WEBQUEST 4-30
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?
1ST PERIOD WEBQUEST
3RD PERIOD WEBQUEST
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.
New Dinosaur Finds In Antarctica Paint Fuller Picture of Past Ecosystem. Visit this site to learn why the discovery of a hadrosaur, a duck-billed dinosaur, in Antarctica is an important clue to the climate of the continent 66 to 67 million years ago.
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.
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.
posted by Mr. Gibney @ 6:13 PM
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