Undergraduate Research Symposium

Laterality is the preferential use of one side of the body to accomplish a task. One form of lateralization observed across taxa is the differential use of the left and right visual field. Among species that possess a left and right monocular visual field, previous research has shown a preference for using each eye to attend to different tasks. Most frequently it appears that visually lateralized animals will use their right eye to search for food while using their left eye to be vigilant for predators. Feeding and predator laterality have been observed in birds, reptiles, mammals, and some amphibian species. Evidence of feeding laterality in an amphibian species would add support to the body of evidence that suggests an early origin of lateralization in a common ancestor of vertebrates. This research aims to assert the presence or absence of lateralized feeding behaviors in tiger salamanders (Ambystoma tigrinum). To test for feeding lateralization a lab population of tiger salamanders were exposed to a visual stimulus in the form of a high value food item, a cricket, in both the right and left visual field. The intensity of their response to the visual stimulus was recorded and then the data for right and left side responses were compared. The data suggest a trend toward stronger feeding responses when the cricket was in the right visual field, however further analysis is needed to establish whether a significant side bias exists. These results are consistent with an early evolutionary origin of visual lateralization.