From [0]: > A shadow biosphere is a hypothetical microbial biosphere of Earth that would use radically different biochemical and molecular processes from that

From [0]: > A shadow biosphere is a hypothetical microbial biosphere of Earth that would use radically different biochemical and molecular processes from that of currently known life. Although life on Earth is relatively well studied, if a shadow biosphere exists it may still remain unnoticed, because the exploration of the microbial world targets primarily the biochemistry of the macro-organisms. [0] https://en.wikipedia.org/wiki/Shadow_biosphere https://en.wikipedia.org/wiki/Shadow_biosphere