Carapace growth in modern and fossil Spinicaudata (Crustacea: Branchiopoda): testing its applicability in unravelling Middle Jurassic to Late Cretaceous lacustrine faunal turnover in NE China

现代和化石棘尾动物（甲壳纲：鳃足纲）的甲壳生长：测试其在揭示中国东北部中侏罗世至晚白垩世湖泊动物群更替方面的适用性

• 批准号: 450530525
• 负责人: Dr. Manja Hethke
• 金额: --
• 依托单位: LWL-Museum für Naturkunde
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/450530525?language=en
• 关键词: Carapace; growth; modern; fossil; Spinicaudata

Spinicaudatan crustaceans became important elements of lake communities during Devonian times. They remained highly abundant for more than 300 million years, dominating the lacustrine invertebrate community. The Early Cretaceous global diversity peak was succeeded by a proposed dramatic decline during the Late Cretaceous and their exclusion from lake environments during the early Cenozoic. That decline of spinicaudatan presence in the fossil record forms an important aspect of general lake ecosystem evolution. Today, Spinicaudata represent an ecologically specialized clade adapted to temporary, fresh- to oligohaline wetlands that commonly do not support animals of higher trophic levels. The project aims at unravelling factors that controlled lacustrine faunal turnover in Middle Jurassic–Late Cretaceous fossillagerstätten of NE China by calculating the rate of change in macrobenthic community composition along environmental gradients of oxygen, temperature and nutrient availability. Biogeochemical proxy data (delta15N, delta13Corg, Corg/N, GDGT biomarkers) will be compiled for each fossiliferous bedding plane of four targeted formations for further statistical testing. Numerous bedding planes contain monospecific assemblages of Spinicaudata, rendering carapace morphology an additional important source of information for lake ecosystem change. Patterns of fossil morphological change along environmental gradients will be compared with results of proposed rearing experiments that target effects of oxygen, nutrient availability and temperature on carapace growth in modern species.

在泥盆纪，棘尾类甲壳动物成为湖泊群落的重要组成部分。它们在超过3亿年的时间里保持着高度丰富的数量，在湖泊无脊椎动物群落中占据主导地位。早白垩世全球多样性高峰之后，晚白垩世出现了急剧下降，并在新生代早期被排除在湖泊环境之外。化石记录中棘尾类的减少是湖泊生态系统演化的一个重要方面。今天，Spinicaudata代表了一个生态专业化的分支，适应临时的，新鲜的寡盐湿地，通常不支持更高的营养水平的动物。该项目旨在通过计算大型底栖动物群落组成沿着氧、温度和营养盐有效性等环境梯度的变化率，揭示控制中国东北中侏罗世-晚白垩世湖泊动物群更替的因素。将为四个目标地层的每个含油气层理面编制生物地球化学代用数据（delta 15 N、delta 13 Corg、Corg/N、GDGT生物标志物），以进行进一步的统计检验。许多层面包含单种组合的Spinicaudata，使甲壳形态湖泊生态系统变化的一个额外的重要信息来源。化石形态变化的模式，沿着环境梯度将进行比较，提出饲养实验，目标的影响，氧气，养分供应和温度对甲壳生长在现代物种的结果。