Question

What is the advantage of a polygenic trait over a single gene trait?

Answer 1

Polygenic traits have several advantages over single gene traits, including a wide range of variation, resilience to environmental changes, and more opportunities for natural selection.

Step-by-step explanation:

Polygenic traits have several advantages over single-gene traits:

1. Polygenic traits show a wide range of variation in a population. For example, height, skin color, and weight can vary significantly among individuals. This allows for greater diversity within a species, which can be beneficial for survival and adaptation.
2. Polygenic traits are less affected by environmental factors compared to single-gene traits. While single-gene traits may have a binary expression (either present or absent), polygenic traits can have a continuum of phenotypes. This means that even if environmental conditions change, the range of phenotypes can still be maintained.
3. Polygenic traits provide more opportunities for natural selection. Since multiple genes contribute to the phenotype, natural selection can act on each gene individually, promoting the survival of individuals with advantageous combinations of alleles. This allows for the gradual shaping of a trait over generations.

Answer 2

Single gene traits: controlled by a single gene that has two alleles (ex: widow's peak) – only two phenotypes are possible – widow's peak or no widow's peak.Polygenic traits: controlled by two or more genes. Has 2 or more alleles. One polygenic trait can have many possible genotypes and phenotypes!