Name: ___________________________________ Period: ________________________ Student Exploration: Building Pangaea Vocabulary: continental drift, fossil, glacier, ice age, landmass, Pangaea, supercontinent Prior Knowledge Questions 1. Antarctica is a frozen land, so cold and icy that no trees can grow there. Yet scientists have discovered fossils (remains preserved in rock) of ancient trees in Antarctica. What do you think this means? I think this means it was warm there before. 2. The Himalayas in central Asia are the tallest mountains in the world. But fossils of seashells can be found high in these mountains, far from any ocean. How do you think they got there? I think that the seashells got there because the Himalayas were one underwater. Gizmo Warm-up 1. The Gizmo allows you to drag and rotate all the major landmasses on Earth.  To drag a landmass, grab it in the middle.  To rotate a landmass, grab it near the edge.  Learn the names by opening the Tools menu and dragging the Help icon over the landmasses.  Mark where you live. Open the Tools menu and drag an arrow to your location. 2. Test your geography skills. Drag and rotate landmasses randomly until you make a big mess. Then try to move them back to their original positions. When you have made the best map you can, open the Tools menu, select Screen shot, and copy the image into a blank document. Label the image “Map 1.” 3. Click Reset. Compare your map to the real one. How well did you do? Get the Gizmo ready: Activity A:  If necessary, click Reset. Solving the puzzle  Check that the Evidence shown is None. Introduction: In 1915, a German scientist named Alfred Wegener (VAY-guh-ner) proposed the theory of continental drift. According to this theory, the landmasses once were joined into a supercontinent called Pangaea. The landmasses then slowly drifted to their current positions. Question: What did Pangaea look like? 1. Observe: Drag South America close to Africa. Look at their coastlines. What do you notice? I noticed that they match. 2. Explore: Try to fit all the landmasses together like a puzzle.  As much as possible, avoid overlapping landmasses.  When you are satisfied, take a screenshot and paste it into your document. Label this map “Map 2: Fit of the continents.” 3. Analyze: Look at your map of Pangaea. A. How well do the continents fit together? Some fit fine but not all. B. Is it a perfect fit? Explain? It’s not a perfect because over time the land changed and got weathered at the coast. C. Think about how the landmasses got from where they were to where they are today. Does it seem realistic that the landmasses could have moved like this? Explain. Yes: It is realistic that the landmasses could have moved like this because I already that continents move because of convection currents and even though it takes them a long time to move it has been 335 million years since Pangea has been a super continent so that is why I believe it is possible that the landmasses moved like that. 4. Compare: If possible, present your map of Pangaea to your classmates and teacher. Look at other maps, and talk about each one. A. Are the maps very similar or very different? Very Different B. If Alfred Wegener showed you a map like this but did not have any other evidence, would you have believed his theory that the continents had moved? Explain. No because it would seem like a bunch of nonsense because if there is no evidence to back up his claim it would be hard to trust a random man. Activity B: Get the Gizmo ready: Fossil and rock evidence  Click Reset.  Under Evidence choose Fossils. Question: What do fossils and rocks tell us about Pangaea? 1. Observe: The brown areas in the Gizmo show where fossils of Lystrosaurus have been found. Lystrosaurus looked a bit like a dinosaur, but lived in a time before dinosaurs. A. On which landmasses did Lystrosaurus live? Lystrosaurus lived in Africa, India, and Antarctica B. Lystrosaurus probably couldn’t swim very far. How might the locations of Lystrosaurus fossils be seen as evidence that the continents were once together? The location of their fossils can be seen as evidence because if they were found at a different continent then where they are usually supposed to be than that means that they walked over to a different continent, and they can’t swim so Pangea existing would be the most reasonable explanation. 2. Explore: Use the fossil evidence to help you make a new map of Pangaea. When the map is done, paste a screenshot into your document. Label this map “Map 3: Fossil evidence.” How well do the landmasses fit together this time? Perfect 3. Revise: Now under Evidence choose Rocks. The purple areas are mountains that formed when landmasses collided 450 million years ago. The orange areas show rocks that formed about 2 billion years ago. Adjust your map using this evidence, and then paste a screenshot of this map into your document. Label this map “Map 4: Rock evidence.” 4. Compare: If possible, compare your map to those of your classmates. A. How similar are the maps? _____________________________________________ B. If Wegener showed you this evidence, would you have believed his theory? Explain. ___________________________________________________________________ ___________________________________________________________________ 5. Extend your thinking: Click Reset and watch India closely. The Himalayan Mountains are found on the border of India and Eurasia. How do you think these mountains were formed? The Himalayas were formed when the Indian Plate and the Eurasian Plate collided. Activity C: Ancient ice sheets Get the Gizmo ready:  Click Reset.  Under Evidence choose Glaciers. Introduction: Glaciers are large, slow-moving sheets of ice. During ice ages, glaciers formed at the North and South Poles and spread out to cover large areas. Question: What does evidence of glaciers tell us about Pangaea? 1. Observe: The white areas are places that show evidence of a massive ice sheet that existed around 250 million years ago. A. Which landmasses show evidence of ancient glaciers? South America, Africa, Madagascar, India, Australia and Antarctica. B. Would you expect to find large glaciers on all of these landmasses today? Explain. No because the ice age is over. But only in Antarctica 2. Explore: Drag the landmasses together to form a map of Pangaea. Try to line up the white areas on each continent. You can use the fossil and rock evidence as well if you like. Paste a screenshot of this map into your document, labeled “Map 5: Glacial evidence.” 3. Analyze: Choose Glaciers (if necessary) and look at the white regions. Does this pattern make more sense now? Explain. Yes this pattern makes more sense now because it seems like the coldness of Antarctica spread across to other areas. 4. Extend your thinking: As glaciers moved away from the poles, rocks stuck to the bottom of the ice were dragged over the ground. This left scrapes and scratches on rock outcrops that can still be seen today. The scratches show which direction the glaciers moved. A. Look at the arrows that show the direction of glacial scratches. What is the pattern? The pattern is a circle spreading from the center which would be Antarctica. B. Which landmass do you think was located over the South Pole in the time of Pangaea? Why? Discuss your answer with your teacher and classmates. I think the land mass South America, Africa, Madagascar, India, Australia, and Antarctica were over the south pole.