Collaborative Research - Metazoan Life at Extreme Sulfide Concentrations: The ecology and evolution of Dorvilleidae at methane seeps

千摩尔H2S浓度和几乎没有氧气使得甲烷渗漏沉积物成为地球上最有毒的环境之一，然而后生动物的组合在这样的环境中仍然存在。在西北太平洋上坡的微生物席覆盖的渗漏中，这些组合几乎完全由多毛纲组成。在俄勒冈州和加利福尼亚州边缘的氧气最低带的渗漏处，pi已经确定了多达17种共存的多维蝇，其中包括一个属的10种。pi们假设，这个环节动物群体通过对低氧和高浓度硫化物的特殊耐受性，找到了一套它自己能够利用的生态位，结果在没有捕食者和竞争对手的情况下经历了进化释放。pi建议使用这种多维蝇组合作为模型系统，以研究后生动物群落如何在极端硫化物条件下进化和适应。通过将生态特征映射到系统发育框架中，pi将识别生态学，生理学，生活史和进化历史之间的相关性，从而有助于阐明极端压力下物种形成的机制。他们预计，多毛纲最终将为综合极端微生物的研究提供一个极好的后生动物模型。由加州卓越海洋科学教育中心（COSEE）促成的伙伴关系将使这些私人学院能够进行严格的教育和推广工作。新发现将被纳入目前由美国国家科学基金会资助的海洋研究所海底科学项目（ISE #0229063）的一部分。

Millimolar H2S concentrations and the near absence of oxygen make methane seep sediments one of the most toxic environments on earth, yet metazoan assemblages persist in such settings. In microbial-mat covered seeps on the upper slopes of the Pacific Northwest, these assemblages are comprised nearly exclusively of dorvilleid polychaetes. At seeps located within the oxygen minimum zone off the Oregon and California margins the PIs have identified up to 17 co-occurring dorvilleid species, including 10 in a single genus. The PIs hypothesize that this annelid group, through exceptional tolerance to low oxygen and high sulfide concentrations, has found a suite of niches which it alone has been able to exploit, and as a result has experienced evolutionary release in the absence of predators and competitors. The PIs propose to use this dorvilleid assemblage as a model system with which to investigate how metazoan communities evolve in and adapt to extreme sulfide conditions. By mapping ecological features onto a phylogenetic framework, the PIs will identify correlations among ecology, physiology, life history and evolutionary history that help elucidate the mechanisms of speciation under extreme stress. The PIs anticipate that dorvilleid polychaetes will ultimately provide a superb metazoan model for integrated extremophile research. A partnership facilitated by California COSEE (Center for Ocean Science Education Excellence) will allow the PIs to pursue a rigorous education and outreach effort. Emerging findings will be incorporated as part of a current NSF-funded Sea Floor Science project (ISE #0229063) at the Ocean Institute.