Final answer:
Population variation refers to the observation of variation in inherited traits within a population.
Step-by-step explanation:
Population variation refers to the observation that many inherited traits display variation within a population. This variation can be seen in the distribution of genotypes or phenotypes among individuals in a population.
For example, Mendel's pea plants displayed variation in traits such as flower color and seed shape, with some plants being homozygous dominant, heterozygous, or homozygous recessive for these traits. Similarly, domestic dogs display variation in fur colors and patterns.