Collaborative: The Predictive Nature of Microbial Biofilms for Cuing Larval Settlement at Deep-Sea Hydrothermal Vents

四十多年的研究表明，独特的热液喷口居民的微小的自由游泳的后代可以在它们专门的栖息地之间有效地分散。然而，我们对这些幼虫如何通过在合适的地点找到并定居来完成旅程几乎一无所知。这个问题仍然是深海生态中尚未解决的关键难题之一，随着热液喷口受到人类影响的威胁，这个问题的解决变得越来越重要。研究人员认为，首先在喷口形成的细菌薄膜是幼虫定居的良好路标，因为它们表明热液喷口适合生命。该项目采用了现场实验、尖端分子生物学技术和热液喷口幼虫和培养细菌膜的船上实验相结合的方案。该项目还将一个以本科为主的机构(西华盛顿大学)的本科生研究实习生与两个研究机构(罗格斯大学和伍兹霍尔海洋研究所)的本科生研究实习生联系起来，同时在海上共同开展该项目。最后，该团队正在制作一部科学行动纪录片，里面充满了海洋科学和探索，打算用于电视发行和博物馆放映。研究人员正在利用深海喷口、船上和潜水作业的镜头以及实验室工作来制作一部纪录片，突出科学研究的基础--假说驱动的研究、科学方法的应用以及批判性思维的重要性--所有这些都是在一个令人兴奋但受到威胁的生态系统的研究框架内。热液喷口是特别容易处理的系统，用于研究生物膜在幼虫定居中的作用，因为喷口的生物膜相对较低；喷口动物严格依赖喷口微生物，通常是通过定居后获得的共生伙伴关系；以及在常见的幼虫池范围内存在环境变化。此外，数十年来对模式生物中定居的研究使我们对生物膜线索有了很好的洞察；对喷口的定居模式有了坚实的基础了解；我们现在有了收集、识别和培养喷口幼虫和微生物的优秀工具；现代环境“组学”技术是表征生物膜产生的生物线索的良好工具。该项目通过微生物生态学家和幼虫生态学家的密切合作，对微生物生物膜在构造热液喷口幼虫定居中的作用提供了前所未有的定量观察。短期定居试验、微生物“组学”工作和随后的船上定居试验相结合的现场计划允许调查小组利用实地试验对最能预测幼虫在野外定居的因素进行统计建模，然后用船上试验来检验这些预测，这些试验将协变条件解耦。这种对假定幼虫定居线索的广泛表征及其与在不同喷口栖息地生态位中殖民成功的关系，将有助于更广泛地了解在不同海洋生态系统中的殖民成功。了解幼虫的初始定居在热液喷口生态系统的恢复和恢复中所起的作用，对于制定深海采矿的知情管理计划至关重要。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Over four decades of research have shown that tiny free-swimming offspring of the unique inhabitants of hydrothermal vents can disperse effectively between their specialized habitats. Yet, we know almost nothing about how these larval animals complete the journey by locating and settling down in suitable locations. This question remains one of the key unresolved puzzles in the ecology of the deep sea and is becoming increasingly important to solve as hydrothermal vents are becoming threatened by human impacts. The investigators suggest that the films of bacteria that first form at vents are good signposts for settlement of larvae because they indicate that the hydrothermal vents are suitable for life. This project uses a combined program of field experiments, cutting-edge molecular biology techniques, and shipboard experiments with hydrothermal-vent larvae and cultured bacterial films. The project also connects undergraduate research interns at a primarily undergraduate institution (Western Washington University) with undergraduate research interns at two research institutions (Rutgers and Woods Hole Oceanographic Institution) while working on the project at sea together. Finally, the team is producing a science-in-action documentary filled with ocean science and exploration intended for television distribution and museum screenings. The investigators are using footage of the deep-sea vents, shipboard and diving operations, and laboratory work to create a documentary that highlights the foundation of scientific research—hypothesis-driven research, the application of the scientific method, and the importance of critical thinking—all in the framework of the study of an exciting, but threatened, ecosystem.Hydrothermal vents are particularly tractable systems in which to study questions about the roles of biofilms in larval settlement because biofilms at vents are relatively low-complexity; vent animals are strictly dependent on vent microbes, often through symbiotic partnerships acquired after settlement; and environmental variations are present within the range of a common larval pool. Moreover, decades of research on settlement in model organisms give us good insight into biofilm cues; there is solid foundational understanding about colonization patterns at vents; we now have excellent tools to collect, identify, and culture vent larvae and microbes; and modern environmental "-omics" techniques are a good tool to characterize biological cues produced by biofilms. The project provides an unprecedented, quantitative look into the role of microbial biofilms in structuring larval settlement at hydrothermal vents, achieved only through the close collaboration of microbial and larval ecologists. The combined field program of short-term settlement experiments, microbial "-omics" work, and subsequent shipboard settlement experiments allows the investigative team to use field experiments to statistically model the factors that best predict larval settlement in the field, then test those predictions with shipboard experiments that decouple covarying conditions. This extensive characterization of putative larval settlement cues and their relationship to colonization success in heterogeneous vent habitat niches will contribute to a broader understanding of colonization success across diverse marine ecosystems. Understanding the role that the initial settlement of larvae plays in the recovery and resilience of hydrothermal-vent ecosystems is critical to developing informed management plans for deep-sea mining.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.