Removal of eyes in early larval stages alters the response of the clawed toad, Xenopus laevis, to surface waves.

The clawed toad, Xenopus laevis, responds to surface waves with a very accurate orienting reaction towards the source of the wave. The importance of visual experience during larval development for this orienting reaction guided by the lateral line was investigated by testing the responses in postmetamorphic animals deprived of vision from an early larval stage by enucleation or rearing in darkness. Control animals were enucleated after metamorphosis. The results show that the orienting response in animals enucleated as larvae is less accurate; the slope of the regression of the turning angle on stimulus angle is only 0.58, compared to 0.82 for the control animals. It is hypothesized that the likely location for the interaction between the visual system and the lateral line is the tectum opticum.