Final answer:
Yes, there is evidence of selection for defensive adaptations in mollusc populations exposed to predators.
Step-by-step explanation:
Yes, there is evidence of selection for defensive adaptations in mollusc populations exposed to predators. Predation and predator avoidance are strong selective agents, and any heritable character that allows a prey individual to better evade its predators will be represented in greater numbers in later generations. Traits that allow a predator to more efficiently locate and capture its prey will also lead to an increase in the commonness of the trait within the population. Examples of defensive adaptations in molluscs include mechanical defenses like shells, chemical defenses like toxins, and behavioral defenses like burrowing or camouflage.