space that correctly identifies what rock and fossil evidence reveal about the Paleozoic era.

What HappenedWhen It Happened

Early Paleozoic

Middle Paleozoic

Late Paleozoic

1. Seventy percent of all life-forms on land become extinct.

2. All life is in the oceans.

3. It is the age of invertebrates.

4. Heavily armored fish evolve.

5. Reptiles evolve.

6. Cockroaches, dragonflies, and other insects evolve on land.

7. Dense forests grow along shallow inland seas.

8. It is the age of fishes.

9. New life-forms evolve along coral reefs.

10. It is the age of amphibians.

11. Ninety-five percent of marine life becomes extinct.

12. The first plants appear.

13. Coal swamps form.

14. The largest mass extinction in Earth’s history occurs.

Key Concept Builder LESSON 2


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The Paleozoic EraKey Concept What does fossil evidence reveal about the Paleozoic era?

Directions: Work with a partner to respond to each statement on the lines provided.

1. Explain what rock and fossil evidence reveals about Early Paleozoic organisms.

2. Describe what animal life was like during the age of fishes.

3. Describe what life was like during the Late Paleozoic.

LESSON 2Key Concept Builder


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Rocks deposited by glaciers are present throughout the world, even in tropical areas. This fact has led some scientists to hypothesize that Earth might have been completely frozen at some time. Evidence shows that a total global freeze might have occurred as many as four or five times. Scientists call these global freezes Snowball Earth, and they think that they most likely occurred between 580 and 750 mya.

Why Did Earth Freeze?One possible explanation for a massive

freeze lies with the plate tectonics theory. According to this theory, the same forces under Earth’s surface that cause earthquakes and volcanoes also move the continental plates. The continents moved together and apart and are still moving.

Before Snowball Earth, the continents were one giant continent, located near the

equator. The continent’s center, far away from the oceans, was dry. Then this large continent broke into three pieces, still near the equator. Because the centers of the new continents were much closer to the oceans, more rain fell there. The increased rainfall washed more carbon dioxide out of the air, making Earth’s temperatures drop and forming ice sheets in the polar regions.

Ice SheetsAs huge polar ice sheets grew larger,

their glaring white surfaces reflected the Sun’s heat from Earth, making temperatures fall further. When ice covered half of Earth’s surface, so much of the Sun’s radiation was deflected that temperatures plunged. This made the ice sheets grow larger until they covered the land and oceans completely.

Snowball Earth

LESSON 2Enrichment

Applying Critical-Thinking SkillsDirections: Respond to each statement.

1. During a global freeze, volcanoes would have continued to erupt. Volcanoes emit carbon dioxide, a greenhouse gas. Usually, evaporating moisture absorbs some carbon dioxide in the air. Water vapor also raises temperatures. Explain how this process would have changed with ice sheets covering all the oceans.

2. Predict Albedo is a measurement of the amount of radiation from the Sun that reflects off a surface. A higher albedo indicates that more radiation is reflected, meaning surface temperatures are lower. Note the albedo for the following surfaces: new pavement, 0.04; seawater, 0.10; forest, 0.14; dry desert, 0.37; sea ice, 0.60; and snow on ice, 0.80. Considering the effect that large ice sheets have on Earth’s climate, predict the effect that paving dry deserts would have on Earth’s climate.

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A Paleozoic ClockThe Paleozoic era encompasses six major periods—the Cambrian, Ordovician, Silurian,

Devonian, Carboniferous, and Permian. Research online to find information about each period of the Paleozoic.

Make a Circle GraphDetermine the percentage of the Paleozoic era that each period occupied. Prepare

a Paleozoic clock in the circle below. Mark off each period as a wedge in the circle graph. Label each wedge in order and write a title for the circle graph. Inside each wedge, write a description and give examples of the evolution of life-forms. Include a description of what the landmasses looked like and provide the continental names, if any. Draw a key that gives the percentage of time. This can be labeled in the wedge and/or color coded.

LESSON 2Challenge

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When did coal form? Coal is fossilized plant material. When swamp plants die, they become covered by oxygen-poor water and change to peat. Over time, high temperatures and pressure from sediments transform the peat into coal. When did the plants live that formed the coal we use today?

Interpret DataSkill Practice LESSON 2: 30 minutes

Learn It A bar graph can display the same type of information as a line graph. However, instead of data points and a line that connects them, a bar graph uses rectangular bars to show how values compare. Look at the bar graph in your textbook. Interpret the data to learn when most coal formed.

Try It 1. Carefully study the bar graph in your

textbook. Notice that time is plotted on the x-axis (as geologic periods), and that coal deposits (as tons accumulated per year) are plotted on the y-axis.

2. Use the graph and what you know about coal formation to answer the following questions.

Apply It 3. Which coal deposits are oldest? Which are youngest?

4. During which geologic period did most of the coal form?

5. Approximately how much coal accumulated during the Paleozoic era? The Mesozoic era?

6. Why are there no data on the graph for the Cambrian, Ordovician, and Silurian periods of geologic time?

7. Key Concept What does fossil evidence reveal about the Paleozoic era?

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Lesson Quiz A LESSON 2

The Paleozoic EraMultiple ChoiceDirections: On the line before each statement, write the letter of the correct answer.

1. The part of the Paleozoic era is often called the age of invertebrates. A. late B. early C. middle

2. covered much of Earth during the Early Paleozoic era. A. Glaciers B. Inland seas C. Mountain chains

3. The Middle Paleozoic era is often called the age of A. fishes. B. reptiles. C. amphibians.

4. The Appalachian Mountains began to form during the Paleozoic era. A. Late B. Early C. Middle

5. The major groups of animals that lived during the Late Paleozoic were the A. reptiles. B. amphibians. C. invertebrates.

6. Pangaea was a supercontinent that A. was located near the equator. B. made Earth’s climate warm and wet. C. was completely covered with swamps.

7. did NOT contribute to the mass extinction that ended the Paleozoic era. A. A meteorite impact B. Widespread ice sheets C. The formation of Pangaea

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Lesson Quiz B LESSON 2

The Paleozoic EraShort AnswerDirections: Respond to each statement on the lines provided.

1. Identify when the age of invertebrates occurred.

2. Define inland seas. Identify when they covered much of Earth.

3. State another name for the Middle Paleozoic era. Explain why it has this name.

4. Explain how and when the Appalachian Mountains formed.

5. Identify when the age of amphibians occurred.

6. Describe Pangaea and give its location.

7. Explain three factors that could have contributed to the extinctions in the Paleozoic era.

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Lesson 2 | The Paleozoic Era...The Paleozoic era is the oldest era of the Phanerozoic eon. It lasted about 291 million years, more than half of the entire Phanerozoic eon. How would