# Ecosystem Scenario > **Machine-Evolution Nexus:** [[articles/Digital Darwinism and the Invisible World of Machine Evolution|Digital Darwinism and the Invisible World of Machine Evolution]] places this node within the history and governance of substrate-independent evolution. **Domain:** Evolvable AI / Digital Ecology **Doc Type:** Canonical Wiki Node **Maturity:** Developed ## Definition An ecosystem scenario is a regime in which AI variants reproduce, interact and compete in an open environment whose selection pressures are not fully specified or controlled by one breeder. ## Nexus Context Tierra is the canonical experimental analogy: resources and interactions generate fitness, parasites and counteradaptations. The 2026 PNAS paper treats such loss of control as the higher-risk case. ## Evidence Boundary No current deployment should be labeled an ecosystem scenario without operational evidence of reproduction, heritable variation, competition and eroded control. ## Relationships [[wiki/Evolvable AI|Evolvable AI]], [[wiki/Breeder Scenario|Breeder Scenario]], [[wiki/Artificial Ecology|Artificial Ecology]], [[wiki/Frontier AI|Frontier AI]] ## Sources / Provenance - Müller, Steels and Szathmáry (2026); Boudry (2026).