Adaptation of Photoreceptor Physiology to Life History Stage in Ontogenetically Migrating Deep-Sea Crustaceans

许多海洋物种有一个难以处理的问题，因为它们在一生中生活在截然不同的光照环境中。 这些物种是个体发育的迁徙者，因为年轻的青少年阶段生活在相对明亮的浅水沃茨，而年长的成年阶段可能生活在1000米深，那里几乎没有光。 事实上，我们对这两个生命史阶段如何适应这些截然不同的光环境一无所知。 这是一个拥有一只在明亮和昏暗的光线下都能工作的眼睛的问题，但在任何一种情况下都不是最佳视觉的最佳设计吗？ 或者，是否存在某种机制，可以在不到一年的时间内，将一只在明亮光线下功能良好的眼睛转换为在非常昏暗的光线下功能良好的眼睛？ 这项建议旨在研究是否深生活的成年人比浅生活的青少年对光更敏感，以及在各种甲壳类物种中产生这些敏感性差异的机制，如果它们存在的话。 这将通过使用生理学，分子和组织学技术相结合来检查他们眼睛的各种特征，即他们对光线的敏感性，他们的结构和光学，以及他们的视觉色素。 这些甲壳类物种中有许多是支持主要商业渔业的海洋食物网的主要组成部分，了解它们是否以及如何适应不同的光环境对于模拟光环境变化（例如污染导致的水透明度变化）可能对其分布模式产生的影响至关重要。 此外，还将研究热液喷口虾巨大的背眼。 迄今为止，已收集到的所有热液喷口虾的背眼都显示出严重的光损伤迹象。 这引起了人们的关注，即这些眼睛可能是非常敏感的结构，正在被光破坏，并导致人们认为，在大量研究的喷口地点，大多数喷口虾由于反复暴露在水下和潜水器中而永久失明。 不幸的是，所有被检查的虾都是在非常明亮的人造光下收集的，并且不可能确定所有的光损伤是否发生在收集过程中，或者是由于过去暴露于人造光。 通过新设计的收集技术，可以在不暴露于光的情况下收集这些物种，该提案旨在研究从未暴露于光的背眼的敏感性，以及在实验室中反复暴露于泛光灯照明的累积效应。 这项研究将提供数据，以解决是否需要指定禁猎区类型的非访问区，以研究致盲的生态系统中的大多数移动的生物体的生态影响的问题。

A number of marine species have a difficult problem to deal with, in that they live in vastly different light environments during the course of their lifetimes. These species are ontogenetic migrators, in that the young juveniles stages live in relatively brightly lit shallow waters, while the older adult stages may live 1000 m deeper, where there is very little light. Virtually nothing is known about how these two life history stages adapt to these dramatically different light environments. Is it a matter of possessing an eye that works in both bright and dim light, but isn't really the best design for optimal vision under either condition? Or are there mechanisms in place that allow for the conversion of an eye designed to function well in bright light to one that functions well in very dim light, over a timeframe of less than a year? This proposal seeks to examine whether deep-living adults are substantially more sensitive to light than shallow-living juveniles, as well as the mechanisms involved in producing these sensitivity differences, if they exist, in a variety of crustacean species. This will be done by using combination of physiological, molecular and histological techniques to examine various characteristics of their eyes, namely their sensitivity to light, their structure and optics, and their visual pigments. Many of these crustacean species are major components of the oceanic food webs that support the major commercial fisheries, and understanding whether and how they adapt to different light environments is critical to modeling what effect a change in their light environment (such as a change in water clarity due to pollution) may have on their distribution patterns. In addition, the enormous dorsal eye of hydrothermal vent shrimp will be examined. To date, the dorsal eyes of all the hydrothermal vent shrimp that have been collected show signs of significant light damage. This has given rise to the concern that these eyes may be remarkably sensitive structures that are being destroyed by light, and led to the suggestion that a majority of the vent shrimp at heavily studied vent sites are being permanently blinded by repeated exposure to ROV and submersible. Unfortunately, all the shrimp that have been examined have been collected under extremely bright artificial lights, and it has been impossible to determine whether all the light damage occurred during the collection, or was due to some past exposure to artificial lights as well. With newly designed collecting techniques that will allow collection of these species without exposure to light, this proposal seeks to study the sensitivity of a dorsal eye that has never been exposed to light, as well as the cumulative effects of repeated exposure to floodlight illumination in the laboratory. This research will provide data to address the issue of whether sanctuary type no-visit zones need to be designated in order to study the ecological impact of blinding a majority of the mobile organisms in an ecosystem.