Figure 3.

Paired foraging in the maze, but not in the cage, influenced running (Experiment 1). (A) Chicks were divided into four experimental groups according to 2 × 2 block placement. “In the maze” means chicks were single or paired in the I-shaped maze during the tests, whereas “in the cage” means that chicks foraged in single or paired condition in their home cage. Note that chicks were housed in pairs in all conditions except foraging. (B) Means (±SEM) of running distance (upper) and synchrony index (lower) during feeding time (ca. 8 min) are plotted against the day of the experiment. Open and filled symbols denote paired and single foraging in the maze, whereas circles and rhombi denote paired and single foraging in the cage, respectively, in this and the following figures.