Which experimental approach involves rearing marine and freshwater populations in a common environment?

Which experimental approach involves rearing marine and freshwater populations in a common environment?

• A. Common garden experiment
• B. Reciprocal transplant study
• C. Crossbreeding trial
• D. Controlled breeding program

Answer: (A)

Raising marine and freshwater populations in the same environment is a common garden approach. The goal is to control environmental conditions so any differences you observe in traits come from genetics rather than where the fish were living. If the two populations still show different traits—like armor plating, body shape, or specific behaviors—when they’re all raised in identical conditions, that indicates genetic differences underlie those traits. If the differences disappear in the common environment, it suggests environment was driving the variation instead. This design specifically isolates heredity from environment. By contrast, a reciprocal transplant study would test how each population performs in the other’s natural habitat to detect local adaptation; crossbreeding trials focus on how traits are inherited through mating, and a controlled breeding program is about selecting traits for breeding rather than comparing populations in a uniform setting.

Raising marine and freshwater populations in the same environment is a common garden approach. The goal is to control environmental conditions so any differences you observe in traits come from genetics rather than where the fish were living. If the two populations still show different traits—like armor plating, body shape, or specific behaviors—when they’re all raised in identical conditions, that indicates genetic differences underlie those traits. If the differences disappear in the common environment, it suggests environment was driving the variation instead.

This design specifically isolates heredity from environment. By contrast, a reciprocal transplant study would test how each population performs in the other’s natural habitat to detect local adaptation; crossbreeding trials focus on how traits are inherited through mating, and a controlled breeding program is about selecting traits for breeding rather than comparing populations in a uniform setting.