| Abstract: | We studied the capacity of seven Alsatian dogs to use a short cut in experiments carried out in a large (3-ha) meadow. The animals' task was to find meat hidden at two points (A and B) when released from a third (D). The dogs had each been taken previously on a lead to the two baited points by a different path that led indirectly from A to B via D (line segment AD = 24 m; DB = 40 m). The experiment was carried out in two different fields, one nearly homogeneous (covered mainly in thyme), and the other heterogeneous, containing visual features such as bushes, puddles and trails. In 96% of the 224 trials, the animals took a reasonably good short cut between the baited points rather than return to the start. The animals took the shortest possible path—a straight line directly from A to B—more frequently in the homogeneous than in the heterogeneous field. In the heterogeneous field, the animals had a greater tendency to use an “inside short cut”, heading for a point that intersected the path from the start to the second baited point rather than going directly to the point or returning to the start. The trials in which the shortest path was taken suggest that dogs are capable of evaluating along a continuum the direction of an invisible goal by integrating motor and sensory cues obtained during an early but indirect visit to the same goal. Some hypotheses are presented concerning the use of the inside short cut in this experiment, especially in an heterogeneous field. |
