Genetic signature of Last Glacial Maximum regional refugia in a circum-Antarctic sea spider

Metadata record for data collected as part of Australian Antarctic Science project 3010 in the Australian Antarctic program.

From the abstract of the referenced paper:

The evolutionary history of Antarctic organisms is becoming increasingly important to understand and manage population trajectories under rapid environmental change. The Antarctic sea spider Nymphon australe, with an apparently large population size compared with other sea spider species, is an ideal target to look for molecular signatures of past climatic events. We analysed mitochondrial DNA of specimens collected from the Antarctic continent and two Antarctic islands (AI) to infer past population processes and understand current genetic structure. Demographic history analyses suggest populations survived in refugia during the Last Glacial Maximum. The high genetic diversity found in the Antarctic Peninsula and East Antarctic (EA) seems related to multiple demographic contraction-expansion events associated with deep-sea refugia, while the low genetic diversity in the Weddell Sea points to a more recent expansion from a shelf refugium. We suggest the genetic structure of N. australe from AI reflects recent colonization from the continent. At a local level, EA populations reveal generally low genetic differentiation, geographically and bathymetrically, suggesting limited restrictions to dispersal. Results highlight regional differences in demographic histories and how these relate to the variation in intensity of glaciation-deglaciation events around Antarctica, critical for the study of local evolutionary processes. These are valuable data for understanding the remarkable success of Antarctic pycnogonids, and how environmental changes have shaped the evolution and diversification of Southern Ocean benthic biodiversity.

本数据集元数据记录源自澳大利亚南极计划旗下第3010号南极科学项目所采集的科研数据。

据所引用论文的摘要内容：
近年来，在全球环境快速变化的背景下，解析南极生物的演化历史，对于理解并管控种群动态轨迹的重要性日益凸显。南极海蜘蛛*Nymphon australe*相较于其他海蜘蛛类群，种群规模看似更为庞大，是探寻古气候事件分子印记的理想研究对象。本研究对采自南极大陆及两座南极岛屿（Antarctic Islands，AI）的样本开展线粒体DNA（mitochondrial DNA）分析，以推演其过往种群动态过程，并解析当前的遗传结构。种群历史分析结果显示，该物种种群在末次盛冰期（Last Glacial Maximum）期间于避难生境中存活下来。在南极半岛与东南极（East Antarctic，EA）海域发现的高遗传多样性，似乎与深海避难生境相关的多次种群收缩-扩张事件存在关联；而威德尔海（Weddell Sea）的低遗传多样性，则表明其种群是近期从陆架避难生境扩张而来。我们认为，两座南极岛屿（AI）上的*Nymphon australe*种群遗传结构，反映了其从南极大陆近期拓殖的过程。在局域尺度下，东南极种群在地理与水深维度上均展现出较低的遗传分化，说明其扩散受到的限制较为有限。本研究结果揭示了南极周边冰川作用-冰消作用强度差异下的种群历史区域差异，这对于解析当地的演化过程具有关键意义。这些数据对于理解南极海蜘蛛类群的显著演化成功，以及环境变化如何塑造南大洋底栖生物多样性的演化与分化，均具有重要科研价值。