# Digital Organism > **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:** Artificial Life / Digital Evolution **Doc Type:** Canonical Wiki Node **Maturity:** Developed ## Definition A digital organism is an executable, reproducing computational entity used as an individual in an artificial-life population. ## Machine-Evolution Context In Tierra and Avida, instruction sequences copy with mutation and compete for scarce processor time or memory, enabling observable Darwinian evolution and ecological interaction. ## Continuity and Evidence Boundary The label is operational within a model. It does not settle whether the entity is alive in every philosophical sense, conscious, sentient or a rights-bearing person. ## Relationships [[wiki/Avida|Avida]], [[wiki/Tierra|Tierra]], [[wiki/Digital Population|Digital Population]], [[wiki/Consciousness|Consciousness]] ## Sources / Provenance - Lenski et al., _Nature_ 423 (2003); NASA Astrobiology, “Computing the Origin of Life.”