NSFGEO-NERC: Southern Ocean diatoms and climate change: quantifying the relative roles of diversity and plasticity in evolution

众所周知，气候变化正在迅速改变极地栖息地。然而，这些栖息地中的生物将如何进化和适应气候变化在很大程度上是未知的。这阻碍了预测海洋生态系统未来变化的努力。这项研究将研究硅藻是如何适应环境变化的，硅藻是南大洋中一种重要的浮游生物。在前往南大洋的研究巡航中，将从南大洋的不同区域取样硅藻，包括德雷克海峡、南大洋的太平洋部分和罗斯海。将对样本进行处理，以检查该领域的遗传多样性。在实验室里，将进行进化实验，以测量对温度升高和海洋酸化的适应速度。野外种群多样性的数据与适应率的数据相结合，将为海洋硅藻的“可进化性”提供关键的见解。本项目将资助博士生1名、博士后1名、本科生数名。这些科学家将学习实验进化的基础知识，这是海洋气候变化生物学领域急需的一套技能。该项目还包括与梅特卡夫海洋与环境报告研究所的合作。梅特卡夫研究所将设计和实施一个会议，重点讨论与进化和气候变化有关的当前研究，该会议将在美国国家科学作家协会（NASW）的年会上举行。虽然气候变化正在迅速改变极地栖息地，这一点大家都很清楚，但适应寒冷的、具有重要生物地球化学意义的浮游植物的进化反应基本上是未知的，这是一个重大的知识空白，阻碍了预测海洋食物网底部未来变化的努力。生理和遗传变异是理解浮游植物进化过程的关键参数，但对南大洋硅藻来说，它们基本上是未知的。这两个因素在野外种群中的程度（生理和遗传变异）以及它们之间的相互作用将影响适应冷的硅藻如何以及是否能够对变化的环境作出反应。该项目以硅藻为重点，包括a)通过德雷克海峡、南大洋太平洋部分和罗斯海进行实地工作，以确定硅藻的遗传多样性；B)实验室实验，评估当代硅藻种群的生理变异范围；c)实验室进化实验，评估遗传多样性和生理变异的结合如何影响环境变化下硅藻的进化潜力。这项研究将揭示生理变异、遗传多样性和进化潜力之间的一般关系，这些关系可能适用于微生物分类群和地理区域，从而大大改善全球变化下海洋生态系统变化的预测工作。该研究的结果可以整合到开发模型中，这些模型将进化纳入预测未来气候变化情景下的生态系统变化。本项目将资助博士生1名、博士后1名、本科生数名。这些科学家将学习实验进化的基础知识，这是海洋气候变化生物学领域急需的一套技能。该项目还包括与梅特卡夫海洋与环境报告研究所的合作。梅特卡夫研究所将设计和实施一个会议，重点讨论与进化和气候变化有关的当前研究，该会议将在美国国家科学作家协会（NASW）的年会上举行。

It is well known that climate change is rapidly altering polar habitats. However, it is largely unknown how organisms in those habitats will evolve and adapt in response to climate change. This hampers efforts to predict future changes in marine ecosystems. This research will examine how diatoms, an important group of plankton in the Southern Ocean, adapt to environmental change. During a research cruise to the Southern Ocean, diatoms will be sampled from different regions of the Southern Ocean, including the Drake Passage, the Pacific Sector of the Southern Ocean and the Ross Sea. Samples will be processed to examine genetic diversity in the field. In the lab, evolution experiments will be conducted to measure the rates of adaptation to increasing temperature and ocean acidification. Data on the diversity of field populations combined with data on rates of adaptability will provide key insights into the "evolvability" of marine diatoms. This project will support a doctoral student and a postdoctoral researcher as well as several undergraduates. These scientists will learn the fundamentals of experimental evolution, a skill set that is sorely needed in the field of ocean climate change biology. The project also includes a collaboration with the Metcalf Institute for Marine and Environmental Reporting. The Metcalf Institute will design and implement a session focused on current research related to evolution and climate change to be held at the annual conference of the National Association of Science Writers (NASW). Although it is well understood that climate change is rapidly altering polar habitats, the evolutionary response of cold-adapted, biogeochemically important phytoplankton is essentially unknown and represents a major knowledge gap that hampers efforts to predict future changes at the base of the marine food web. Both physiological and genetic variation are key parameters for understanding evolutionary processes in phytoplankton but they are essentially unknown for Southern Ocean diatoms. The extent of these two factors in field populations (physiological and genetic variation) and the interaction between them will influence how and whether cold-adapted diatoms can respond to changing environments. This project is focused on diatoms and includes a combination of a) field work to identify genetic diversity within diatoms across the Drake Passage, the Pacific sector of the Southern Ocean and the Ross Sea, b) experiments in the lab to assess the range of physiological variation in contemporary populations of diatoms and c) evolution experiments in the lab to assess how the combination of genetic diversity and physiological variation influence the evolutionary potential of diatoms under a changing environment. This research will uncover general relationships between physiological variation, genetic diversity, and evolutionary potential that may apply across microbial taxa and geographical regions, substantially improving efforts to predict shifts in marine ecosystems under global change. Results from this study can be integrated into developing models that incorporate evolution to predict ecosystem changes under future climate change scenarios. This project will support a doctoral student and a postdoctoral researcher as well as several undergraduates. These scientists will learn the fundamentals of experimental evolution, a skill set that is sorely needed in the field of ocean climate change biology. The project also includes a collaboration with the Metcalf Institute for Marine and Environmental Reporting. The Metcalf Institute will design and implement a session focused on current research related to evolution and climate change to be held at the annual conference of the National Association of Science Writers (NASW).