# Darwinian Evolution > **Machine-Evolution Nexus:** [[articles/Digital Darwinism and the Invisible World of Machine Evolution|Digital Darwinism and the Invisible World of Machine Evolution]] places this concept within the history and governance of substrate-independent evolution. **Domain:** Evolution / Digital Life **Doc Type:** Canonical Wiki Node **Maturity:** Developed ## Definition Darwinian evolution is iterated change in populations produced when heritable variants differ in survival, persistence or reproduction under environmental constraints. ## Machine-Evolution Context Its substrate-neutral core can operate in chemistry, machine instructions or cellular-automaton states. The article uses five tests: heritable information, variation, differential success, constraint and repetition across generations. ## Continuity and Evidence Boundary The term should not be applied merely because a system changes, optimizes, branches or becomes complex. Darwinian dynamics do not establish life, sentience or personhood. ## Relationships [[wiki/Heritable Variation|Heritable Variation]], [[wiki/Differential Reproductive Success|Differential Reproductive Success]], [[wiki/Population|Population]], [[wiki/Ecological Constraint|Ecological Constraint]] ## Sources / Provenance - Darwin, _On the Origin of Species_; Lewontin, “The Units of Selection” (1970).