Bioevo-Cybernetic Thresholds in Action: Mechanistic Demonstrations of Major Evolutionary Transitions

Abstract Major evolutionary transitions—from prolonged unicellular organization to eukaryogenesis and multicellularity— have been hypothesized to arise from regulatory thresholds governing system-level complexity, integration, and functional asymmetry. Building on a recently developed bioevo-cybernetic framework, this study demonstrates how such thresholds generate mechanistically interpretable and quantitatively testable evolutionary outcomes. Numerical simulations of the Stage 2 → Stage 3 transition show that joint increases in energy throughput, regulatory integration, and feedback gain trigger abrupt activation of system-level complexity and modular internal control. Analyses of the Stage 3 → Stage 4 transition further reveal that multicellularity emerges only when differentiation, asymmetry, and energetic support collectively surpass a regulatory gating threshold. Bifurcation analyses of regulatory gain highlight the conditional stability of these transitions under stochastic perturbations. Together, time-series, phase-space, and bifurcation results provide a reproducible demonstration of bioevo-cybernetic thresholds, establishing a quantitative framework for simulation-based, synthetic, and experimental studies of evolutionary dynamics.