Why can multiple alleles only be studied in populations?

Average annual precipitation and are the two major features that define the biomes on earth.

In pea plants, the allele for inflated pod seed, i, is dominant over the allele for constricted pod seed, i. the punnett square shows a cross for this trait. which offspring will be homozygous dominant

Which of the following explains why a tree is often used as a model to represent the principle of common descent