Two hundred million years ago, all of the continents on
Earth were joined in one large supercontinent scientists
call Pangaea. The formation of Pangaea dried up many shallow
seas, which led to the evolution of new species on land.
This is the time during which mammals first began to appear.
During the Mesozoic Era, around 190 million years ago,
Pangaea began to break up. The breakup resulted in two
landmasses: Laurasia, the northern group of continents, and
Gondwanaland, the southern group of continents. Gondwanaland
included South America, Antarctica, Australia, Africa, and
India. By the end of the Cretaceous Period 65 million years
ago, Africa and South America had moved apart. By 43 million
years ago, Australia and Antarctica had separated and moved
to their present locations.
How do we know that these events actually happened? You
have probably noticed that South America and Africa seem
to fit together like puzzle pieces. Because of this fit,
many people wondered if the continents once were joined.
A German scientist named Alfred Wegener proposed that all
of the continents once had been joined in a supercontinent
that he called Pangaea. He suggested that Pangaea began
to break apart millions of years ago, and that the continents
continued to move until they reached their present locations.
He called his hypothesis continental drift. Today,
Wegener’s hypothesis is known as the theory of plate
tectonics. Wegener was the first scientist to base his hypothesis
on more than the fit of the continents. He collected data
on rock formations, fossils, and climates to support his
hypothesis. Wegener found the same rock formations and fossils
in Africa, South America, and Antarctica. Some of the fossils
were of species that grew in only one type of climate, yet
the fossils were found on continents with differing climates.
How could there be fossils of tropical and temperate climate
species in Antarctica, a continent that is permanently covered
with ice and snow? Have any fossils been found in Antarctica
that can support Wegener’s hypothesis, and thus, the
theory of plate tectonics?
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Your job in this WebQuest is to discover what fossils have
been found in Antarctica, and to identify how those fossils
either support or disprove Wegener’s hypothesis and
the theory of plate tectonics. You will have to find out
what kinds of fossils have been found in Antarctica. You
will have to discover how to interpret the meaning of these
fossils as indicators of the climate that once prevailed
in Antarctica. Finally, you will answer a set of questions
about the fossils of Antarctica to demonstrate what you
have learned.
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Look at the web sites given here to find the information
that will enable you to answer questions about Antarctica
fossils.
- Marine
Fossils from Antarctica. Visit this site for an
overview of the fossils found in Antarctica and what they
reveal about the past climate and geographical location of
Antarctica. Scroll down to see photographs of some of the
fossils found on Vega Island, an island just off the coast
of Antarctica.
- Antarctic
Dinosaurs. At this site you can learn more
about the first dinosaur fossils found in Antarctica,
including a Late Cretaceous ankylosaur found on James Ross
Island in 1986. Scroll down to find out why so few
dinosaur fossils have been found on this continent.
- Fossils
From Mesozoic Era Antarctica. Go to this site for
a brief discussion of continental drift (now called plate
tectonics) and how it affected Antarctica. There is a good
map of Antarctica here. Scroll down to see an interactive
graphic of continental drift with a key to the continents.
Continue to scroll down to see a list of fossils found in
Antarctica.
- When
Dinosaurs Roamed Antarctica. Visit this site to
read about dinosaur and reptile fossils found in the
Transantarctic Mountains. These fossils are from the
middle Jurassic, about 175 million years ago.
- The
Lost World Discovered? At this site you can
read an overview of the fossils found in Antarctica from
the first expeditions to the present. This site includes a
short history of human presence on Antarctica as well.
- Secrets
of the Ice: Antarctica in the Past. Visit this
site to learn about the geologic history of Antarctica.
Scroll down to see an interactive graphic of the breakup
of Gondwanaland and the subsequent movement of Antarctica
to its present location.
- Antarctic
Summer - Fossils in Antarctica This report by ABC
News Online discusses the issues surrounding fossils that
were found in Antarctica in 1978. Read the report to learn
what types of fossils were found and what is being done to
preserve the exposed fossils that still exist.
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1 class period for Internet research and answering the
set of questions
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Read through the following set of questions before you
begin your Internet research. As you explore each site, look
for answers to the questions.
Questions about the Fossils of
Antarctica
- What were the first fossils found in Antarctica? Where
and when were they found?
- What was the first dinosaur fossil found in
Antarctica? Where and when was it found?
- What dinosaur fossil was found on Vega Island in 1986?
- What are the two reasons the fossil found on Vega
Island is of particular importance to understanding the
climate and location of Antarctica millions of years ago?
- The first dinosaur fossil and the fossil found on Vega
Island in 1986 were representative of what geologic time
period?
- What dinosaur fossil was found in the Transantarctic
Mountains in the summer of 1990-1991? During what geologic
time period did this dinosaur live?
- Besides the fossils already discussed, name the other
fossil animals that have been found in Antarctica.
- Why have so few dinosaur fossils been found in
Antarctica?
- Early expeditions to Antarctica reported on seeing
fossils, but they did not collect them. Who first reported
seeing fossils of leaves and stems of plants? Who reported
finding beds of coal near the South Pole?
- How do plant fossils and beds of coal support the idea
that Antarctica once was warmer than it is today?
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In the process of completing this WebQuest, you’ve
become informed about the fossils found in Antarctica, and
what those fossils tell us about the climate and location
of Antarctica millions of years ago. You have learned that
some dinosaur fossils found in Antarctica were previously
found only in the Americas. You have discovered that some
Antarctica fossils were of species that could live only
in temperate or tropical climates. You have developed research
skills as you explored the web sites given and identified
the relevant information to answer the set of questions
above. Do you agree with Wegener that Antarctica must have
had a warmer climate millions of years ago? Do you think
that the information you have gathered about Antarctic fossils
supports the theory of plate tectonics?
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