A Pigeon's Gait

[Champagne]

Why do pigeons bob their heads when they walk?

[priveet]

This bird bobs to maintain its balance. A pigeon's legs are pretty far forward on its body. If it didn't pull its head back when it steps forward, most of its weight would be momentarily concentrated up front and it could fall flat on its beak. Once it's balanced from bobbing its head back, the pigeon can then bob forward while bringing up the other foot to complete the step.

[OnlyMe]

I thought it was because they were all trying to imitate Norman Collier?

[robber1]

"OnlyMe" took the words out of my mouth.

[jl]

Head-bobbing is a common trait among ground birds like pigeons, pheasants, partridges, and chickens. Ornithologists call it the "optokinetic response," and it seems to help the birds' vision. Remember that a pigeon's eyes are set on the sides of its head, so that when it's walking around, the world sort of sails by in a confusing blur, like landscape viewed from a moving train. The optokinetic response appears to compensate for this. Next time you're down at St. Mark's Plaza, take a look: The pigeon has a kind of inchworm gait. It jerks its head forward, then brings its body to meet it, then jerks its head forward again. The net result: The bird gets a series of fixed snapshot images, rather than a long, continuous blurry one. (A twirling ballerina uses a similar strategy, keeping her head aimed at a fixed point while her body rotates.) Back in the late seventies, Barrie J. Frost, a visual neuroscientist at Queens University in Kingston, Ontario, put pigeons on a tiny treadmill. They walked, but they didn't move relative to their environment-and they stopped bobbing. Draw your own conclusions; to me it's scientific proof that if you're going to get anywhere, you have to stick your neck out.