"They swim about, bothering nobody, bothered themselves only by their own loneliness. Often these creatures want to get married, you see. To people who don't have fins."
IF YOU want to believe in mermaids (or mermen or merfolk of any kind, for that matter) then the Igpupiara are a pretty good place to start. As long ago as 1585 Father Fernao Cardim wrote about them in a treatise on the people and places of Brazil, although even he wasn't the first to do so. The mermaids he heard about were not cute, passive beings. While the females were said to be beautiful, with long flowing hair, they were apt to squeeze a man to death, and they didn't stop there. Once their prey was dead they would pluck out his eyes and eat them; bite off his nosetip, tips of fingers and toes; and also make feast of his genitals. Corpses thus mutilated were said to be found sometimes on the beaches. Perhaps this alone will make their case with some readers.
Gorgeous and alluring
Generally, however, in folklore (or merlore, if you will) the merpeople are attractive, even gorgeous and alluring beings. Isn't that who you want to populate your imagination? They swim about, bothering nobody, bothered themselves only by their own loneliness. Often these creatures want to get married, you see. To people who don't have fins. It's a real misfortune for them. Though there's more than one fish in the sea, probably, for each of them, they're sick and tired of having only fish for friends. They'd rather snuggle up to some human meat.
Of course, assuming full human form is something that many of them can do quite handily. This is one reason there are many hundreds of stories of sailors, fishermen and explorers spotting a siren, a sjora, or some fetching creature who is actually a mermaid, and the results of these sightings tend to be mixed, trending toward the catastrophic. By a series of events, the mermaid may end up stuck in human form for an eternity (or what seems like one), widowed or otherwise abandoned. Or it may all end up with the dead body of a human involved, as in our Igpupiara accounts.
To assist the credulous, in the 16th and 17th centuries especially, there were those of a scientific proclivity, if not other aims, who gathered up some mermaid remains and shipped them here and there, placing them on public display in cabinets of curiosity, known also as Wunderkammern, or cabinets of wonder. This was especially popular in Europe. These cabinets were something like the precursors to modern museums, and they tended to get stuffed with all manner of natural and man-made oddities, some quite beautiful and astonishing, others rather suspect and even on the grotesque side but all of them lauded as authentic, I assure you.
A contemporary of Father Cardim, in fact, found an Igpupiara-type specimen, half maybe human, half somewhat fish- or dolphin-like, and the merbeing ended up in a cabinet for all to see. And believe in. But perhaps the most famous of all mermaids to be put onto public display was the Feejee Mermaid. P. T. Barnum got ahold of that one, and the sight of it was enough to curl your toes. Resembling nothing more than an ape-fish which is what it was, stitched together the hideous thing was gawked at for years in New York, Boston, London and elsewhere.
Well, seeing is believing, goes the adage; successful magicians and showmen know this. But I wouldn't want to go around suggesting that it's best to count the contents of your purse before you believe in something. If you ever see a real mermaid, either of the long dead and shriveled variety, or one that is very much alive, with long flowing hair and a dazzlingly sweet and beguiling personality, go ahead and believe your eyes. Go ahead.