Plate Tectonics Engine

Earth is the only known planet with active plate tectonics — interlocking lithospheric plates, made of crust plus uppermost mantle, that slide, collide, and separate over millions of years. This recycles carbon through the rock cycle, regulating atmospheric CO2 and keeping temperatures stable. The same engine:

• Builds mountains and drives volcanic activity
• Creates the geological diversity that supports countless ecosystems
• Keeps CO2 in check, so the planet avoids a runaway greenhouse like Venus

Earth's interior heat makes it a living planet in every geological sense.