Entrainment of Seasonal Reproductive Cycles in Echinoderms Living Below the Euphotic Zone

日长和其他光周期信号控制着许多动物在浅水海洋栖息地的繁殖。这种线索在海洋中的重要深度还没有被调查，但我们知道，许多深海和半深海无脊椎动物也会季节性繁殖。这些物种的季节性繁殖与许多潜在的环境信号相关，包括季节性营养物质的流动，但对任何深海无脊椎动物来说，涉及季节性繁殖周期的实际线索尚未得到实验研究。使用潜水器，杨博士将测试两个可能控制生活在热带海域斜坡上的半深海棘球藻类繁殖的因素：大型植物碎屑的季节性流动，以及极低光照强度下的日长周期。他还将利用在海底封闭环境中操纵食物的现场实验，研究食物供应、生长、繁殖力和繁殖时机之间的关系。

Daylength and other photoperiodic cues regulate reproduction of many animals in shallow-water marine habitats. The depth to which such cues are important in the sea has not been investigated, but it is known that numerous deep-sea and bathyal invertebrates also reproduce seasonally. Seasonal reproduction in these species correlates with numerous potential environmental signals, including seasonal flux of nutrients, but the actual cues that entrain seasonal reproductive cycles have not been investigated experimentally for any deep-sea invertebrate. Using submersibles, Dr. Young will test two potential factors that could control reproduction in bathyal echinoids living on the slope in tropical seas: seasonal flux of macrophytic detritus, and daylength cycles at very low light intensities. He will also investigate the relationship between food supply, growth, fecundity, and timing of reproduction using in situ experiments in which food is manipulated in enclosures on the sea floor.