I thought the idea mermaid came from sailors hallucinating from being at sea for months on end and fucking dolphins or something >_>
Hm, not really. Mermaids were originally the sirens of Greek mythology. They were depicted as half-bird, half women type creatures. Over time and maybe during the Hellenistic Period (323 BC - 31 BC), the sirens gradually shifted into half fish, half women type creatures.
In a naturalist theory, the idea of mermaids came from mistaken sightings of manatees and dugongs by men at sea.
---His foundation lie in the holy mountain. Selah.