A duck can't walk without bobbing its head - NSSB

A duck can’t walk without bobbing its head

Photo courtesy: Pritam B. Debnath

Birds bob their heads to improve their depth perception. Since most birds have eyes that are placed more on the sides, rather than the fronts, of their heads, much of their vision is monocular. Bobbing their heads back and forth helps them determine the relative distances of objects in their field of view.

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