What makes caves?
• Name some famous caves you have visited. • Discuss what the class knows about caves. • From the discussion, write a definition of caves that the class agrees upon. (Explain to younger children what a “definition” is.) • The class definition should include the following points: A cave is: • A hole, tunnel, or series of branching openings. These are often called caverns or rooms. • Underground or underwater, mostly in darkness. • Usually formed in rocks called limestone, marble, or lava. • Usually created by water dissolving limestone (over periods of thousands of years). Rivers and streams sometimes go underground as part of their course. Then, they are called “sinking streams.” • Often the site of unusual rocks (stalagmites, stalactites, flowstone) formed by water dripping onto or flowing through a cave. • Often home to people and animals, including some animals that can live without light (bats, crickets, blind fish). • Often very large. (One cavern in Carlsbad Cavern, New Mexico, i
