biology / Evolution & Ecology / free

Population Genetics

Track how variation and selection reshape a population over generations.

Follow the mechanism1 / 3

A gene pool contains variation. Individuals contribute allele copies to a shared population, so the starting frequency records variation that can be passed to the next generation.

allele-frequency changeselection raises A · generation 10

Focus the idea

A allele71.9%

change+29.9%

heterozygosity40.4%

population80

Starting A allele 42%Selection for A +24%Population size 80Generations 10

Selection favors A, so its expected frequency rises when A is heritable. The actual path can wobble around that expectation.

This is a diploid Wright–Fisher teaching model: each generation draws 2N allele copies at random after selection, so drift is unbiased and can fix or lose an allele in a small population. The random draws are seeded, so the same settings replay the same history until you resample. Genotype bars assume random mating (Hardy–Weinberg). Real populations add mutation, migration, non-random mating, changing fitness, and demographic history.

04 / PRACTICE

Make the biology yours.

0 / 3 checked

Answer from the model, then use the explanation to connect the visual mechanism to the biological rule.

CHECK 1 / 3

Population Genetics

Make the biology yours.

What does allele frequency count?