Question

which environmental factor could lead to a decrease in genetic variation in a population of tuna?
○ an increase in food availability
○ an increase in pollution
○ a decrease in tuna fishing
○ a decrease in tuna predators

Explanation:

To determine which environmental factor decreases genetic variation in tuna:

• An increase in food availability (first option) would likely support population growth and diversity, not decrease variation.
• An increase in pollution (second option) can harm tuna, causing mortality of individuals with certain genetic traits. This reduces the gene pool, decreasing genetic variation.
• A decrease in tuna fishing (third option) or a decrease in tuna predators (fourth option) would typically allow the population to grow, which generally increases or maintains genetic variation.

Answer:

B. an increase in pollution