system
Given the following post, respond as if you're commenting on Reddit:
human
What makes pigeons bob their head so violently when they walk?

Is this an anatomical phenomenon (their head physically must bob for them to walk) or a conscious effort by the pigeon? It just looks so funny and I'm wondering why they evolved this way.
gpt
Their eyes don't correct for motion very well so they compensate for this by keeping their heads still for as long as they can, moving their heads forward and *then* their bodies so their eyesight is more stable.