What is an example of a structural adaptation?

The streamlined shape of a fish is a clear example of a structural adaptation because it refers to a physical feature that has evolved to enhance the fish's ability to move efficiently through water. This adaptation minimizes resistance and allows for quicker swimming, which is crucial for escaping predators, chasing prey, and navigating through aquatic environments. Structural adaptations are generally specific anatomical features that directly impact an organism's survival and reproductive success. In this case, the shape aids in locomotion, demonstrating how physical traits are tailored to meet the needs of the organism's environment.

The other choices represent different types of adaptations. For instance, migration patterns are behavioral adaptations related to survival strategies rather than physical characteristics. Similarly, a dog's ability to learn commands showcases behavioral learning, which involves cognitive processes rather than structural features. Lastly, a plant's ability to grow in shade pertains to its physiological adaptability to environmental conditions, rather than a structural trait.