Wikipedia posted:

In Greek mythology, the harpies (snatchers[1]) were mainly winged death-spirits (Harrison 1903, p. 176ff), best known for constantly stealing all food from Phineas. The literal meaning of the word seems to be "whirlwinds".

The harpy could also bring life. A harpy was the mother by the West Wind Zephyros of the horses of Achilles (Iliad xvi. 160). In this context Jane Harrison adduced the notion in Virgil's Georgics that mares became gravid by the wind alone, marvelous to say (iii.274).

Though Hesiod (Theogony) calls them two "lovely-haired" creatures, harpies as beautiful winged bird-women are a late development, in parallel with the transformation of the "Siren, a creature malign though seductive in Homer, but gradually softened by the Athenian imagination into a sorrowful death angel" (Harrison p. 177). On a vase in the Berlin Museum (Harrison, fig. 19), a harpy has a small figure of a hero in each claw, but her head is recognizably a Gorgon, with goggling eyes, protruding tongue and fangs.