The National Oceanic and Atmospheric Administration (NOAA), which usually deals with environmental matters like tsunamis and hurricanes, recently took the strange step of posting a statement on their website denying that mermaids exist.

In a post titled, “No Evidence of Aquatic Humanoids Has Ever Been Found,” NOAA notes that:

The belief in mermaids may have arisen at the very dawn of our species. Magical female figures first appear in cave paintings in the late Paleolithic (Stone Age) period some 30,000 years ago, when modern humans gained dominion over the land and, presumably, began to sail the seas. Half-human creatures, called chimeras, also abound in mythology — in addition to mermaids, there were wise centaurs, wild satyrs, and frightful minotaurs, to name but a few. But are mermaids real? No evidence of aquatic humanoids has ever been found.

Why would NOAA bother to pour cold water on mermaids? After all, there are many mythical things that the government doesn’t explicitly deny exist. The United States Bureau of Mines doesn’t issue statements clarifying that no dragons or trolls have been discovered in underground caves or mines, for example.

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So why mermaids? And why now?

Credit (or blame) Animal Planet (a branch of Discovery), which last month aired a TV show called "Mermaids: The Body Found." It was a documentary-style show that “paints a wildly convincing picture of the existence of mermaids, what they may look like, and why they’ve stayed hidden…until now,” according to the show’s press Web page. Indeed, it says, “'Mermaids: The Body Found' makes a strong case for the existence of the mermaid…”

Though the filmmakers acknowledged that the film is science fiction, for many people it was indeed “wildly convincing.” The show was an "X-Files" type fanciful mix of state-of-the-art computer generated animation, historical fact, conspiracy theory and real and faked footage sprinkled with enough bits of scientific speculation and real science to make it seem plausible. In fact, there were even interviews with real NOAA scientists. As with all good science fiction, there’s a grain of science and truth to it: the so-called “aquatic ape” idea it touted (suggesting our evolutionary ancestors may have lived in marine environments) is a real hypothesis, but has nothing to do with mermaids.

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As New York Times reviewer Neil Genzlinger noted, the story is “a fictional account built on a few strands of fact and made to look like an actual documentary. If you know those ground rules, it’s a rather enjoyable and intriguing piece of work, in the same vein as 'The Blair Witch Project'.” It seems that many people weren’t aware of those ground rules, and were fooled into thinking that there was more fact than fancy in the show.

The title (and premise) of the show (“The Body Found”) is of course completely fictional but hardly the first faux-documentary show to fool people. A 1995 Fox television special called "Alien Autopsy: Fact or Fiction" used many of the same techniques and convinced many people with superficially plausible (though faked) footage of an alien autopsy.

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With a sly wink, "Mermaids: The Body Found" presented a fictional story in fake-documentary format for added plausibility. There’s a reason why so many horror films (especially supernatural-themed ones) claim to be based in fact or “on a true story,” when they’re not: it adds realism and interest. The program posed scientifically non-sensical questions like, “If massive whales haven’t been discovered until recently, it answers why we haven’t been able to detect mermaids yet?” (Answer: Whales have been studied for many decades and are not a “recent discovery;” the fact that genetic testing has revealed new subspecies of whales says nothing about why completely unknown mythical animals like mermaids have never been discovered.)

Interestingly, NOAA has a history of addressing a few legends relating to oceans, including Atlantis and the Bermuda Triangle. Part of NOAA’s mission is public education and outreach, and if they get enough queries from the public on a given topic (even a mythical one) it’s likely they will address it.