Natural selection weeds out harmful genes, yet they never fully vanish. Watch selection and mutation fight to a standstill over the generations.
Mutation–Selection BalanceLive
evolution of an allele
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Selection pushes a favorable allele toward fixation, while mutation keeps feeding the alternative back in. The two forces settle at a mutation–selection balance — which is why harmful alleles never fully disappear from a population. Educational tool.
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How it works
Selection changes allele frequencies by favoring fitter genotypes, while recurrent mutation keeps reintroducing variants. The two reach a mutation–selection balance where a deleterious allele persists at a low, steady frequency — a core result of population genetics. Educational tool.
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Is this mutation selection balance tool really free?▾
Yes. Mutation–Selection Balance runs entirely in your browser using your device's own compute, so local use is free forever. You only pay Compute Tokens if you scale a job to the cloud.
Do I need to install anything?▾
No. Everything runs client-side in a modern browser — no downloads, no license, no account required to start.
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How accurate are the results?▾
The solver uses established numerical methods, but results are for research and educational purposes and should be validated against experiment or professional review before you rely on them.