For traits that are repeatable across an animal's lifetime, such as litter size or milk yield, what is primarily used to predict phenotype?

For traits that are repeatable across an animal's lifetime, such as litter size or milk yield, what is primarily used to predict phenotype?

• A. Environment
• B. Genetics
• C. Random variation
• D. Nutrition

Answer: (B)

Genetics is the main predictor here. For traits that are measured across an animal’s life, the additive genetic component—the animal’s genetic merit or breeding value—sum up to determine how much of the repeated performance is passed to offspring. While environment, nutrition, and random variation influence the actual numbers you observe, the portion of performance tied to genetics is relatively stable across time and environments. Repeated records help separate permanent environmental effects from genetics, sharpening the accuracy of genetic merit estimates used to predict future phenotype. So, the best predictor of lifetime performance for these traits is the animal’s genetic makeup.

Genetics is the main predictor here. For traits that are measured across an animal’s life, the additive genetic component—the animal’s genetic merit or breeding value—sum up to determine how much of the repeated performance is passed to offspring. While environment, nutrition, and random variation influence the actual numbers you observe, the portion of performance tied to genetics is relatively stable across time and environments. Repeated records help separate permanent environmental effects from genetics, sharpening the accuracy of genetic merit estimates used to predict future phenotype. So, the best predictor of lifetime performance for these traits is the animal’s genetic makeup.