Shapeshifting

In mythology, folklore and speculative fiction, shapeshifting (or metamorphosis) is the ability of a being or creature to completely transform its physical form or shape. This is usually achieved through an inherent ability of a mythological creature, divine intervention, or the use of magic.

The idea of shapeshifting is present in the oldest forms of totemism and shamanism, as well as the oldest extant literature and epic poems, including works such as the Epic of Gilgamesh and the Iliad, where the shapeshifting is usually induced by the act of a deity. The idea persisted through the Middle Ages, where the agency causing shapeshifting is usually a sorcerer or witch, and into the modern period. It remains a common trope in modern fantasy, children's literature, and works of popular culture.

The most common form of shapeshifting myths is that of therianthropy, which is the transformation of a human being into an animal or conversely, of an animal into human form. Legends allow for transformations into plants and objects, and the assumption of another human countenance (e.g. fair to ugly).

Popular shapeshifting creatures in folklore are werewolves and vampires (mostly of European, Canadian, and Native American/early American origin), the Huli jing of East Asia (including the Japanese kitsune), and the gods, goddesses, and demons of numerous mythologies, such as the Norse Loki or the Greek Proteus. Shapeshifting to the form of a wolf is specifically known as lycanthropy, and such creatures who undergo such change are called lycanthropes. Therianthropy is the more general term for human-animal shifts, but it is rarely used in that capacity. It was also common for deities to transform mortals into animals and plants.

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