OVERVIEWStudents will understand how scientists use the rock record to construct Earth’s geologic history.

• Before Your Visit: Using videos, essays, and interactives, students will learn about the scientific process, and how geologists examine evidence to find out about the early Earth.

• During Your Visit: • In the Gottesman Hall of Planet Earth, students will use the Geologic

Time Scale as an entry point of exploring geologic history. • In the Fossil Halls, students will further investigate geologic history

and look for examples of index fossils listed on the Reference Table. • Back in the Classroom: Students will combine information collected

at the Museum with further research to make connections to a portion of the Geologic History of New York State Reference Table and create poster presentations.

BACKGROUND FOR EDUCATOREvidence for the development of Earth’s atmosphere includes:

• a specimen of a banded iron formation that helps tell the story of the oxygenation of the ocean and atmosphere;

• stromatolites, the fossilized remains of Earth’s first life forms, microbes that produced oxygen through photosynthesis; and

• a section of conglomerate rock that records Earth’s first prolonged glaciation.

BEFORE YOUR VISITUse these videos and related activities and resources to illustrate the process of science and to help students understand the formation of Earth.

Activity: Zircons: Time Capsules from Early Earthsciencebulletins.amnh.org/?sid=e.f.zircons.20100401Zircons are ancient minerals that typically exist as tiny crystals in rocks. The oldest Earth materials ever discovered, they contain clues about periods of geological time for which there is no direct evidence. This video shows scientists making hypotheses about conditions of early Earth based on zircons. Links to the activity and essay are located below and to the left of the video window.

Activity: The Rise of Oxygen sciencebulletins.amnh.org/?sid=e.f.rise02.20040301A 2.5 billion year old sedimentary formation in Ontario, Canada, records how much oxygen Earth’s early atmosphere contained. Use this video and the related activity and interactive, “Tour the Huronian Supergroup,” to explore how geologists collect evidence that they use to formulate and test hypotheses about the composition of the ancient atmosphere. Links to the activity and interactive are located below and to the left of the video window.

Gottesman Hall of Planet Earth Activities for Grades 9-12

Investigate Earth’s Geologic History

© 2012 American Museum of Natural History. All rights reserved.

NYS Physical Setting/Earth Science Core CurriculumPS 1.2j: Geologic history can be recon-structed by observing sequences of rock types and fossils to correlate bedrock at various locations.

PS 1.2h: The evolution of life caused dramatic changes in the composition of the Earth’s atmosphere. Free oxygen did not form in the atmosphere until oxygen-producing organisms evolved.

Plan how your students will explore the Gottesman Hall of Planet Earth using the student worksheets. Distribute copies of the worksheets and reference tables to students beforehand, and review them to make sure everyone understands the activi-ties. Have students work individually or in pairs as they explore the exhibition.

DURING YOUR VISITGottesman Hall of Planet Earth1st floor (45-60 minutes)Students will explore our planet’s geologic history, including formation of Earth and life in early Earth. Have them begin their investigation at the Hall’s Geologic Timescale. Working individually or in pairs, have them use the student worksheets to explore how our planet and its life forms evolved simultaneously over immense stretches of time. At each stop, students will identify the age of specimens and mark this on the timescale on their worksheets.

Wallach Orientation Theater & Fossil Halls 4th floor (30–45 minutes)Have students further investigate geologic history by watching the introductory video in the Orientation Theater and exploring the Fossil Halls. Have them look for examples of the index fossils listed on the reference tables.

BACK IN THE CLASSROOMWrap-Up Activity: Modeling Geologic Time

Students will combine information collected at the Museum with further research to make connections to a portion of the Geologic History of New York State Reference Table.

First, have students plot the age of specimens in questions 2, 4, 5, 6, 7, 9, and 10 on the Geologic History of New York State Reference Table.

Then, do the following activity with students to help them visualize the data.

materials: • clothespins or paperclips• 50 meters of thin rope or clothesline (length depends on size of classroom)• index cards with names and ages of Museum samples as well as other significant dates and occurrences from the

ESRT table (one per student or team)• red and black permanent markers • metric tape measure or meter stick

Using the red marker, mark out the clothesline in five equal sections, each representing one billion years. Be sure to allow space at each end to hold or attached the clothesline.

Using the black marker, divide each billion-year segment into 10 equal sections, each representing 100 million years.Attach the geologic time line along the perimeter of your classroom and have students or teams come up and attach their cards to the timeline.

Activity: Layers of Time Fossil Puzzle amnh.org/ology/features/layersoftime/Students can play this computer interactive to learn about how sedimentary rock layers are formed and how the history of life is written within rocks. There are three levels of difficulty and a seven-layer puzzle in which fossils serve as clues. Students can use a Check Your Work option to check their solutions. A shortened, print version of this activity is available at amnh.org /resources/rfl/pdf/dinoactivity_layers.pdf

Gottesman Hall of Planet Earth Activities for Grades 9-12

© 2012 American Museum of Natural History. All rights reserved.

Geologic Time Scale Start Here: Examine the geologic timeline of our planet.

Today, you will be investigating how current conditions on Earth are the result of our planet and its life forms evolving simultaneously over long stretches of time.

Formation of Earth Meteorites (samples #1-3): How old are they?

Four Density Blocks (#4–7): Lift the four blocks and compare their weights. Which is lightest? Heaviest? What can they tell us about the layers of Earth? What does this tell us about the way they formed?

The Oldest Known Rocks (#12): How old is it?

What does it contain and what does it tell scientists about early Earth?

Life in Early Earth Sulfide Chimneys (#26–30): Where are hydrothermal vents found, and how do they form? When did they form? Why do scientists think that life began at vents like these?

Gottesman Hall of Planet Earth Grades 9-12

Student Worksheet: Investigate Geologic Time

© 2012 American Museum of Natural History. All rights reserved.

1

23

4

56789

10

1

2

3

4

5

4.6 billion years ago 3.8 bya 2.6 bya 560 mya 250

today

65

Stromatolite (#14): How old is it?

What are stromatolites and what can they tell us about the early Earth?

Banded Iron (#15): How old is it?

Examine the “How do we know about the early atmosphere?” diagram. Label it to show how oxygen and iron composition changed over time.

The Oldest Fossil? (#16): Watch the video above about the evolution of microfossils and examine the fossil specimen. How old is it?

Pyrite-Bearing Conglomerate (#17), Gray-White Quartzite (#18), and Red Quartzite (#19): Compare the color and composition of the three samples. What type of rocks do you think they are? What can the color variations and composition of the Huronian Supergroup tell us about how the atmosphere has changed over time?

Glaciation Earliest Ice Ages (#20), Debris from Oldest Glaciers (#21), and Outcrop of Glacial Sediments (#22): How old are they?

How do these samples provide evidence of an early ice age?

Gottesman Hall of Planet Earth Grades 9-12

© 2012 American Museum of Natural History. All rights reserved.

6

7

8

9

10

Physical Setting/Earth Science Reference Tables — 2011 Edition 8

PLEISTOCENEPLIOCENE

MIOCENE

OLIGOCENE

EOCENE

PALEOCENE

LATE

EARLY

LATEMIDDLE

EARLY

LATE

MIDDLEEARLYLATE

MIDDLE

EARLY

LATE

MIDDLE

EARLY

LATE

MIDDLE

EARLY

LATE

EARLY

LATE

MIDDLE

EARLY

LATE

MIDDLE

EARLY

EARLY

LATE

GEOLOGIC HISTORY

ElliptocephalaCryptolithus

Phacops Hexameroceras ManticocerasEucalyptocrinus

CtenocrinusTetragraptus

Dicellograptus EurypterusStylonurus

B LA EC D G HF I J NK M

CentrocerasValcouroceras Coelophysis

(Index fossils not drawn to scale)

EraEon

PH

AN

ER

O-

ZO

ICP

RE

CA

MB

RI

AN

AR

CH

EA

NP

RO

TE

RO

ZO

IC

LATE

LATE

MIDDLE

MIDDLE

EARLY

EARLY

0

500

1000

2000

3000

4000

4600

Million years ago

CENOZOIC

MESOZOIC

PALEOZOIC

QUATERNARY

NEOGENE

PALEOGENE

CRETACEOUS

JURASSIC

TRIASSIC

PERMIAN

CA

RB

ON

IF-

ER

OU

S

DEVONIAN

Period Epoch Life on Earth

SILURIAN

ORDOVICIAN

CAMBRIAN

580

488

444

416

318

299

200

146

Million years ago

NY RockRecord

PENNSYLVANIAN

HOLOCENE

65.5

251

1.85.3

0.010

23.033.9

MISSISSIPPIAN

Humans, mastodonts, mammoths

55.8

Large carnivorous mammalsAbundant grazing mammalsEarliest grasses

Many modern groups of mammalsMass extinction of dinosaurs, ammonoids, and many land plants

Earliest flowering plantsDiverse bony fishes

Earliest birds

Earliest mammals

Mass extinction of many land and marine organisms (including trilobites)

Mammal-like reptiles

Abundant reptiles

Extensive coal-forming forests

Abundant amphibiansLarge and numerous scale trees and seed ferns (vascular plants); earliest reptiles

359Earliest amphibians and plant seedsExtinction of many marine organisms

Earth’s first forestsEarliest ammonoids and sharksAbundant fish

Earliest insectsEarliest land plants and animals

Abundant eurypterids

Invertebrates dominantEarth’s first coral reefs

Burgess shale fauna (diverse soft-bodied organisms)Earliest fishes

Earliest trilobites542

Abundant stromatolites

Ediacaran fauna (first multicellular, soft-bodied marine organisms)

Extinction of many primitive marine organisms

First sexually reproducingorganisms

Oldest known rocks

Estimated time of originof Earth and solar system

Sediment

Bedrock

Abundant dinosaurs and ammonoids

Earliest dinosaurs

Great diversity of life-forms with shelly parts

1300

Evidence of biologicalcarbon

Earliest stromatolitesOldest microfossils

Oceanic oxygenproduced bycyanobacteriacombines withiron, formingiron oxide layerson ocean floor

Oceanic oxygen begins to enterthe atmosphere

Geologic Time Scale Start Here: Examine the geologic timeline of our planet.

Today, you will be investigating how current conditions on Earth are the result of our planet and its life forms evolving simultaneously over long stretches of time.

Formation of Earth Meteorites (samples #1-3): How old are they?

Four Density Blocks (#4–7): Lift the four blocks and compare their weights. Which is lightest? Heaviest? What can they tell us about the layers of Earth? What does this tell us about the way they formed?

The Oldest Known Rocks (#12): How old is it?

What does it contain and what does it tell scientists about early Earth?

Life in Early Earth Sulfide Chimneys (#26–30): Where are hydrothermal vents found, and how do they form? When did they form? Why do scientists think that life began at vents like these?

Gottesman Hall of Planet Earth Grades 9-12

Student Worksheet: Investigate Geologic Time

© 2012 American Museum of Natural History. All rights reserved.

(Answers may include: #7, which represents water, is the lightest. #4 iron, which represents the core, is the

heaviest. As Earth started to grow, heavier materials sank to the center to form the core and lighter elements were

driven from the interior to form an ocean and atmosphere.)

(Answers may include: By dating the zircons embedded within the Acasta gneiss, geologists have determined its

age to be 3.96 billion years. The rock’s composition establishes it as part of a continent, indicating that continents

existed nearly 4 billion years ago.)

(Answers may include: They form when metals from underwater hot springs react with seawater to precipitate

as sulfide minerals. Scientists theorize that some of the first forms of life may have emerged around volcanic

vents along the ocean floor, and these microbes flourished in the absence of sunlight by getting energy from the

chemical compounds billowing out of these vents.)

1

23

4

56789

10

1

2

3

4

5

(Answer: between 4.5 and 4.6 billion years old)

(Answer: 3.96 billion years old)

1997

ANSWER KEY

Concentration of iron in the ocean

Concentration of oxygen in the atmosphere

stromatolitesiron + oxygen

black smoker

iron

oxygen

formation of Earth

4.6 billion years ago 3.8 bya 2.6 bya

firstmicrofossils

560 mya 250

today

banded iron formation

first evidence of life

BANDED IRON FORMATIONS

Stromatolite (#14): How old is it?

What are stromatolites and what can they tell us about the early Earth?

Banded Iron (#15): How old is it?

Examine the “How do we know about the early atmosphere?” diagram. Label it to show how oxygen and iron composition changed over time.

The Oldest Fossil? (#16): Watch the video above about the evolution of microfossils and examine the fossil specimen. How old is it?

Pyrite-Bearing Conglomerate (#17), Gray-White Quartzite (#18), and Red Quartzite (#19): Compare the color and composition of the three samples. What type of rocks do you think they are? What can the color variations and composition of the Huronian Supergroup tell us about how the atmosphere has changed over time?

Glaciation Earliest Ice Ages (#20), Debris from Oldest Glaciers (#21), and Outcrop of Glacial Sediments (#22): How old are they?

How do these samples provide evidence of an early ice age?

Gottesman Hall of Planet Earth Grades 9-12

© 2012 American Museum of Natural History. All rights reserved.

(Answers may include: These are sedimentary rocks. They record the rise of an oxygen

atmosphere produced by photosynthetic organisms like the stromatolites. The oldest rocks are grey because

there was no oxygen to cause them to rust. The youngest rocks are red because as oxygen became more

abundant, the iron could then react with oxygen and turn red.)

(Answers may include: When rock fragments do not touch, it indicates that they were carried and deposited by

melting glaciers.)

(Answers may include: Stromatolites are bacteria mats that formed into colonies in shallow oceans. They tell us

that life most likely began in the oceans and could only live in shallow water.)

ANSWER KEY6

7

8

9

(Answer: 900 million years old)

(Answer: 2.736–2.687 billion years old)

(Answer: 3.5 billion years old)

10(Answer: 2.3 billion years old)

Physical Setting/Earth Science Reference Tables — 2011 Edition 8

PLEISTOCENEPLIOCENE

MIOCENE

OLIGOCENE

EOCENE

PALEOCENE

LATE

EARLY

LATEMIDDLE

EARLY

LATE

MIDDLEEARLYLATE

MIDDLE

EARLY

LATE

MIDDLE

EARLY

LATE

MIDDLE

EARLY

LATE

EARLY

LATE

MIDDLE

EARLY

LATE

MIDDLE

EARLY

EARLY

LATE

GEOLOGIC HISTORY

ElliptocephalaCryptolithus

Phacops Hexameroceras ManticocerasEucalyptocrinus

CtenocrinusTetragraptus

Dicellograptus EurypterusStylonurus

B LA EC D G HF I J NK M

CentrocerasValcouroceras Coelophysis

(Index fossils not drawn to scale)

EraEonP

HA

NE

RO

-Z

OIC

PR

EC

AM

BR

IA

NA

RC

HE

AN

PR

OT

ER

OZ

OI

C

LATE

LATE

MIDDLE

MIDDLE

EARLY

EARLY

0

500

1000

2000

3000

4000

4600

Million years ago

CENOZOIC

MESOZOIC

PALEOZOIC

QUATERNARY

NEOGENE

PALEOGENE

CRETACEOUS

JURASSIC

TRIASSIC

PERMIAN

CA

RB

ON

IF-

ER

OU

S

DEVONIAN

Period Epoch Life on Earth

SILURIAN

ORDOVICIAN

CAMBRIAN

580

488

444

416

318

299

200

146

Million years ago

NY RockRecord

PENNSYLVANIAN

HOLOCENE

65.5

251

1.85.3

0.010

23.033.9

MISSISSIPPIAN

Humans, mastodonts, mammoths

55.8

Large carnivorous mammalsAbundant grazing mammalsEarliest grasses

Many modern groups of mammalsMass extinction of dinosaurs, ammonoids, and many land plants

Earliest flowering plantsDiverse bony fishes

Earliest birds

Earliest mammals

Mass extinction of many land and marine organisms (including trilobites)

Mammal-like reptiles

Abundant reptiles

Extensive coal-forming forests

Abundant amphibiansLarge and numerous scale trees and seed ferns (vascular plants); earliest reptiles

359Earliest amphibians and plant seedsExtinction of many marine organisms

Earth’s first forestsEarliest ammonoids and sharksAbundant fish

Earliest insectsEarliest land plants and animals

Abundant eurypterids

Invertebrates dominantEarth’s first coral reefs

Burgess shale fauna (diverse soft-bodied organisms)Earliest fishes

Earliest trilobites542

Abundant stromatolites

Ediacaran fauna (first multicellular, soft-bodied marine organisms)

Extinction of many primitive marine organisms

First sexually reproducingorganisms

Oldest known rocks

Estimated time of originof Earth and solar system

Sediment

Bedrock

Abundant dinosaurs and ammonoids

Earliest dinosaurs

Great diversity of life-forms with shelly parts

1300

Evidence of biologicalcarbon

Earliest stromatolitesOldest microfossils

Oceanic oxygenproduced bycyanobacteriacombines withiron, formingiron oxide layerson ocean floor

Oceanic oxygen begins to enterthe atmosphere

ANSWER KEY

5

8

4

2

6

7

10

SulfideChimneys

Stroma- tolite

Early Ice Age

BandedIron

OldestFossil

OldestKnownRocks

Meteor-ites