Manatees, also known as sea cows, belong to the scientific Order Sirenia. They are the only herbivorous marine mammals, subsisting entirely on seagrasses and other aquatic vegetation. They have an extremely low metabolism and zero tolerance for cold water. Although scientists often lump Sirenians together with the order Cetacea (whales and dolphins) as totally aquatic marine mammals, the closest modern relative of the manatee (and its Australian counterpart the dugong), is the elephant.

Sirenia comes from the word siren. In ancient Greek mythology, sea nymphs called sirens used their mesmerizing song to lure mariners to shipwreck and destruction. The first recorded observations of manatees date back to Columbus' expedition in 1492. It is now thought that early reports of mermaids were actually sightings of manatees (or their relatives). The legend of the mermaid may have originated with these gentle creatures. After long months at sea, sailors may have caught fleeting glimpses of these large, affectionate sea creatures, mistaking them for beautiful, be-flippered mer-women.