The original Greek sirens were bird-women, not mermaids
Homer never described what the sirens looked like. Greek artists soon gave them the bodies of large birds with women's heads, often clutching a lyre. The fish-tailed version we picture today crept in much later, through medieval bestiaries and an 8th-century catalogue of monsters written in England.
Sirens first sing in the Odyssey, in the episode where Odysseus steers his crew safely past their deadly voices. Homer left their appearance to the imagination. Roman poets placed them on small islands called Sirenum Scopuli, and later writers tried to pin down their flowery island, Anthemoessa, at Cape Pelorum, near Paestum or on Capri, always among cliffs and rocks.
By the 7th century BC, painters routinely showed them as birds with human heads, feathers and scaly feet, perhaps borrowing from the ba-bird of Egyptian religion. Apollonius of Rhodes, in his 3rd-century BC Argonautica, described them in words as half woman, half bird. Over time the human part grew, until sirens had women's torsos on bird legs, playing the kithara or the pipes called aulos. Male sirens existed in early art but vanished around the 5th century BC. The 10th-century Byzantine Suda offered its own twist: sparrow above the chest, woman below.
Mermaid-like sirens were not wholly new, since an Athenian earthenware bowl and a terracotta lamp show fish-tailed tritonesses. The first written description of a siren as a sea-girl with a scaly tail comes from the Liber Monstrorum, an Anglo-Latin catalogue from the early 8th century AD. Illustrated copies of the Physiologus, beginning with the 9th-century Berne manuscript, and the bestiaries that followed cemented the half-fish look, though some still mixed wings and claws with a tail.
Nobody agrees on the name's origin. Robert Beekes suggests a word older than Greek. Others tie it to Greek terms for a cord and for fastening, making a siren a binder who entangles by song, a neat echo of Odysseus lashed to his mast. Marcel Cohen proposed a Biblical word for wasp. Medieval Christian art turned the creature into a warning about female temptation, and the word still labels a dangerously attractive woman.
Source: Siren (mythology)
