Collaborative Research: Energy Sources for Reproduction and Development in a Cold-seep Mixotrophic Mussel

合作研究：冷泉混合营养贻贝繁殖和发育的能源

• 批准号: 0118946
• 负责人: Stephen Macko
• 金额: $ 15.06万
• 依托单位: University of Virginia Main Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-01-01 至 2006-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0118946&HistoricalAwards=false
• 关键词: Collaborative; Research; Energy; Sources; Reproduction

Heterotrophic deep-sea animals require a downward flux of material in order to survive and reproduce, whereas animals with chemoautotrophic symbionts at hydrothermal vents or cold seeps should theoretically be capable of producing gametes more-or-less continuously without the benefit of surface-derived detritus. Mixotrophic mussels at cold seeps are intermediate between these two situations. They can grow and survive using only methane or sulfide as an energy source, but are also capable of filter-feeding on detrital particles or plankton in the benthic boundary layer. Available evidence suggests that supplemental filtration on bacterioplankton may be necessary to provide sufficient nitrogen to the mussels. The cold-seep mussel Bathymodiolus childressi, which lives at methane seeps on the Louisiana slope, demonstrates periodic rather than continuous reproduction, a pattern not predicted by the commonly accepted paradigm that food limitation controls reproductive timing in the deep sea. Thus, mixotrophic mussels present a unique opportunity to investigate the role of detrital input in the control of gametogenic timing in the deep sea. Lipid biomarkers and compound specific stable isotopes will be used to determine if energy from surfacederived detritus is differentially partitioned between the gonads and somatic tissues of B. childressi. In the deep-sea megafauna, seasonal breeders virtually always produce feeding larvae, suggesting a possible mechanistic or evolutionary link between surface production and larval success. Crisp's rule, the prediction that animals with planktotrophic larvae will time their breeding to assure optimal nutrition for the larvae, is one such possible link. Crisp's Rule will be examined in this study by rearing the larvae of B. childressi in natural water collected at various depths.

异养深海动物需要向下流动的物质才能生存和繁殖，而在热液喷口或冷泉中具有化能自养共生体的动物理论上应该能够或多或少连续地产生配子，而无需表面衍生的碎屑的帮助。冷泉处的混合营养贻贝介于这两种情况之间。它们可以仅使用甲烷或硫化物作为能源来生长和生存，但也能够滤食底栖边界层中的碎屑颗粒或浮游生物。现有证据表明，可能需要对浮游细菌进行补充过滤，以便为贻贝提供足够的氮。生活在路易斯安那州斜坡甲烷渗漏处的冷泉贻贝Bathymodiolus childressi表现出周期性而不是连续的繁殖，这种模式没有被普遍接受的范式所预测，即食物限制控制深海的繁殖时间。因此，混合营养贻贝为研究碎屑输入在深海配子发生时间控制中的作用提供了独特的机会。脂质生物标志物和化合物特异性稳定同位素将用于确定来自表面的碎屑的能量在 B. childressi 的性腺和体细胞组织之间是否有差异分配。在深海巨型动物群中，季节性繁殖者几乎总是产生摄食幼虫，这表明表面生产和幼虫成功之间可能存在机械或进化联系。克里斯普规则，即具有浮游营养幼虫的动物将安排其繁殖时间以确保幼虫获得最佳营养的预测，就是这样一种可能的联系。本研究将通过在不同深度收集的天然水中饲养 B. childressi 幼虫来检验克里斯普法则。