What findings would indicate polygenic control of armor traits?

What findings would indicate polygenic control of armor traits?

• A. Continuous variation in plate numbers across individuals and multiple genomic regions showing small-to-moderate effect sizes.
• B. Discrete, bimodal plate numbers with a single major-effect locus.
• C. No variation in plate numbers.
• D. Plate numbers controlled by a single gene.

Answer: (A)

Polygenic control shows up as continuous variation driven by many genes each contributing a small effect. In armor traits, you’d see plate numbers vary gradually across individuals, not settle into a few distinct categories. Supporting this, genome-wide studies would reveal multiple regions across the genome, each with small-to-moderate effect sizes, collectively shaping the trait. That combination—gradual, continuous variation and evidence of many loci with modest effects—is the hallmark of polygenic control. In contrast, a discrete bimodal pattern with one major locus would point to simple, single-gene control; no variation or variation from a single gene would not reflect polygenic architecture.

Polygenic control shows up as continuous variation driven by many genes each contributing a small effect. In armor traits, you’d see plate numbers vary gradually across individuals, not settle into a few distinct categories. Supporting this, genome-wide studies would reveal multiple regions across the genome, each with small-to-moderate effect sizes, collectively shaping the trait. That combination—gradual, continuous variation and evidence of many loci with modest effects—is the hallmark of polygenic control. In contrast, a discrete bimodal pattern with one major locus would point to simple, single-gene control; no variation or variation from a single gene would not reflect polygenic architecture.