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

白昼长度和其他光周期线索调节着浅水海洋栖息地中许多动物的繁殖。这些线索对海洋的深度有多重要还没有被研究过，但我们知道，许多深海和深海无脊椎动物也有季节性繁殖。这些物种的季节性繁殖与许多潜在的环境信号有关，包括营养物质的季节性流动，但对任何深海无脊椎动物来说，引导季节性繁殖周期的实际线索尚未进行实验研究。杨博士将利用潜水器测试两个可能控制生活在热带海洋斜坡上的深海棘足类动物繁殖的潜在因素：大型植物碎屑的季节性通量，以及极低光照强度下的日长周期。他还将研究食物供应、生长、繁殖力和繁殖时间之间的关系，使用在海底围栏中操纵食物的原位实验。

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.