[Campbell Biology P.787] Which statement accurately compares contour feathers and downy feat... | Practice Question

Which statement accurately compares contour feathers and downy feathers in birds?

  • A: Contour feathers have hooks on their barbules for rigidity, while downy feathers lack hooks and provide insulation.
  • B: Both contour and downy feathers are stiff and primarily contribute to aerodynamic shape.
  • C: Downy feathers have a central air-filled shaft, but contour feathers do not.
  • D: Contour feathers are mainly for insulation, while downy feathers are for flight.

Explanation

The text states that 'Contour feathers are stiff and contribute to the aerodynamic shapes of the wings and body. Their barbules have hooks that cling to barbules on neighboring barbs.' It also says, 'Downy feathers lack hooks, and the free-form arrangement of their barbs produces a fluffiness that provides insulation by trapping air.' Therefore, option A accurately describes the differences and functions.