Geologic Time Scale

Geologic Time Scale

The geologic time scale is a system scientists use to describe the history of the Earth. It organizes Earth's 4.6-billion-year history into different periods based on major events like the formation of the planet, the appearance of life, mass extinctions, and the rise of new l...

The geologic time scale is a giant timeline that organizes major events such as the evolution of life, climate changes, and mass extinctions.

Life on Earth started with tiny, simple, single-celled organisms. Over billions of years, they evolved into protists, fungi, plants, and animals.

The evidence for this transformation is found...