Symbiosis (from
Greek σύν "together" and βίωσις "
living") is close and often long-term interaction between two different biological
species. In 1877
Albert Bernhard Frank used the word
symbiosis (which previously had been used to depict people living together in community) to describe the relationship in
lichens. In 1879, the
German mycologist Heinrich Anton de Bary defined it as "the living together of unlike organisms."