They should separate pure lines (red fan-shaped tails) to cross them with other phenotypes and then observe phenotypic proportion in the offspring. It is Mendelian genetics.
Mendelian genetics refers to the process of observing the phenotypic proportions from a given genetic cross.
Mendelian genetics is always associated with a genetic process known as complete dominance.
Complete dominance occurs when the recessive allele is completely masked in heterozygous individuals.
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