Civilization as a Life-History Constraint: The Neonatal Vulnerability Hypothesis

This preprint presents a conceptual framework for why civilization emerges in some lineages but not others. The core claim is that intelligence alone is insufficient: civilization requires (i) inheritance mechanisms that preserve knowledge beyond individual lifetimes, (ii) sufficiently high cognition to build and transmit abstract structures, and (iii) a developmental driver that makes those structures necessary—high neonatal vulnerability with a long juvenile dependence period. When offspring are fragile and slow to mature, survival becomes contingent on stable caregiving, coordination, and the reliable transmission of accumulated practices. Over time, this life-history constraint converts knowledge into durable cultural scaffolds (norms, roles, teaching routines, symbolic narratives, proto-institutions), enabling true cumulative culture. The framework is applied to the comparative puzzle of why highly intelligent non-human species do not form civilization, and to a hominin context as a selection-based explanation for differential persistence among groups (including a qualitative account relevant to Neanderthal–Homo sapiens dynamics). The paper concludes with testable comparative predictions and clarifies the scope and limitations of the hypothesis. Type: Conceptual hypothesis / framework paper (not a claim of established fact).