Linking global change and deep-sea macrobenthos diversity – bathyal Atelostomata as a model taxon.

深海是地球上最大的生态系统，由于其庞大的面积和难以进入，我们对全球深海生物群及其控制机制的了解仍然模糊不清。虽然人们逐渐了解了化能合成生态系统，但半深海至深海平原和超深海海沟仍普遍未被探索。由于陆上深海沉积物的地质记录稀少，缺乏任何一组更高级的深海后生动物的连续地质/古生物记录，我们对深海古生物地理学和大型底栖动物演化的认识更加初步。在ODP/DSDP/IODP岩心样品中，从下白垩纪至上中新世沉积物中提取深海大型底栖动物遗骸的调查得出了惊人的结果：今天在深海中常见的棘皮动物（海参纲、海蛇尾纲、海星纲、海百合纲）不存在，只有不规则棘皮动物（Holasteroida、Spatangoida：Atelostomata）的刺经常出现。由于棘在形态上变化很大，对棘形态空间、其随时间的变化和棘积累率的评估有可能绘制深海多样性和生物量随全球变化而变化的地图。特别是，全球变暖导致出口生产力下降，由于初级生产力下降，特别是在开放的海洋环境中，为什么热带太平洋东部作为一个模型区，以澄清两个假设。i）无口动物棘多样性与新生代温暖期呈负相关，支持生产力-多样性关系; ii）无口动物棘丰度是生物量和输出生产力的表达，在温暖期显示出较低的值。从快速变化的新生代世界的选定间隔与巨大的海面和底层水温的变化，并考虑（中新世中期冷却，中新世中期气候最佳，渐新世晚期变暖; Oi-2c冰川作用和后果，上渐新世; Oi-2b冰川作用和后果）的Atelostomate刺。刺特征（例如，轴形态、刺的排列和频率、孔的形状/数量、尖端形状等）包括在数据矩阵中并进行统计处理。脊椎多样性的变化被认为是表达不断变化的生物多样性，并减少多样性和生物量预计在变暖期间。主成分分析的脊柱组合从上述时间间隔的帮助识别特定时间间隔和多样性变化之间的形态空间差异。这给了渐进（进化？）或突然（灭绝和物种形成/移民？）深海Atleostomata之间的区系变化以及全球变化期间区系周转/变化与向深海出口生产力波动的关系。

The deep-sea is the Earth’s largest ecosystem, and due to its sheer size and inaccessibility, our knowledge on global deep-sea biota and its controlling mechanisms is still ambiguous. While chemosynthetic ecosystems are progressively understood, the bathyal to abyssal plains and the hadal deep-sea trenches remain widely unexplored. Due to the scarce geologic record of deep-sea sediments onshore and the lack of continuous geological/palaeontological records of any group of higher deep-sea Metazoa, our knowledge on deep-sea palaeobiogeography and macrofauna evolution is even more rudimentary. A survey to extract remains of deep-sea macrobenthos from Lower Cretaceous to Upper Miocene sediments deposited at deep bathyal palaeo-waterdepths below 2000 m in ODP/DSDP/IODP core samples yielded astonishing results: Echinodermata (holothurians, brittle stars, sea stars, crinoids), today common in the deep-sea, are absent, while only spines of irregular echinoids (Holasteroida, Spatangoida: Atelostomata) occur frequently. Because the spines are morphologically highly variable, the assessment of spine morphospace, its changes in time and the spine accumulation rate bears the potential to map diversity and biomass changes in the deep-sea in response to global change. In particular, global warming results in decreasing export productivity due to lower primary productivity especially in open oceanic settings, why the eastern tropical Pacific serves as a model area to clarify two hypotheses. i) Atelostomate spine diversity correlates inversely with Cenozoic warm periods, supporting the productivity-diversity relation and ii) atelostomate spine abundance is expression of biomass and export productivity, showing lower values in warm phases. Atelostomate spines from selected intervals of the rapidly changing Cenozoic world with massive sea surface and bottom water temperature changes and were considered (Mid-Miocene cooling, Mid-Miocene climatic optimum, late Oligocene warming; Oi-2c glaciation and aftermath, Upper Oligocene; Oi-2b glaciation and aftermath). Spine characters (e.g. shaft morphology, arrangement and frequency of thorns, shape/number of pores, shape of tips etc.) are included in a data matrix and statistically processed. Variations in spine diversity are considered to express changing biodiversity, and decreasing diversity and biomass is expected during warming periods. A principal component analyses of the spine assemblages from the intervals above aid the recognition of morphospace disparity between the time-specific intervals and diversity changes. This give additionally clues on gradual (evolution?) or abrupt (extinction and speciation/immigration?) faunal changes between the deep-sea Atleostomata and the relation of faunal turnovers/changes to fluctuating export productivity into the dee-sea during global change.