Evidence That Plates Move: Fossils, Rocks and Fitting Continents (Grade 6 to 8 Science)

Hi, I'm Luna from DoodleBeez. Earth's surface is broken into giant pieces called plates, and they move a few centimeters each year. But how do scientists know? Today we will look at the evidence like detectives.

Clue one. The continents fit together like puzzle pieces. Look at a map, and the east coast of South America matches the west coast of Africa. Alfred Wegener noticed this over one hundred years ago.

Clue two. Fossils of the same ancient species appear on continents now separated by oceans. Mesosaurus, a small freshwater reptile, is found in both South America and Africa. It could not have swum across an ocean.

Clue three. Matching rock layers and mountain chains line up across oceans. The Appalachian Mountains in North America match old mountains in Scotland and Scandinavia.

Clue four. Ancient climate evidence. Scientists find signs of glaciers in places that are hot today, like India and Africa, and coal from tropical forests in Antarctica. Those lands must have moved.

Clue five came from the ocean floor. Scientists found that new rock forms at mid ocean ridges and spreads outward. Rocks get older the farther they are from the ridge, like a slow conveyor belt.

Now it's your turn. Fossils of the same land plant, Glossopteris, are found in India, Africa, Australia and Antarctica. What does this suggest? Pause and try. These continents were once joined together.

Great job! Remember, fitting coastlines, matching fossils, lined up rocks, ancient climates and seafloor spreading all show that plates move. Practice evidence plates move in the Science Lab at doodlebeez.com. See you next time!