Lesson 2 | The Paleozoic Era
Student Labs and Activities
Page
26
Content Vocabulary
27
Lesson Outline
28
MiniLab
30
Content Practice A
31
Content Practice B
32
School to Home
33
Key Concept Builders
34
Enrichment
38
Challenge
39
Skill Practice
40
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Launch Lab
Geologic Time
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Name
Date
Launch Lab
Class
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
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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Geologic Time
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1. If you wanted to know about a great-great-great grandparent, what clues do you think
Name
Date
Content Vocabulary
Class
LESSON 2
The Paleozoic Era
Directions: 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, oxygenpoor 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
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
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.
Geologic Time
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Name
Date
Class
Lesson Outline
LESSON 2
The Paleozoic Era
A. 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
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)
Many
disappeared.
event.
invertebrates and some land animals
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
28
.
Geologic Time
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survived.
Name
Date
Class
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
.
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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.
Geologic Time
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Name
Date
MiniLab
Class
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
3. With a flexible tape measure,
measure the perimeter of each shape.
flat pancake shape. Form three pancake
shapes from an identical stick of clay.
Make all four shapes equal thicknesses.
Data and Observations
1. Compare Is the perimeter of the larger shape more or less than the combined
perimeters of the three smaller shapes?
2.
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Key Concept How might the formation of Pangaea have affected life on Earth?
Geologic Time
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Analyze and Conclude
Name
Date
Content Practice A
Class
LESSON 2
The Paleozoic Era
Directions: 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
1.
2.
Early
Paleozoic
3.
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4.
P
A
L
E
O
Z
O
I
C
5.
6.
Middle
Paleozoic
7.
8.
E
R
A
9.
10.
Late
Paleozoic
11.
12.
Geologic Time
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Name
Date
Class
Content Practice B
LESSON 2
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?
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?
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Geologic Time
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8. Why did plants need to live in water during the Middle Paleozoic?
Name
Date
Class
School to Home
LESSON 2
The Paleozoic Era
Directions: 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.
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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?
Geologic Time
33
Name
Date
Key Concept Builder
Class
LESSON 2
The Paleozoic Era
Key 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
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8. Which age is this time known as?
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
13. Which age is this time known as?
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?
34
Geologic Time
Name
Date
Key Concept Builder
Class
LESSON 2
The Paleozoic Era
Key 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.
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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.
Geologic Time
35
Name
Date
Class
Key Concept Builder
LESSON 2
The Paleozoic Era
Key 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.
When It Happened
What 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.
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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.
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Geologic Time
Name
Date
Key Concept Builder
Class
LESSON 2
The Paleozoic Era
Key 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.
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2. Describe what animal life was like during the age of fishes.
3. Describe what life was like during the Late Paleozoic.
Geologic Time
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Name
Date
Enrichment
Class
LESSON 2
Snowball Earth
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.
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 Sheets
Why Did Earth Freeze?
As 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.
Applying Critical-Thinking Skills
Directions: 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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Geologic Time
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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
Name
Challenge
Date
Class
LESSON 2
A Paleozoic Clock
The 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 Graph
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Determine 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.
Geologic Time
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Name
Date
Skill Practice
Interpret Data
Class
LESSON 2: 30 minutes
When did coal form?
Coal is fossilized plant material. When swamp plants die, they become covered by oxygenpoor 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?
Try It
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.
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?
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.
40
Key Concept What does fossil evidence reveal about the Paleozoic era?
Geologic Time
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4. During which geologic period did most of the coal form?