Endless Forms Most Beautiful and Most Wonderful: Ruliobiology and the Theoretical Foundations of Biological Form

gist

Stephen Wolfram proposes ruliobiology, a metamodel of biology built from simple cellular automaton rules shaped by adaptive evolution. Evolving symmetric 5-color rules for lifetime, he finds organ-like modules, random connective tissue, convergent evolution, conserved early development and extreme side-effect traits. He argues biological form is mostly frozen computational irreducibility selected by evolution, not a direct imprint of selection.

ideas

• Rulioorganisms as a metamodel. Rules act as genotype and the grown pattern as phenotype; random rule mutations are kept only if they do not reduce lifetime, giving a fossil-record-like sequence of breakthroughs.
• Polyplexy, novelty at every scale. Zooming into evolved patterns reveals different structures at each scale, unlike fractal nesting or the Mandelbrot set, with modular organ-like parts separated by random connective tissue.
• Extremes arise as side effects. In 100,000 evolved samples, exotic widths, colors and shapes appear in distribution tails without being selected, and selecting directly for a trait gives only modestly more extreme values.
• History matters but is hard to reverse. Early development gets conserved, lineages commit to forms and keep features like purple patches, and convergent evolution reaches similar pincers or diamond shapes by different paths.
• Implications for astrobiology. Wolfram argues these features should be general to adaptive evolution, so mechanoidal modular complexity could be a signature of long evolutionary processes elsewhere.

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