Further studies were made of the simultaneous comparison mechanism used by hatchling green turtles, Chelonia mydas, in sea-finding behaviour. The aim was to learn if visual inputs from different directions, stimulating different parts of the retina, had the same effects on orientation. To do this goggles were designed that permitted occlusion of parts of the visual field. Wearing goggles did not in itself affect orientation. When the nasal visual field for one eye and the temporal field for the other eye were covered, turtles circled consistently in the direction of the eye with the nasal occlusion. The total numbers of circles made in a given time by such turtles were not significantly different from those made by animals with simple unilateral blindfolds. Covering the temporal field of one eye resulted in some, though not all, turtles turning contralateral to that eye, provided the other eye was totally covered. On the whole the data were consistent with the idea that inputs in the nasal field are associated with contralateral turning and those in the temporal field with ipsilateral turning. Some complications to this interpretation are also discussed. However, the results demonstrate unequivocally that inputs from different directions contribute differently to sea-finding orientation of green turtles.
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| All Time | Past Year | Past 30 Days | |
|---|---|---|---|
| Abstract Views | 118 | 32 | 2 |
| Full Text Views | 125 | 3 | 1 |
| PDF Views & Downloads | 17 | 4 | 2 |
Further studies were made of the simultaneous comparison mechanism used by hatchling green turtles, Chelonia mydas, in sea-finding behaviour. The aim was to learn if visual inputs from different directions, stimulating different parts of the retina, had the same effects on orientation. To do this goggles were designed that permitted occlusion of parts of the visual field. Wearing goggles did not in itself affect orientation. When the nasal visual field for one eye and the temporal field for the other eye were covered, turtles circled consistently in the direction of the eye with the nasal occlusion. The total numbers of circles made in a given time by such turtles were not significantly different from those made by animals with simple unilateral blindfolds. Covering the temporal field of one eye resulted in some, though not all, turtles turning contralateral to that eye, provided the other eye was totally covered. On the whole the data were consistent with the idea that inputs in the nasal field are associated with contralateral turning and those in the temporal field with ipsilateral turning. Some complications to this interpretation are also discussed. However, the results demonstrate unequivocally that inputs from different directions contribute differently to sea-finding orientation of green turtles.
| All Time | Past Year | Past 30 Days | |
|---|---|---|---|
| Abstract Views | 118 | 32 | 2 |
| Full Text Views | 125 | 3 | 1 |
| PDF Views & Downloads | 17 | 4 | 2 |