Fig. 9. Visuo-motor guidance model. (A) Frontal landmark, symmetric response. (B) Lateral landmark, biased response. (C) Two black cylinders, symmetric response. (D) Cylinders of different color, biased response to green cylinder. Red arrows indicate hypothetical approach paths from the entry (black square) to the food hole (cross). Curved arrows indicate the strength with which landmarks are `pushed out' of each hemisphere by compensatory turning reactions. For example, in D, the thick green arrow indicates a strong (anti-clockwise) turning response for right-to-left movement of the green cylinder. For details, see text.