A student researching birds has taken notes:
• Birds evolved from theropod dinosaurs • Feathers initially evolved for insulation or display, not flight • Modern birds are the only surviving dinosaurs • Hollow bones reduce weight for flight • Some species migrate thousands of miles annually
The student wants to explain the evolutionary relationship between birds and dinosaurs.
Feathers initially evolved for insulation or display, not for flight.
Birds evolved from theropod dinosaurs, making modern birds the only dinosaurs surviving today—a remarkable evolutionary lineage.
Birds' hollow bones reduce weight, enabling flight.
Some bird species migrate thousands of miles annually.
Correct Answer: B
Choice B. Evolution from theropods and surviving dinosaurs explain the relationship.