Animals that live underground include earthworms, moles, blind salamanders, groundhogs, aardvarks and ants. Some underground animals regularly come to the surface in search of food and nest materials. Others remain underground unless circumstances force them to relocate.
Animals that live underground have evolutionary adaptations that help them thrive in dark low-oxygen subterranean environments. For example, snakes and worms have smooth cylindrical bodies conducive to traveling through tunnels. Moles are also cylindrical, and their powerful front paws have long talons designed for digging through soil and gravel. Their short, soft coat has no natural nap, which allows the moles to crawl forward and backward with equal comfort.
Like moles, kangaroo rats create large underground burrows in which they spend most of their time. Unlike moles, however, these rats surface regularly in search of food. Once sated, these desert dwellers return to their burrows. Kangaroo rat burrows protect the rats from predators and from the harsh desert heat. During the day, kangaroo rats plug the entrances to their burrows with mounds of dirt. This keeps the interior comfortably cool.
Underground environments receive little or no light. Animal species that have adapted to life in total darkness have little need for eyes. Some have small eyes and poor vision, while others have no eyes at all. These creatures navigate, find prey and avoid danger through acute hearing and a remarkable ability to sense vibrations. For example, moles immediately sense the presence and precise location of earthworms that enter the tunnels.