Eye evolution and its functional basis.
Eye evolution and its functional basis.
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DOI：
10.1017/s0952523813000035
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发表时间：
2013-03
影响因子：
1.9
通讯作者：
Nilsson, Dan-E
中科院分区：
文献类型：
--
作者：
Nilsson, Dan-E
眼睛的进化是由视觉引导行为的进化所驱动的。越来越苛刻的行为的积累不断提高了对感光器官的性能要求。从非定向光接受开始，我论证了一个进化序列，从定向光接受，低分辨率视觉，最后是高分辨率视觉。对这四种感官任务的物理需求的计算表明，它们与眼睛进化的重大创新相关，因此可以作为眼睛进化功能分析的相关分类。结合现有的分子和形态学数据，功能分析表明，urbilateria具有一套简单的横纹肌和睫状体受体，用于定向光接受，器官复制、位置转移和功能转移解释了现存动物的眼睛和光感受器的不同模式。分析还表明，在最后的双侧动物共同祖先之前，定向光接受至少独立进化了两次，并且在不同的双侧动物和刺胞动物群体中独立进化了几次，形成了真正的视觉。这种情况与pax基因在不同动物群体眼睛发育中的表达是一致的。从第一个视蛋白到高分辨率视力的整个过程花了大约1.7亿年，在大约5.3亿年前寒武纪开始时基本完成。从阴影探测器到多方向光感受器的进化进一步导致双壳类动物、扇虫和石鳖的眼睛进化。
Eye evolution is driven by the evolution of visually guided behavior. Accumulation of gradually more demanding behaviors have continuously increased the performance requirements on the photoreceptor organs. Starting with nondirectional photoreception, I argue for an evolutionary sequence continuing with directional photoreception, low-resolution vision, and finally, high-resolution vision. Calculations of the physical requirements for these four sensory tasks show that they correlate with major innovations in eye evolution and thus work as a relevant classification for a functional analysis of eye evolution. Together with existing molecular and morphological data, the functional analysis suggests that urbilateria had a simple set of rhabdomeric and ciliary receptors used for directional photoreception, and that organ duplications, positional shifts and functional shifts account for the diverse patterns of eyes and photoreceptors seen in extant animals. The analysis also suggests that directional photoreception evolved independently at least twice before the last common ancestor of bilateria and proceeded several times independently to true vision in different bilaterian and cnidarian groups. This scenario is compatible with Pax-gene expression in eye development in the different animal groups. The whole process from the first opsin to high-resolution vision took about 170 million years and was largely completed by the onset of the Cambrian, about 530 million years ago. Evolution from shadow detectors to multiple directional photoreceptors has further led to secondary cases of eye evolution in bivalves, fan worms, and chitons.