Caves are dark hollow spaces in the ground or can be a wide open space in a mountain. Caves are dark except when you are in the entrance zone. The entrance zone is usually the same temperature as outside the cave. The twilight zone is a little colder and the dark zone is a cold temperature.

Caves can be found all over the United States. All kinds of caves can be found in Mexico. Four types of caves are glaciers, lavas, dry caves, and sea caves.

Plants that live in caves are mosses, marsh, ferns, and liverworts.

The animals that live in the caves are cave crickets, millipedes, salamanders, spiders, beetles, daddy longlegs, blind flat worms, bats, and crayfish.

One animal to animal interaction is when bats poop the insects eat it and get nutrients to live.

Interesting facts about caves are there are three different parts of a cave, the entrance zone, the twilight zone, and the dark zone. Dry caves are made by wind blowing sand and stones against the soft rock of cliffs.