Did Earth’s tectonic plates spark life—and could they hold the key to alien life?

Earth’s surface is a dynamic, ever-changing landscape. Massive crustal plates shift, creating mountains, earthquakes, and volcanic activity. This process, known as plate tectonics, may be the very reason life thrives on Earth. Uniquely, Earth is the only planet known to have both plate tectonics and life, a coincidence that many scientists believe is meaningful.

Through tectonic movements, Earth’s plates pull carbon from the atmosphere into the mantle, stabilizing the climate. They also push life-supporting minerals toward the surface, fostering ecosystems that span from ocean depths to mountain peaks. However, while scientists generally agree on the benefits of plate tectonics, they are less certain about when this process began or how essential it was to life’s origins. Some propose that plate tectonics started around 700 million years ago, while others suggest an even earlier origin, possibly billions of years before multicellular life appeared.

Research into ancient rock chemistry offers clues. Studies indicate that around 3 billion years ago, Earth’s crust began to melt and reform, a potential sign of tectonic activity. Some evidence hints that tectonics might have started during the Hadean eon over 4 billion years ago, suggesting that early life may have evolved on an already tectonically active planet.

Plate tectonics not only shapes the environment but may also fuel life’s evolution by creating diverse habitats and encouraging adaptation. Even following mass extinctions, tectonic activity enables life to rebound by stabilizing atmospheric conditions and recycling vital minerals back into the biosphere. These aspects lead scientists to wonder if tectonics could be an essential ingredient in the search for life on other planets.