what are the animals that live underground?
['Olm. Also known as the proteus, the olm is a sea-dwelling creature. ... ', 'Earthworm. Earthworms are classified as being underground living animals because of their ability to exist in land soils. ... ', 'Cave Beetle. ... ', 'Armadillo. ... ', 'Mole. ... ', 'Bilby. ... ', 'Chipmunk. ... ', 'Badger.']