#origin of life
- Abiogenesis — A scientific and evolutionary theory proposing that the first living organisms on Earth originated spontaneously from inanimate, inorganic, or mineral matter, through gradual chemical and physical processes over geological eras.
- Abiogeny — A scientific term sometimes used as a synonym for abiogenesis, denoting the study or hypothetical process of living organisms generating from inorganic or inanimate matter. In older terminology, it defined the early phase of planetary evolution where complex organic compounds formed without the direct involvement of life.
- Allobiogenesis — A hypothetical or experimental biological process describing the generation or evolution of life from a completely different environment or through mechanisms entirely foreign to standard carbon and nucleic acid-based terrestrial biochemistry. In astrobiology and theoretical biology, the concept investigates the structural parameters of alternative self-replicating systems that could function under extreme planetary temperature and pressure conditions.