PBS
Pbs Learning Media: The Grand Canyon: Evidence of Earth's Past
In this video segment adapted from NOVA, a fossil found among the Grand Canyon's rock layers reveals the existence of a shallow sea that once covered most of western North America.
PBS
Pbs Learning Media: The Grand Canyon: The Top Two Rock Layers
This brief video segment adapted from NOVA uses illustrations and the well-preserved footprints of a small reptile to portray the history of the Grand Canyon's top two rock layers.