Flashlights and remote controlled cars get their energy from batteries. Plants and animals get their energy from the sun. Plants use the direct light energy from the sun to grow. Animals use the sun's energy indirectly by eating plants or by eating another animal that eats plants. Scientists have found two basic kinds of animals that live in caves, animals that are in the cave all the time and animals that use the cave only as a shelter and go outside to eat.
Bats are a good example of animals who sleep in caves but hunt for food outside.
Animals that live in a cave all the time like salamanders or cave fish have to get their food energy from things brought in from the outside world. Caves act like natural drain pipes by allowing water to flow in and out of them. Often rain water washes in leaves and bits of wood into a cave system. Guano is another type of Organic Debris found in caves and it makes a good garden fertilizer. These Molds are then eaten by animals like salamanders and crickets.