Machine elves (also known as fractal elves, self-transforming machine elves) is a term coined by the late ethnobotanist, writer and philosopher Terence McKenna to describe the apparent entities (described as "elves") that have been reported by users of dimethyltryptamine. References to such encounters can be found in many cultures ranging from shamanic traditions of native Americans to indigenous Australians and African tribes, as well as among western users of these substances.