Question

In the natural selection simulation, why does the r allele persist in the population when we set the fitness of rr individuals to 0? What would happen if selection was less extreme?

Answer 1

In the natural selection simulation, the r allele persists in the population due to the potential presence of carriers of beneficial alleles among rr individuals, allowing the r allele to be passed on to offspring. If selection was less extreme, the r allele may persist in the population at a lower frequency.

Step-by-step explanation:

In the natural selection simulation, the r allele persists in the population even when the fitness of rr individuals is set to 0 because natural selection acts on the phenotype. If individuals with the rr genotype have a fitness of 0, they will not survive to reproduce and pass on their alleles, including the r allele. However, if individuals with the rr genotype are carriers of another beneficial allele, they can still pass on the r allele to their offspring, contributing to its persistence in the population.

If selection was less extreme, meaning that the fitness of rr individuals is not reduced to 0 but rather reduced to a lower value, the r allele may persist in the population at a lower frequency. This is because even though individuals with the rr genotype may have reduced fitness, they can still survive and reproduce to some extent, allowing the r allele to be passed on to future generations.