Jaeger R G, Hailman J P
J Comp Physiol Psychol. 1976 Oct;90(10):930-45. doi: 10.1037/h0077275.
Tadpoles of three species of anurans initially had a midspectrum ("green") preference in laboratory phototactic tests, which was shown experimentally to involve a form of true color vision in one species and probably in the other two as well. During development, the preference shifted to shorter wave-lengths (higher frequencies) until a short-wavelength ("blue") preference predominated in the pre- and postmetamorphic stages and in the adults of six species tested; color vision was involved in all of these stages. The green preference of young tadpoles is ecologically adaptive, in that it directs larvae to green plants that provide food or shelter. Tadpoles observed in a pond congregated heavily in vegetated areas rather than in open water. Spectroradiometric field measurements showed that pond illumination in vegetated areas had a more highly saturated yellow-green spectral dominance compared with a desaturated white illumination in open water. During all ontogenetic stages and as adults, the animals had a preference for high illuminance of white light, which correlates with the high illumination of their habitat. Microspectrophotometric data from Liebman and Entine suggested that the green rods are active receptors in tadpoles, making unlikely Muntz's hypothesis that the ontogenetic shift in spectral preferences is due to premetamorphic maturation of these receptors. However, the visual pigments of all five types of photoreceptors shifted from vitamin A2- to vitamin A1-based chromophores during ontogeny, and the resulting shift in spectral response of the receptors might be related to the spectral shift in phototactic preferences.
在实验室趋光性测试中，三种无尾两栖类动物的蝌蚪最初都偏好中光谱（“绿色”），实验表明，其中一个物种以及另外两个物种可能也涉及一种真正的色觉形式。在发育过程中，这种偏好转向较短波长（较高频率），直到在六个测试物种的变态前、变态后阶段以及成体中，短波长（“蓝色”）偏好占主导；所有这些阶段都涉及色觉。幼体蝌蚪对绿色的偏好具有生态适应性，因为它引导幼体游向提供食物或庇护所的绿色植物。在池塘中观察到的蝌蚪大量聚集在植被区域而非开阔水域。光谱辐射度野外测量表明，与开阔水域不饱和的白色光照相比，植被区域的池塘光照具有更高饱和度的黄绿色光谱优势。在所有个体发育阶段以及成年期，这些动物都偏好高亮度的白光，这与它们栖息地的高光照度相关。来自利布曼和恩廷的显微分光光度数据表明，绿色视杆细胞是蝌蚪中的活跃感受器，这使得蒙茨关于光谱偏好个体发育转变是由于这些感受器在变态前成熟的假设不太可能成立。然而，在个体发育过程中，所有五种光感受器的视觉色素都从基于维生素A2的发色团转变为基于维生素A1的发色团，感受器光谱响应的这种变化可能与趋光偏好的光谱变化有关。
