Legendary humanlike sea-dwelling mammals. Most reports of mermaids can be traced to one of two sources: legends represented by the stories of the ancient Roman writer Pliny The Elder and the tales of the selkies, or seal-people of northern Europe; or mistaken identity, in which sailors confused dugongs, manatees, or other sea mammals for mermaids. In addition some mermaids are frauds. Fishermen, especially in Japan during the 19th century, learned to create artificial mermaids by sewing fish tails to the upper torsos of monkeys. Yet, despite these frauds, people continue to report seeing mermaids and mermen. As recently as August 1949, fishermen off the coast of Scotland claimed to have seen merfolk at a distance.
In some cases, the being in question is unmistakably a manatee or dugong. Christopher Columbus reported seeing mermaids during his voyages of discovery in the late 15th century, but he concluded that “they are not so fair as they are painted.” In 1927 the British naturalist W. P. Pycraft identified a mermaid sighting in the Red Sea as a dugong. In the mid-20th century reports of a ri, a mermaidlike animal, off the coast of Papua New Guinea brought about an expedition by U.S. cryptozoologists; through underwater photography, they discovered that the animal was in fact a dugong.