NSFGEO-NERC: Mechanisms of Adaptation to Terrestrial Antarctica through Comparative Physiology and Genomics of Antarctic and sub-Antarctic Insects

南极洲寒冷干燥的陆地环境不适合昆虫栖息，只有三种蚊子在南极洲安家。在这些物种中，南极Belgica是唯一专门在南极洲发现的物种，自从大约3000万年前南美洲大陆分裂以来，它一直是南极洲的居民。因此，这个物种是一个很好的系统，可以模拟南极洲反复发生的冰川事件和气候变化的生物史。这种昆虫也是极端适应的经典例子，之前的许多工作都集中在识别允许这种物种在其他昆虫无法生存的地方生存的遗传和生理机制。然而，由于缺乏来自密切相关的南极和亚南极物种的信息，很难准确地确定在南极洲生存所需的独特的进化适应。这个项目将比较四种从亚南极到南极栖息地的环境梯度的蚊子物种的适应能力、基因组序列和种群特征。除了南极洲以外，这些物种包括两个严格属于亚南极的物种和第三个原产于亚南极但入侵了南极洲部分地区的物种。研究人员由来自美国、英国、智利和法国的科学家组成，他们将对不同地理范围的昆虫进行采样，测量它们耐受环境压力(即寒冷和干燥)的能力，量化对压力的分子反应，并比较基因组的组成和遗传多样性的模式。这项研究将有助于更好地了解对极端的适应，了解地球上的生物多样性，了解和预测伴随环境变化的变化。该项目将培训两名研究生和两名博士后研究人员，一名K-12教育工作者将成为实地团队的成员，帮助进行实地考察，并促进与美国学校的联系。该项目包括与几个STEM教育组织的伙伴关系活动，向K-12和中学生提供教育内容。这是一个由国家科学基金会地球科学理事会(NSF/GEO)和英国国家环境研究理事会(NERC)通过NSF/GEO-NERC牵头机构协议共同资助的项目。该协定允许美国和英国提交一个单一的联合提案，并由该机构进行同行审查，该机构的调查员在预算中所占比例最大。每个机构为与其本国有关的预算和调查人员的比例提供资金。英国对该项目的参与包括将科学家部署为现场团队的一部分，在遥远的南极地点支持现场和采样后勤，以及基因组测序、注释和分析。这个项目的重点是关键的生理适应和分子过程，使少数昆虫物种得以在南极洲生存。集中的物种都没有翅膀，扩散能力有限，这表明在这些物种范围内，也有巨大的潜力在当地适应不同的环境条件。中心假设是，相似的分子机制既驱动种群水平对当地环境条件的适应，也推动生活在不同环境中的物种之间的宏观进化变化。该项目的具体目标是1)通过比较生理学和转录组学来表征保守的和物种特有的对极端环境的适应，2)比较这些物种的基因组序列以确定极端适应的遗传特征，以及3)调查每个物种的多样性和局部适应的模式？利用种群基因组学研究范围。该项目建立了一个由来自美国、英国、智利和法国的研究人员组成的国际合作，他们在南极节肢动物的生物学、基因组学和保护方面有着共同的兴趣和互补的专业知识。该项目的更广泛影响包括培训学生，并与生活艺术和科学中心合作，为K-12学生设计和实施教育内容。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。

The cold, dry terrestrial environments of Antarctica are inhospitable for insects, and only three midge species make Antarctica home. Of these, Belgica antarctica is the only species found exclusively in Antarctica, and it has been a resident of Antarctica since the continent split from South America ~30 million years ago. Thus, this species is an excellent system to model the biological history of Antarctica throughout its repeated glaciation events and shifts in climate. This insect is also a classic example of extreme adaptation, and much previous work has focused on identifying the genetic and physiological mechanisms that allow this species to survive where no other insect is capable. However, it has been difficult to pinpoint the unique evolutionary adaptations that are required to survive in Antarctica due to a lack of information from closely related Antarctic and sub-Antarctic species. This project will compare adaptations, genome sequences, and population characteristics of four midge species that span an environmental gradient from sub-Antarctic to Antarctic habitats. In addition to B. antarctica, these species include two species that are strictly sub-Antarctic and a third that is native to the sub-Antarctic but has invaded parts of Antarctica. The researchers, comprised of scientists from the US, UK, Chile, and France, will sample insects from across their geographic range and measure their ability to tolerate environmental stressors (i.e., cold and desiccation), quantify molecular responses to stress, and compare the makeup of the genome and patterns of genetic diversity. This research will contribute to a greater understanding of adaptation to extremes, to an understanding of biodiversity on the planet and to understanding and predicting changes accompanying environmental change. The project will train two graduate students and two postdoctoral researchers, and a K-12 educator will be a member of the field team and will assist with fieldwork and facilitate outreach with schools in the US. The project includes partnership activities with several STEM education organizations to deliver educational content to K-12 and secondary students. This is a project that is jointly funded by the National Science Foundation's Directorate of Geosciences (NSF/GEO) and the National Environment Research Council (NERC) of the United Kingdom (UK) via the NSF/GEO-NERC Lead Agency Agreement. This Agreement allows a single joint US/UK proposal to be submitted and peer-reviewed by the Agency whose investigator has the largest proportion of the budget. Each Agency funds the proportion of the budget and the investigators associated with its own country. UK participation in this project includes deploying scientists as part of the field team, supporting field and sampling logistics at remote Antarctic sites, and genome sequencing, annotation, and analyses. This project focuses on the key physiological adaptations and molecular processes that allow a select few insect species to survive in Antarctica. The focal species are all wingless with limited dispersal capacity, suggesting there is also significant potential to locally adapt to variable environmental conditions across the range of these species. The central hypothesis is that similar molecular mechanisms drive both population-level adaptation to local environmental conditions and macroevolutionary changes across species living in different environments. The specific aims of the project are to 1) Characterize conserved and species-specific adaptations to extreme environments through comparative physiology and transcriptomics, 2) Compare the genome sequences of these species to identify genetic signatures of extreme adaption, and 3) Investigate patterns of diversification and local adaptation across each species? range using population genomics. The project establishes an international collaboration of researchers from the US, UK, Chile, and France with shared interests and complementary expertise in the biology, genomics, and conservation of Antarctic arthropods. The Broader Impacts of the project include training students and partnering with the Living Arts and Science Center to design and implement educational content for K-12 students.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.