![]() ![]() Tim puts his head against the ground, trying the notice the ground moving. ![]() ![]() TIM: Well, when the continental plates shift, you hardly ever notice the gound moving continents only move about a few centimeters every year! This motion explains why fossils of the same kinds of prehistoric animals were found on the northeast coast of South America and the southwest coast of Africa.įossil pictures are placed on northeastern South America and southwestern Africa. TIM: When the plates move, continents shift along with them in a process called continental drift. The outside layer is labled "crust" and the layer under it is labled "mantle." These plates float around on a layer of molden rock called the outer mantle.Īn image shows a picture of the Earth, then it shows the inside layers of the Earth. TIM: Now, it's not like they were floating, the ocean floor was moving too! The outer layer of the Earth, or crust, is broken up into about a dozen major, and many minor, tectonic plates. The continents assume the shapes we know today. Then it shows Pangaea breaking into several pieces which drift apart from one another. Scientists believe Pangaea existed about 2 or 300 million years ago, then it started to break apart, eventually forming the continents we know today.Īn image shows a world map with a single, huge continent. TIM: This supports the theory that all of continents were once one big continent called Pangaea. The continents Africa and South Americas pop up and press each other. TIM: If you look at the shapes of Earth's continents, Africa and South America look like pieces of a puzzle that could snap together.Īn animated map shows the Earth's continents. TIM: Sounds like we need to get into the theory of plate tectonics! Tim, and his robot friend Moby, are standing in a desert. What in the world is a "Pangaea"? Signed, DAN (via the Internet) Text reads: "The Mysteries of Life with Tim and Moby." ![]()
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