Summarizes the theory that as human cultures evolve, they will, unless destroyed by some prior event, ultimately destroy themselves by exhausting their essential resources, by damaging their ecology until it will not sustain them, or both." (Author/AL)

The meaning and history of the term symbiosis is discussed. The role of symbiosis in evolution is suggested. Research in the field of endocytobiology on symbiotic relationships is proposed. (CW)