The ending of the original Little Mermaid is famously tragic. However, I was startled to discover that not everyone agrees on what that tragic ending was. There are even rumors that the author, Hans Christian Andersen, revised the story after publication and retconned the ending. What is the real ending of The Little Mermaid, and why did Andersen write it the way he did?
The Original Story
A mermaid princess rescues a human prince from drowning. Already fascinated by the world of humans, she becomes even more curious after this experience. She learns from her grandmother that although humans are shorter-lived than the mermaids, they have immortal souls; they will go to heaven, while merfolk merely dissolve into sea foam and cease to exist. The only way for a mermaid to get a soul is to marry a human. Enamored of the prince and longing for a soul, the mermaid goes to a sea witch to ask for legs so that she can go on land. The process will be torturous. The mermaid will have her tongue cut out. Although she’ll gain legs, it will be agony to walk. And if she fails and the prince marries someone else, it will mean instant death: “The first morning after he marries another your heart will break, and you will become foam on the crest of the waves.”
It's a dangerous gamble, but the mermaid goes through with it. She winds up at the prince’s palace, but he treats her like a small child and is oblivious to her pain. She cannot speak to tell him who she is, and he marries another woman. On the wedding night, the mermaid’s family gives her a knife; if she kills the prince, she can escape death and return to her old existence in the sea. Still no soul, but at least she’ll survive. However, the mermaid refuses. She leaps into the ocean to become sea foam, but unexpectedly, she is resurrected as one of the Daughters of the Air. Like merfolk, these spirits have three-hundred-year lifespans; unlike merfolk, they have the chance to earn souls and continue to Heaven. The tale ends with the explanation that children’s good behavior shortens the air-spirits’ time of wandering, and bad behavior lengthens it.
Behind the Story
Although The Little Mermaid is an original story, it was informed by older folktales and literature. In medieval stories like Melusine or traditional folktales like "The Lady of Llyn y Fan Fach," a human man marries a water sprite. However, he breaks some taboo - spies on her, scolds her, or hits her. She then vanishes forever, leaving him and their children behind. In the 14th-century poem "Peter von Staufenberg," a man marries a fairy who bestows fortune on him - but when he breaks his vows and weds a human princess, the fairy causes his death.
These stories inspired the Swiss philosopher Paracelsus. He wrote about his cosmology of elemental beings, where water elementals were called nymphs, melusines, or undines. In Paracelsus' work, an undine who marries a human will gain a soul, and any children born of their union will also have souls. However, if the husband ever rebukes his wife while they're on water, she will vanish forever. And if he marries someone else, the undine will kill him. Paracelsus directly referenced Peter von Staufenberg.
Paracelsus' elementals were widely influential. Among other things, they inspired a novella published in 1811: Undine, by Friedrich de la Motte Fouqué. The titular Undine is a water spirit. When she marries a human knight, she immediately gains a soul and transforms from a capricious sprite to a docile, affectionate bride. However, her husband feels deeply disturbed when he learns of Undine’s origins. Falling for another woman, he rejects Undine and she vanishes back into the water. When he is about to be married, Undine returns and unwillingly bestows a kiss of death on him. She grieves at his funeral and fades away, leaving only a fountain in her place.
There were quite a few other stories about mermaids popular in the early 1800s. B. S. Ingemann's De Underjordiske (The Subterraneans, 1817) included a mermaid who would turn into sea foam if she didn’t marry a human man. Hans Christian Andersen was familiar with all of these, as well as the German story of Lorelei the siren.
These inspirations showed up in Andersen's work long before The Little Mermaid. His 1831 book Skyggebilleder (Shadow Pictures) mentions that "the legend says, that the mermaid alone can receive an immortal soul from man's true love and Christian baptism" (Wullschlager 111). Also in 1831, Andersen published a poem titled "Havfruen ved Samsøe," which features a three-hundred-year-old mermaid dissolving into foam. He worked on another poem called Agnete and the Merman, based on a ballad about a human woman who abandons her merman husband and children. (Wullschlager 124)
However, the Little Mermaid was a direct response to Undine in particular. Andersen wrote to a friend in a letter dated February 1837, "I have not, like de la Motte Fouquet in Undine, let the mermaid's gaining an immortal soul depend on a stranger, on the love of another person. It is definitely the wrong thing to do. It would make it a matter of chance and I'm not going to accept that in this world. I have let my mermaid take a more natural, divine path."
Ever since publication, some critics have skewered the ending. The most frequent description is “tacked-on"; also artificial, forced, or false. To these critics, The Little Mermaid is a tragedy of unrequited love. The happy ending doesn’t fit (especially since it serves up the entirely unforeshadowed Daughters of the Air and some pompous moralizing). Phyllis M. Pickard dismissed the salvation plotline as "a mist of mysticism utterly unsuitable for children". And a 1908 edition of Forum called Andersen’s ending a “compassionate lie.” Even though he was the author, they felt so strongly that his text was flawed, that they rejected it outright. Andersen had written the wrong ending. The mermaid needed to die.
However, a growing number of critics have pushed back, arguing that the ending of The Little Mermaid is an organic part of the story. It isn't just about unrequited love; it's a story about salvation and spirituality. Again, this was Andersen's direct response to a longer tradition of soulless mermaids. The Little Mermaid is fascinated by the surface world and feels out-of-place among merfolk before she ever sets eyes on the prince. She is deeply distressed to learn that she will one day cease to exist, while humans will continue on to eternal life. Yes, she loves the prince, but her quest for a soul is also an inextricable part of the story. At the climax, her two motivations clash. She must choose between her love for the prince and her fear of death. Her selfless choice earns her a third option: the Daughters of the Air. It is a bittersweet ending; she doesn't marry the man she loves, and she still faces a long road to Heaven, but her death is not final.
You can see a similar ending in Andersen's 1858 tale "The Marsh King's Daughter," which also has the main character dissolve and die - it may seem sudden, except that the character's longing for Heaven has been foreshadowed.
The Little Mermaid was clearly very meaningful to Andersen. He once wrote, "it's the only one of my works that moved me as I wrote it." Many scholars have connected the plot to Andersen’s pining for his friend Edvard Collin, whose wedding took place the same year that Andersen wrote this story. Biographer Jackie Wullschlager suggested that The Little Mermaid symbolized Andersen’s way of coping. Although he could not be with Collin, he could focus on building an enduring legacy through his writing. The mermaid will never gain a soul from the prince or have children with him, but she will find another way to immortality. (Wullschlager 174-175)
An Alternate Ending?
A commenter to this blog mentioned hearing about Andersen writing an alternate ending. This sounded vaguely familiar. When I looked into this, I found a few mentions around the Internet indicating that Andersen had revised the story after publication. According to the rumor, the story was originally even bleaker, ending with the mermaid melting into sea foam. Only later were the Daughters of the Air added, in order to soften the story for children.
This rumor is false. Of course, we don’t have every single draft that Andersen worked on during development. However, plenty of scholars have studied Andersen’s work, and there’s nothing to support the retconned-ending rumor. Here’s what we know:
Andersen began planning "The Little Mermaid" by at least 1836. The first known working title was "Luftens Døttre" - The Daughters of the Air. Andersen later called the story "Havets Døttre," The Daughters of the Sea. Although the title seems to have changed multiple times, the air spirits were part of the story from very early on. The manuscript was completed on 23 January 1837. Andersen's letter about his mermaid earning her own soul was dated 11 February 1837, less than a month later.
"The Little Mermaid" first appeared in print in April 1837, in the first collection of Eventyr, fortalte for Børn (Fairy Tales Told for Children). In the preface, Andersen wrote that The Little Mermaid's "deeper meaning" might appeal best to adults - but "I dare presume, however, that the child will also enjoy it and that the denouement itself... will grip the child" (Johansen p. 239)
The story soon appeared in additional collections: Eventyr (Fairy Tales) in 1850, and Eventyr og Historier (Fairy Tales and Stories) in 1862. All of these versions have the same ending with the Daughters of the Air. There is no retconned "original ending."
In fact, the original ending from the manuscript was shortened. The draft featured more dialogue from the mermaid: "I myself shall strive to win an immortal soul . . . that in the world beyond I may be reunited with him to whom I gave my whole heart." (Wullschlager 168) I wonder if the original, longer section might have made the Daughters of the Air ending feel less abrupt to critics.
But to complicate matters, some people do remember reading versions where the mermaid simply dies.
One such version appears in the 1973 book Disney's Wonderful World of Knowledge, Volume 14 – translated from the Italian Enciclopedia Disney by Elisa Penna. It is a very short, almost summarized version, but the ending has significant changes. In Penna's version, the mermaid is about to kill the prince when he wakes up and innocently asks her what's going on. At his words, she repents. The whole interaction is transformed, making the mermaid morally ambiguous and giving the prince more agency.
It ends like so:
She fled from the room, knowing that she must soon die. By dawn, she felt the change coming on. Just as the witch had threatened, she was turning into foam--the beautiful white foam that caps the waves as they roll over the endless blue sea.
(This means that Disney went darker than Andersen. Try that one on for size.)
And another, Lucy Kinkaid's The Little Mermaid (1994) for beginning readers:
The little mermaid looks at the sleeping prince. She cannot harm him. She would rather die herself. The little mermaid throws the knife into the sea. Then she throws herself into the sea. She changes into sparkling foam and is never seen again.
There were also summaries which focused on the tragedy, and left out the more convoluted bittersweet ending. In the 1923 book Nobody's Island, a character remarks that the little mermaid "didn't marry the Prince, and... on the night of his marriage with another she faded away and passed into the foam of the sea."
I knew that many storybook retellings softened the ending in a Disney-like way, but I hadn’t realized that some went the other direction and killed off the mermaid permanently. As already noted, many critics disliked Andersen’s ending. It seems that some storytellers also felt the need to leave the story as a tragedy.
The rumor that Andersen rewrote his ending may have arisen for a number of reasons.
The rumor is easily debunked, but I would also argue that the ending of The Little Mermaid is not tacked on either literally or metaphorically. It is a natural part of the story. It was not added after the fact. This should be clear from Andersen's life, his inspirations, and his spirituality. It's also fascinating how The Little Mermaid was a response to Undine. Later stories, like Oscar Wilde's "The Fisherman and His Soul" and Disney's Little Mermaid, responded in turn with different spins on the subject. It's an evolving conversation.
(Edited 7/14/23 with page number correction)
The cecaelia is, in modern Internet parlance, a common term for a mermaid that has octopus limbs rather than a fish tail. Another frequently used name is "octomaid." A famous example of an octopus-limbed mermaid is Disney's sea witch Ursula. I want to focus on "cecaelia," an intriguing name - both singular and plural and pronounced seh-SAY-lee-uh. Most importantly... where did it come from?
The etymology, at first look, is baffling. It starts with the same syllable as the word "cephalopod" - cephalo (head) + pod (foot) - but that's not much to go on. It is not related to the Latin girls’ name Cecilia, or to the limbless amphibians called caecilians. Both of those come from the word “caecus,” meaning “blind.”
In Making a Splash (2017), Philip Hayward suggests that the word was inspired by a comic book character from the 1970s. The short comic "Cilia" appeared in Warren Publishing's Vampirella Magazine issue 16 in April 1972. It was reprinted in Issue 27, September 1973. Cilia, a beautiful mermaid-like woman with three tentacles in place of each leg, rescues a sailor from drowning. Although her appearance is horrifying to humans, she is a kind and gentle spirit and her relationship with the sailor grows into love. The story ends tragically when the prejudiced human community discovers her.
Cilia refers to her species as "cilophyte." The term was probably invented by the author - the etymology, again, is murky. As pointed out on the TV Tropes page for this comic, "phyte" means growth and "cilo" could be related to "cilium" (fine hairs), Scylla (a Greek sea monster), or "kilo" (Greek for thousand). Perhaps it was also meant to look similar to "cephalopod."
As Hayward points out, the word "cecaelia" does not appear until around 2007 or 2008. So I went diving.
The "cecaelia" can be traced to a Wikipedia page created in March 2007. (Thank you to Wikipedia administration for their help recovering the page information!) According to the earliest version of the page, the cecaelia is "a composite mythical being." The name "is a corruption of coleoidian, a genus of squid, and derives originally from a comic in Eerie magazine from the early 1970s featuring an octopoidal character named Cecaelia" who "helped a shipwrecked sailor back to land." This is apparently meant to be "Cilia;" the plot is right, as is the publisher. Later versions of the page corrected the character information. In addition, "Coleoidea" is the subclass of cephalopods which includes octopus, squid and cuttlefish.
The only source in this first version was a link to a discussion thread on seatails.org, a mermaid-enthusiast messageboard. Created by Kurt Cagle, Seatails began as a print magazine that ran briefly in 1987 and then moved to the web, shifting through several platforms over the years. In the early 2000s, it existed in a discussion board format. Members included numerous artists and collectors who were interested not only in mermaids but in other hybrid mythological creatures.
The link was apparently quickly deleted, since it did not meet Wikipedia's standards for sources. Unfortunately, Seatails is now defunct and the discussion thread in question cannot be reached even through the Internet Archive.
In addition to the information from Wikipedia, I contacted Kurt Cagle via the current Seatails page on the art site DeviantArt. I also contacted a DeviantArt user called EVAUnit4A, who identified themself as a user of the old message board and a contributor to the Cecaelia Wikipedia page.
Based on that, here are the main points of the history of the cecaelia as I understand it:
If the comic inspired all this, why wasn’t the species term “cilophyte” adopted instead? First of all, it seems it took a while to track down the specifics of the comic. EVAUnit4A suggested that perhaps cilophyte was “too unwieldy to type out properly" and that people may have wanted "a word closer to real octopus and squid." When I reached out to Cagle, he wrote back that another influence was the song “Cecelia” by Simon and Garfunkel, about a fickle and demanding lover.
According to Cagle, “I actually kind of forgot about [the cecaelia] after a while, and was surprised to find the term gaining traction a few years later.”
I have to take a quick detour here. Wikipedia is near-universally used, often more easily than print encyclopedias because it’s just a push of a button away. But it can also be edited by anyone at any time. As a result, it has strict guidelines. One of the most important is that "Wikipedia is not for things made up one day." The page for this rule, which has existed since 2005, sums up many of Wikipedia's policies, including that articles must be on something notable and famous, and must include verifiable sources (such as a reliable book or article).
Thus, the Wikipedia page for Cecaelia had a tortured history. Although there were quite a few works that featured such creatures, the name itself was an original creation. The page was originally Cecælia, then changed to Cecaelia, moved in 2010 to "Octopus person" as "a more proper title," and the last holdout was finally deleted in 2018. It now redirects to "List of hybrid creatures in folklore," specifically the section "Modern fiction." The word pops up occasionally on other pages - as of the time of writing, the Wikipedia page for Ursula calls her a cecaelia.
As previously seen, the oldest versions of the "cecaelia" page were honest about its origins. Via the Wayback Machine, a version from December 2008 said even more definitively that the term was a "distorted mispronounced" version of Cilia. This clarification, buried in the paragraph and easier to miss, was ultimately lost. By April 27, 2010, when the page existed as "Octopus Person," the description of the comic had been deleted and only a brief and confusing reference to "Cilia" remained.
Unclear language was another problem; throughout many edits, the page called the cecaelia a “composite mythical being.” A composite myth is constructed from shorter stories or fragments of tradition, often intended to recreate lost legends. However, readers could have taken the phrase in a couple of ways. In the case of the cecaelia, they might read it as “a being of composite myth based on various media," or they might read it as “a mythical being that is a composite of human and octopus.”
Readers took it the second way, with many adopting the term in the belief that it was traditional. Here's one example from a blog in 2008 which specifically gives Wikipedia as its source. Looking through some of my writing from eight years ago, I found that I also used the term without a second thought after encountering it on Wikipedia.
The word spread fairly quickly. The word was picked up across DeviantArt. In April 2008, a user on the roleplaying-based Giant in the Playground Forums posted a writeup for "cecaelias" as a monster race. Cecaelia was the name of an octopus-woman monster in AdventureQuest Worlds, an MMORPG released in 2008. Pathfinder's RPG Bestiary 3, released in 2011, featured the Cecaelia as a monster, and the word also features in Cassandra Clare's Bane Chronicles (2015).
Most recently, the Disney tie-in novel Part of Your World by Liz Braswell (2018) refers to Ursula as a cecaelia. This was, to my knowledge, the first time Ursula had ever received this name in canonical material. Previously she was only called a cecaelia by fans, as in the fan-run database disney.wikia.com.
So are there any traditional sources that feature octopus-like mermaids?
In a Nootka tale from the Pacific Northwest, the animal characters Octopus and Raven show up apparently in human form. When Octopus is angered, her hair (braided into eight sections) transforms into powerful tentacles (Caduto & Bruchac 1997.) I don't know what the characters of Octopus and Raven might have been called in the original language, but according to firstvoices.com, the Nuu-chah-nulth word for Octopus is tiiłuup, and Raven is quʔušin.
"The Devil-Fish's Daughter," a Haida tale also from the Pacific Northwest, features devil-fish (octopi) who can take human form. But this is more a case of animal shapeshifters, not hybrids.
Native Languages, a most helpful site for American Indian legends, has little to say on the octopus. It notes only that octopi "do not play a major role in most Native American mythology."
Some pages on the cecaelia, apparently derived from Wikipedia, claim that the artist Katsushika Hokusai (1760-1849) painted octopus-woman hybrids. I have found no evidence for this. Hokusai did paint the erotic 1814 “Dream of the Fisherman’s Wife," which features a woman with octopi. (If you look it up, be advised that it is NSFW.)
The "sea monk" or monk-fish of medieval bestiaries also looks vaguely tentacley. Theories on what inspired it include squid and angelshark.
Finally, Scylla, a sea monster of Greek myth, is said by Homer to have twelve dangling feet. She might be understood as somewhat like a squid. Homer's Scylla is not particularly humanoid, but the term has gained some popularity in recent years.
In essence, there is no traditional octopus mermaid. Only in the 20th century did the idea of octopus-human hybrids gain popularity as a symbol of horror and evil. H. P. Lovecraft's squid-faced god Cthulhu first appeared in 1928, later to influence the monstrous "mind flayers" of Dungeons and Dragons. The tragic Cilia the cilophyte, from 1972, has an appearance disturbing to humans despite her kind soul. And in 1989, Disney used the grasping, writhing half-octopus Ursula to contrast their innocent heroine in The Little Mermaid. (Their original concept art had Ursula as a more traditional fish-tailed mercreature.)
However, this budding concept had no unified name. "Cilophyte" was an obscure and unique creation. "Cecaelia" was born around 2007 on the Seatails site, as a name inspired by "Cilia," "cilophyte," "coleoidea," and the alluring Cecelia of Simon and Garfunkel. Artists and other users on the discussion board popularized the title. The Wikipedia page boosted the concept, with many readers taking it to mean that the cecaelia was an established legend. At this point, it's taken on a life of its own, although there are a few other names floating around as well.
Sirens are not the same as mermaids. Mermaids are half-fish women, but sirens (the ones with the hypnotic singing voices) are half-bird women from Greek mythology. On the other hand, sirens and mermaids have been conflated for a long time. When did it begin?
Sirens first appear in Homer's Odyssey in the 8th century B.C. Homer doesn’t really describe them at all. All we know is that their song will ensnare anyone who hears it.
Later writers specify that sirens possess wings, or that they have the heads of beautiful women and bodies of birds. They may have drawn on Near Eastern myth-creatures like the ba of Egyptian cosmology. Human-faced birds were closely associated with the otherworld. Sirens mourned the dead in funerary art, and they were connected to Persephone, queen of the Underworld. Homer may have felt no need to describe sirens, since his audience would have known the context. Despoina Tsiafakis, however, suggests that the sirens could have gained avian attributes after Homer, when others sought to illustrate his work. (Tsiafakis p. 74)
Meanwhile, fish-tailed people were a subject of art for a long time. They showed up in Mesopotamian art at least from the Old Babylonian Period (c. 1830 BC – c. 1531 BC). These were usually men, like the god Ea, but fish-tailed women sometimes appeared.
Then in medieval times, sirens stopped being bird-ladies and became fish-ladies. But birds and fish aren't typically interchangeable. What happened?
Even in Ancient Greece, sirens were already evolving. Male sirens used to appear in art, but disappeared as artists' attitudes shifted (Tsiafakis). Now all female and anthropomorphized, sirens changed from monstrous birds with human heads to instrument-playing women who happened to have wings and bird feet.
The emphasis moved to their beauty and allure. In some late Greek art they appeared as women with no avian attributes at all (Harrison 1882). As the legend traveled abroad, things got even more complicated.
In his Commentary on Isaiah (c. 404-410 AD), Jerome uses siren as a translation for a couple of words. Regarding thennim (tannim, or jackals) he adds, "Moreover, sirens are called thennim (תנים), which we interpret as either demons, or some kind of monsters, or indeed great dragons, who are crested and fly."
So now, apparently, sirens are dragons. This sets the stage for the next stage of sirens, where they are symbols of evil and temptation.
In his Etymologies, compiled between c. 615 and the 630s, Isidore of Seville seems split on the issue. He tells us of "three Sirens who were part maidens, part birds, having wings and talons.” But he goes on to explain that “in Arabia there are snakes with wings, called sirens (sirena).”
In the Liber monstrorum (Book of Monsters), from the late 7th-early 8th century, the anonymous author proposes "a little picture of a sea-girl or siren, which if it has a head of reason is followed by all kinds of shaggy and scaly tales.”
Then there’s the Physiologus, a bestiary which originated as a 2nd-century Greek text. As pointed out by Wilfred P. Mustard, the original Physiologus doesn't mention sirens. However, translations varied widely and contradictions were rampant. In a 9th-century copy from Bern, even though the text described sirens as avian beings, a confused illustrator added an illustration of a half-serpent woman. (Dorofeeva 2014) A early 12th-century German edition gives Sirene as "meremanniu," and a Middle English translation "mereman." (Pakis 2010) Despite the discrepancies between editions, the Physiologus was a universally popular source for creators of medieval bestiaries. People later in this list, like Bartholomaeus and Geoffrey Chaucer, mentioned it by name when describing their siren-mermaids.
Some authors seesawed on the subject. Guillame le Clerc, in his Bestiaire (c. 1210) said that the beautiful, murderous siren has the lower body of "a fish or a bird." Bartholomaeus Anglicus, in De proprietatibus rerum, “On the Properties of Things” (1240), was careful to cover all his bases. "The Mermayden, hyghte Sirena, is a see beaste wonderly shape," he said, and proceeded to describe fish-women, fowl-women, crested serpents, and pretty much everything in between.
In quite a few illustrations, "transitional" sirens held sway. In the Northumberland Bestiary (c.1250-60), sirens are a kind of human-bird-fish hybrid with amphibious webbed feet.
Or take this illustration, where the siren is a winged merperson.
By the 14th century, the siren's identity had become standardized as a fish-tailed temptress with a hypnotic voice. The words siren and mermaid were interchangeable.
When Geoffrey Chaucer translated Boethius' Consolation of Philosophy, (1378-1381) he translated sirenae as meremaydenes. Then, in Nonne Preestes Tale (1387-1400), he described a "Song merier than the mermayde in the see."
Male Regle (The Male Regimen) by Thomas Hoccleve (1406)
"...spekth of meermaides in the see,
How þat so inly mirie syngith shee
that the shipman therwith fallith asleepe,
And by hir aftir deuoured is he.
From al swich song is good men hem to keepe."
In Edmund Spenser's Faerie Queene book II (1590s), "mermayds . . . making false melodies" tempt the heroes. These mermaids, Spenser explained, were once "fair ladies" but arrogantly challenged the "Heliconian maides" (the Greek Muses) and were turned to fish below the waist as punishment. (This sort of ties in with Pausanias’ Description of Greece from around the 2nd century A. D., where the Sirens and Muses had a singing competition. The Sirens lost and the Muses plucked out their feathers to make into crowns.)
The original version of Sirens never fully went away. William Browne, in the Inner Temple Masque (1615) described Syrens "with their upper parts like women to the navell, and the rest like a hen."
Still, sirens and mermaids remained generally synonymous, with few exceptions. English has the word mermaid for the fish-woman and siren for the mythological bird-woman. In Russian, too, the sirin has survived as a bird-woman. But in many other languages, “siren” is The Word for mermaid. According to Wilfred Mustard, "In French, Italian and Spanish literature, the Siren seems to have been always part fish." Languages that only use sirena or some variant for "mermaid" include Albanian, Basque, Bosnian, Croatian, French, Galician, Italian, Latvian, Polish, Portuguese, Romanian, Serbian, Slovenian, and Spanish. Aquatic mammals like manatees and dugongs belong to the order Sirenia. A congenital disorder that causes children to be born with fused legs is called Sirenomelia.
Sirens have always been associated with the ocean and with sailors. They are the children of a river god. It makes sense that people would portray them as part-fish. But could the change have been intentional, at least on some parts? Jane Harrison suggests that “the tail of an evil sea monster” was meant to emphasize the siren’s corruption and darkness (p. 169). The book Sea Enchantress: The Tale of the Mermaid and her Kin proposes that the intention was to give the beautiful sea-maiden “a graceful fish-tail, since a bird-body is hardly seductive in appearance” (p. 48). Different lines of thought there, but the same effect. Whatever caused this evolution, it's clear that the modern mermaid is truly the direct descendant of the ancient Greek siren.
Researching folktales and fairies, with a focus on common tale types.