Phenomena modelled
Evolution & Genetic Algorithms
Natural selection, genetic algorithms, and digital organisms.
Evolving solutions with mutation, crossover and selection: from bitstrings and arithmetic trees to self-replicating code and digital creatures.
Models 7
7 models in this collection.
Biology & ecologyGenetic Algorithm
How tightly can a population settle on a peak while it keeps mutating?Fifty two-gene genomes climb a single fitness peak by tournament selection, uniform crossover and Gaussian mutation. Each creature sits at the point its genes encode.
Biology & ecologySymbolic Regression
How long does evolution sit on a flat line before it finds the cubic?Genetic programming. Sixty formula trees built from add, sub, mul, v, 1 and 2 evolve until one of them draws the grey target curve, v³ − 2v.
Biology & ecologyBoolean Multiplexer
How many generations does it take to wire both address bits in correctly?Genetic programming on Koza's 6-multiplexer benchmark. Circuits built from and, or, not and if evolve until one gets all 64 input cases right.
Biology & ecologyAvida
Why does every avidian end up with both extra abilities, even where those tasks pay nothing?A sketch of Avida's reward scheme. Avidians earn energy by performing logic operations, harder operations pay more, and mutation can unlock the two harder ones.
Biology & ecologyTierra
Can parasites that copy twice as fast ever get rid of their hosts?A small cartoon of Thomas Ray's Tierra. Programs copy themselves into neighbouring cells; short mutants copy twice as fast but only when a full-length host is nearby.
Physics & patternsStringmol
Can replicators that copy whatever they bind survive in a soup where most molecules never copy anything?Replicators copy whatever molecule they bind, whether another replicator, a catalyst that feeds them or a substrate that gives nothing back. Feedstock and random decay hold the soup at about 200 molecules.
Biology & ecologyBFF Soup
How much of a fixed soup can replicators hold when some of their copies come out garbled?A fixed soup of 24 programs on a grid of opcode cells. Programs that bank enough energy become replicators and overwrite their neighbours with copies; by tick 150 most of the soup is replicators.