Therianthropy refers to the metamorphosis

Metamorphosis

Metamorphosis is a biological process by which an animal physically develops after birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation...

 of human

Human

Humans are the only living species in the Homo genus...

s into other animals. Therianthropes are said to change forms via shapeshifting

Shapeshifting

Shapeshifting is a common theme in mythology, folklore, and fairy tales. It is also found in epic poems, science fiction literature, fantasy literature, children's literature, Shakespearean comedy, ballet, film, television, comics, and video games...

. Therianthropes have long existed in mythology

Mythology

The term mythology can refer either to the study of myths, or to a body or collection of myths. As examples, comparative mythology is the study of connections between myths from different cultures, whereas Greek mythology is the body of myths from ancient Greece...

, appearing in ancient cave drawings such as the Sorcerer

The Sorcerer (cave art)

The Sorcerer is one name for an enigmatic cave painting found in the cavern known as 'The Sanctuary' at Trois-Frères, Ariège, France, made around 13,000 BC. The figure's significance is unknown, but it is usually interpreted as some kind of great spirit or master of the animals...

 at Les Trois Frères.

The term therianthropy comes from the Greek theríon, θηρίον, meaning "wild animal" or "beast" (impliedly mammalian), and anthrōpos, άνθρωπος, meaning "human being".