Law as Extended Phenotype: Toward an Evolutionary Theory of Legal Systems

This article proposes a theoretical framework grounded in Richard Dawkins' concept of extended phenotype and Daniel Dennett's memetic theory to explain the evolution of legal systems. Unlike previous evolutionary approaches to law that treated legal rules as organisms subject to natural selection, I demonstrate that legal institutions constitute extended phenotypes of cultural replicators—legal memes—whose fitness depends on their capacity to create self-reinforcing reproductive machinery. Legal norms function not as selected entities but as selection mechanisms, building the professional structures, educational systems, and enforcement apparatus that ensure their own replication. The framework generates novel empirical predictions distinguishable from rival theories: (1) legal concepts that generate specialized professional communities will spread more successfully than substantively superior alternatives; (2) transplant success correlates with phenotypic compatibility rather than normative quality; (3) crisis events trigger meme recombination rather than conscious design; (4) legal education functions as deliberate phenotypic engineering. Preliminary evidence from corporate liability regimes, compliance mechanisms, and constitutional crises supports these predictions. I establish falsifiability criteria following Popperian methodology and present five computational tools operationalizing the theory: JurisRank (measuring concept fitness through citation networks), RootFinder (tracing memetic genealogies), Legal-Memespace (mapping doctrinal evolution), Peralta-Metamorphosis (quantifying constitutional degradation), and Iusmorfos (integrated evolutionary analysis framework). These open-source tools transform evolutionary legal theory from speculative framework to testable research program.