Abstract:
Early pioneering studies by Autrum on terrestrial arthropods first revealed that the visual systems of arthropods reflected their lifestyles and habitats. Subsequent studies have examined and confirmed Autrum\'s hypothesis that visual adaptions are driven by predator-prey interactions and activity cycles, with rapidly moving predatory diurnal species generally possessing better temporal resolution than slower moving nocturnal species. However, few studies have compared the vision between diurnal herbivores and nocturnal predators. In this study, the visual physiology of a nocturnal fast-moving predatory crab, the Atlantic ghost crab (Ocypode quadrata) and a diurnal herbivorous crab, the mangrove tree crab (Aratus pisonii), was examined. Spectral sensitivity, irradiance sensitivity and temporal resolution of the crabs were quantified using the electroretinogram (ERG), while the spatial resolution was calculated utilizing morphological methods. Both O. quadrata and A. pisonii had a single dark-adapted spectral sensitivity peak (494 and 499 nm, respectively) and chromatic adaptation had no effect on their spectral sensitivity, indicating that both species have monochromatic visual systems. The temporal resolution of O. quadrata was not significantly different from that of A. pisonii, but O. quadrata did possess a significantly greater spatial resolution and irradiance sensitivity. Both species possess an acute zone in the anterior region of their eyes. The data presented in this study will aid in the current understanding of the correlation between visual physiology and the life history of the animal.
摘要:
Autrum对陆地节肢动物的早期开创性研究首先表明,节肢动物的视觉系统反映了它们的生活方式和栖息地。随后的研究已经检查并证实了奥特鲁姆的假设,视觉适应是由捕食者/猎物的相互作用和活动周期驱动的,快速移动的捕食性昼夜物种通常比缓慢移动的夜间物种具有更好的时间分辨率。然而,很少有研究比较了昼夜食草动物和夜间食肉动物的视觉。在这项研究中,夜间快速移动的捕食蟹的视觉生理学,大西洋幽灵蟹(Ocypodequadrata),和一只昼夜食草蟹,红树林树蟹(Aratuspisonii),被检查过。光谱灵敏度,辐照度灵敏度,并使用视网膜电图(ERG)对螃蟹的时间分辨率进行定量,而空间分辨率是利用形态学方法计算的。O.quadrata和A.pisonii均具有单个暗适应光谱灵敏度峰(分别为494和499nm),并且色适应对其光谱灵敏度没有影响,表明这两个物种都有单色视觉系统。O.quadrata的时间分辨率与A.pisonii的时间分辨率没有显着差异,但是O.quadrata确实具有更大的空间分辨率和辐照度灵敏度。这两个物种在其眼睛的前部区域都有一个急性带。这项研究中提供的数据将有助于当前对视觉生理学与动物生活史之间相关性的理解。