The male equivalent of the mermaid is the merman, also a familiar figure in folklore and heraldry. Although traditions about and sightings of mermen are less common than those of mermaids, they are generally assumed to co-exist with their female counterparts.
Some of the attributes of mermaids may have been influenced by the Sirens of Greek mythology. Historical accounts of mermaids, such as those reported by Christopher Columbus during his exploration of the Caribbean, may have been inspired by manatees and similar aquatic mammals. While there is no evidence that mermaids exist outside of folklore, reports of mermaid sightings continue to the present day, including 21st century examples from Israel and Zimbabwe.