Question 48

Some birds have long, curved beaks that they use to extract nectar from flowers and some birds have webbed feet that allow them to swim and dive efficiently in water.

Structural adaptations are physical features that have evolved to help an organism survive in its environment. The examples provided highlight specific physical traits that enhance the functional capabilities of certain birds.

A) Some birds travel in large migratory flocks that may discourage attacks by predators.

This option describes a behavioral adaptation rather than a structural one. While migrating in flocks can provide safety from predators, it does not involve a physical change or feature of the birds themselves.

B) Some birds have long, curved beaks that they use to extract nectar from flowers.

This option is a clear example of a structural adaptation. The long, curved beak is a physical characteristic that enables birds to access nectar, which is essential for their feeding and survival, demonstrating how form is adapted to function.

C) Some birds are active mainly at night, which reduces competition for limited resources.

Similar to option A, this describes a behavioral adaptation. The nocturnal activity reduces competition but does not involve any physical traits of the birds, thus not qualifying as a structural adaptation.

D) Some birds have webbed feet that allow them to swim and dive efficiently in water.

This option is another example of a structural adaptation. The webbed feet are a physical trait that enhances the bird's ability to navigate and thrive in aquatic environments, illustrating a direct adaptation to their habitat.

Conclusion

Both options B and D exemplify structural adaptations, as they involve physical characteristics that improve the birds' abilities to find food and survive in their environments. Options A and C, while relevant to survival strategies, focus on behaviors rather than physical traits, thus failing to meet the criteria for structural adaptations.