Hyperdiffusionism is a pseudoarchaeological hypothesis that postulates that certain historical technologies or ideas were developed by a single people or civilization and then spread to other cultures. Thus, all great civilizations that engage in what appear to be similar cultural practices, such as the construction of pyramids, derived them from a single common progenitor. According to proponents of hyperdiffusion, examples of hyperdiffusion can be found in religious practices, cultural technologies, megalithic monuments, and lost ancient civilizations.
The idea of hyperdiffusionism differs from trans-cultural diffusion in several ways. One is the fact that hyperdiffusionism is usually not testable due to its pseudo-scientific nature. Also, unlike trans-cultural diffusion, hyperdiffusionism does not use trading and cultural networks to explain the expansion of a society within a single culture; instead, hyperdiffusionists claim that all major cultural innovations and societies derive from one (usually lost) ancient civilization. Ergo, the Tucson artifacts derive from ancient Rome, carried by the "Romans who came across the Atlantic and then overland to Arizona;" this is believed because the artifacts resembled known ancient Roman artifacts. One common hyperdiffusionist hypothesis states that the similarities among disparate civilizations were inherited from the civilization of a lost continent, such as Atlantis or Lemuria, which has since sunk into the sea. Egypt is also commonly featured in hyperdiffusionist narratives, either as an intermediate civilization that inherited its culture from such a lost continent and in turn passed it on to other civilizations or as a source of hyperdiffused elements itself.
