Did you know? Prairie dogs are named for their habitat and warning calls, which sound similar to a dog's bark. [VID: Compilation footage of prairie dogs] | Nature | PBS

Prairie dogs live in huge, underground networks called "towns." [VID: Did you know? Prairie dogs live in "towns." Towns are huge, underground burrows, found in the prairies and plateaus of North America. Undisturbed towns have tens of thousands of prairie dog residents and go for miles in every direction. In 1900, a prairie dog town the size of Maryland was discovered in Texas. Its tunnels were home to an estimated 400 million prairie dogs.] | Nature | PBS