Key Question
What evidence do we
have that over time
continents can move?
Learning Goals
• solve a puzzle to construct Pangaea,
• use a map to identify present day
continents on Pangaea, and
• read and explain what evidence
Wegener used for his theory.
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North
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South
America
Antarctica
Africa
India
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Greenland
Eurasia
Australia
© 2007 AIMS Education Foundation
Number the continents/countries.
1. Australia
2. India
3. Antarctica
4. Africa
5. Eurasia
6. South America
7. North America
8. Greenland
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Cynognathus
South America
Mesosaurus
Africa
Glossopteris
Lystrosaurus
Antarctica
India
Australia
Fossil Record
2
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Alfred Wegener was born in Germany. He
earned a doctorate degree in astronomy
from the University of Berlin. However,
his interests were redirected to the study
of weather and climate.
There were many things that
Wegener could not explain with this
theory. For one, he did not know
what allowed the continents to drift.
Wegener died while on a climatological
expedition in Greenland. Scientists
and historians marvel at how Wegener
used information from climatology,
paleontology, and geology to
develop his theory. Today,
scientists accept parts
of the continental
drift theory while
rejecting other parts.
That theory led to
the later theory of plate
tectonics.
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One method used to study climates of
the past is to look at the fossil record
to determine what conditions existed
when the fossilized organisms lived.
As Wegener was browsing through
scientific papers that listed fossils, he
discovered that identical plants and
animals were found on both sides of
the Atlantic Ocean. This piqued his
interest.
In 1915, he published a book called
The Origins of Continents and Oceans.
He explained that at one time Earth’s
landmasses created a supercontinent
that he called Pangaea. He explained that
the supercontinent broke up into smaller
continents that drifted apart. Wegener’s
theory was called continental drift.
As he pondered this, he put the fossil
information together with his observation
that the Atlantic coasts of South America
and Africa appeared to fit together. He
wondered if the continents had been
joined together at one time. Wegener
began to look for supporting evidence for
this idea.
In his research, Wegener found glacial
deposits in southern Africa, South
America, India, and Australia. He
knew that these areas were tropical
and subtropical. How could they have
been covered with ice? He used this
evidence to show that the location
of the continents today was not the
same as in the past. By examining the
glacial markings left on rocks, he tried
to determine how the continents had
moved.
He found similar geologic structures on
South America, Africa, and Antarctica.
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Connecting Learning
1. What evidence did Wagner
use to propose the theory of
continental drift?
2. How did your group decide on how to
arrange the puzzle pieces?
3. How did the second map help you
decide where some of the present
day continents were on Pangaea?
4. What did the location of the fossils
tell Wegener?
5. Continental drift and plate tectonics
are theories. How is a theory different
from a fact or law?
6. What are you wondering now?
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