The jerky neck motions of a whooping crane looking for lunch keep its head still in space about half the time, probably helping the bird to spot food, a video study suggests.
When walking, cranes and many other birds thrust their heads forward, then let their bodies catch up. A Maryland research team now says that it has made the first measurements of a bird's natural head bobbing while hunting. The result fits the idea that head bobbing benefits a hunter, says Thomas Cronin of the University of Maryland, Baltimore County.
Scientists have theorized for decades that head bobbing has something to do with vision, explains Cronin. When a bird's head is still, images form on the retina without the blur of motion. So, the hypothesis goes, maximizing the stillness