Earth has been around for about 4.6 billion years, and the planet has been through all kinds of changes during that time, from hellish oceans of magma to a frozen coating of glaciers to diverse ecosystems filled with life. Geologists can read the planet's history by looking at distinct signatures in its rock layers, and they mark each chapter with a meaningful title: Cambrian, Jurassic, Holocene, Pleistocene, just to name a few.

Today, scientists argue that we have started a new chapter in the story of Earth: the Anthropocene, and for the first time in the planet's history, one species is its primary author.

The animation above explains what scientists mean when they talk about the Anthropocene and why our actions in this "age of humans" matter for everyone's future.