evolvability
Compiled with AI assistance and selectively reviewed. Please consult the cited passages; the books remain the authoritative source. About this companion
Editorial synthesis · provisional
Definition
Evolvability is the capacity of an organism or lineage to generate viable heritable variation and thereby sustain further evolutionary innovation. The corpus treats this capacity itself as historically changing: developmental architectures, recombination and new organizational levels alter what variants can arise and persist. It differs from present fitness, guaranteed adaptation or an inevitable increase in complexity, and does not supply evolution with a predetermined target.
Explanation
The Extended Synthesis discussion makes the evolution of evolutionary capacity an explanatory problem, not something already explained merely by saying organisms evolve. RB2 develops the point through changing relations between genotype and phenotype: regulatory architectures can provide new routes for morphological variation. The relevant capacity concerns reachable variants, not just how rapidly a population currently reproduces.
Sexual recombination and major organizational transitions also change patterns of variation and inheritance. RB3 adds a comparison with modularity, which can contain change within subsystems while maintaining wider integration. These examples preserve different routes to evolvability rather than naming one substance or common numerical measure that all systems possess.
Existing organization can both enable further change and restrict it through dependencies. AB explains that a viable innovation must integrate with the organism it modifies, while RB3’s Riedl account emphasizes historical burden. Greater novelty or complexity is therefore not automatically advantageous, and a capacity for further change does not ensure that any particular future innovation will occur.
Scope and attribution
Retain the biological capacity and its historical alteration; technical modularity is a bounded comparison.
RB1 — The Real Book, Volume I: The Possible Is Real
Evolutionary capacity is itself a subject requiring explanation.
Occurrence locators: 147, 148.
RB2 — The Real Book, Volume II: Becoming Is Being
Changing developmental and reproductive architectures alter future evolutionary possibilities.
Occurrence locators: 269, 270, 271, 275.
Background used in the editorial explanation
Named theories and mechanisms are distinguished from neighboring background, homonyms and the author’s own synthesis. Reproduced AI passages retain their separate voice.