Terrestrial animals are animals that live predominantly or entirely on land (e.g., cats, ants, emus), as compared with aquatic animals, which live predominantly or entirely in the water (e.g., fish, lobsters, octopuses), or amphibians, which rely on a combination of aquatic and terrestrial habitats (e.g., frogs). The term terrestrial is also frequently used for species that live primarily on the ground, in contrast to arboreal species, which live primarily in trees.