Cohen Jonathan H, Frank Tamara M
Department of Visual Ecology, Division of Marine Science, Harbor Branch Oceanographic Institution, 5600 US 1 North, Fort Pierce, Florida 34946, USA.
Biol Bull. 2006 Oct;211(2):140-8. doi: 10.2307/4134588.
Although the visual systems of animals living in the cold, dark water of the deep sea have been investigated for some time, little is known about vision in animals inhabiting polar oceans, where temperatures are even colder and irradiance fluctuates dramatically with ice cover and season. Physiology of the compound eye of the amphipod Abyssorchomene plebs (Gammaridea: Lysianassoidea), a common Antarctic benthic scavenger, was studied electrophysiologically by electroretinography. A. plebs has a monochromatic visual system with a spectral sensitivity maximum at 487 nm, and higher sensitivity at ultraviolet wavelengths than predicted by a visual pigment template. While irradiance sensitivity determined from V/log I curves is comparable to that of mesopelagic crustaceans, temporal resolution calculated from response waveform dynamics and as determined by critical flicker fusion frequency suggest that the A. plebs eye is slower than that of crustaceans from the deep sea. A. plebs photoreceptors are physiologically adapted for a slow lifestyle in a low-light environment, where maximizing photon capture occurs at the expense of detecting fast events in the visual scene.
尽管生活在深海寒冷、黑暗水域中的动物视觉系统已被研究了一段时间，但对于栖息在极地海洋中的动物的视觉情况却知之甚少，因为极地海洋温度更低，光照强度会随着冰层覆盖和季节变化而剧烈波动。通过视网膜电图对南极常见底栖食腐动物——双尾目深渊长额虾（Gammaridea: Lysianassoidea）复眼的生理机能进行了电生理学研究。深渊长额虾具有单色视觉系统，其光谱敏感度在487纳米处达到最大值，并且在紫外波长下的敏感度高于视觉色素模板预测的敏感度。虽然从V/log I曲线确定的光照敏感度与中层甲壳类动物相当，但根据响应波形动力学计算并由临界闪烁融合频率确定的时间分辨率表明，深渊长额虾的眼睛比深海甲壳类动物的眼睛反应速度慢。深渊长额虾的光感受器在生理上适应了低光照环境下的缓慢生活方式，在这种环境中，以牺牲检测视觉场景中的快速事件为代价来实现光子捕获最大化。
