PBS
A Brief History of Geologic Time
How do scientists know the history of Earth before humans—or any mammals—existed? An epic "Eons" series video explains the larger history of geologic time. It highlights the eons, eras, periods, epochs, and ages scientists use to divide...
Be Smart
The Impossible Hugeness of Deep Time
Can we really grasp how old we are? Part of a larger series, the humorous video demonstration shows how humans fit into the history of Earth and just how long ago life formed. Viewers explore a timeline that identifies major markers in...