Tectonic Plates’ Patterns Revealed

The biggest jigsaw puzzle in the solar system has a split personality: The number and sizes of Earth's tectonic plates can flip, according to a new study.

Today, the pieces of Earth's broken shell are unequal in size. Of about 50 plates, a mere seven account for 94 percent of the surface. The biggest, the Africa and the Pacific plates, are antipodal, meaning they sit on opposite sides of the Earth.

But about 100 million years ago, the tectonic plates tiled the planet as evenly as a real-life jigsaw puzzle.  LiveScience