1. 1.

    Head-bobbing of pigeons during walking and landing was studied using high-speed motion photography.

  2. 2.

    The analysis of film records indicated that head-bobbing whilst walking consists of two phases: one where the head is ‘locked’ in space but moves backward relative to its forward moving body; and another where it is thrust rapidly forward to a new position.

  3. 3.

    The fact that head-bobbing is abolished when pigeons walk on a treadmill suggests it is primarily a visual response rather than an equilibratory response.

  4. 4.

    Data are presented which show that stabilization during the ‘lock’ phase allows a small degree of slippage which is the probable source of error signals for compensatory head movements.

  5. 5.

    The head-bobbing that appears to occur during landing is shown to be illusory.

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