| Abstract: | Eating rats dodge conspecifics, who are trying to steal their food, by making a somewhat stereotyped 180° turn and step movement to block the robber's approach. This experiment examined the effect of food features on the form and vigor of the dodging movement. Dodge probability and its amplitude were measured as a function of food size, elapsed eating time, food hardness, and the way in which food theft was attempted. Under all conditions dodge probability and its amplitude were directly related to the time necessary to complete eating. Thus, rats estimated the time required to complete eating and adjusted the size of their evasive movements to gain this time. The results show that although dodging has the appearance of a fixed-action pattern, it is influenced by cognitive processes that may be similar to those that direct other aspects of foraging behavior. © 1994 Wiley-Liss, Inc. |
