Neutral polygenic trait evolution in landscapes
This applet shows the neutral evolution of three polygenic traits in a two-dimensional landscape. Each trait is influenced by ten additive biallelic loci. The traits are represented by shades of the colours red, green and blue. Higher trait values appear as brighter colours. The graph shows the frequency of individuals with each possible value for each trait. Initially, all alleles are random. Over time, recombination removes some variations by chance from local areas, leading to local spatial correlations in colour. If there is no mutation, all variation is eventually lost, but because the loss of alleles through drift is very slow, even a small mutation rate is sufficient to maintain the traits in a varying state.