Spatial memory and orientation strategies in the elasmobranch Potamotrygon motoro.
We investigated whether juvenile freshwater stingrays (Potamotrygon motoro) can solve spatial tasks by constructing a cognitive map of their environment. Two experimental conditions were run: allocentric and ego-allocentric. Rays were trained to locate food within a four-arm maze placed in a room with visual spatial cues. The feeding location (goal) within the maze (room) remained constant while the starting position varied for the allocentrically but not for the ego-allocentrically trained group. After training, all rays solved the experimental tasks; however, different orientation strategies were used within and between groups. Allocentrically trained rays reached the goal via novel routes starting from unfamiliar locations, while ego-allocentrically trained rays primarily solved the task on the basis of an egocentric turn response. Our data suggest that P. motoro orients by constructing a visual cognitive map of its environment, but also uses egocentric and/or other orientation strategies alone or in combination for spatial orientation, a choice which may be governed by the complexity of the problem. We conclude that spatial memory functions are a general feature of the vertebrate brain.
Schluessel
Vera
V
Institute of Zoology, Rheinische Friedrich-Wilhelm-University Bonn, 53111 Bonn, Germany. v.schluessel@uq.edu.au
Bleckmann
Horst
H
D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D003213:Conditioning, Psychological / Q000502:physiology; D005247:Feeding Behavior / Q000502:physiology; D018782:Maze Learning / Q000502:physiology; D008568:Memory / Q000502:physiology*; D009949:Orientation / Q000502:physiology*; D012860:Skates, Fish / Q000502:physiology*; D013028:Space Perception / Q000502:physiology*