Diversität und Evolution Antarktischer Gastropoden: ein genomischer Ansatz

南极腹足动物的多样性和进化：基因组方法

• 批准号: 238768991
• 负责人: Professor Dr. Michael Schrödl
• 金额: --
• 依托单位: School of Biological Sciences
• 依托单位国家: 德国
• 项目类别: Infrastructure Priority Programmes
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/238768991?language=en
• 关键词: Diversit; und; Evolution; Antarktischer; Gastropoden

The Antarctic irwertebrate fauna appears highiy diverse, but is only localiy and sporadically explored - and already threatened by global climate change. Gastropods are abundant, species rieh, ecologically and economically irnportant, count with a rieh fossil record and are wellestablished äs model organisms for many scientific disciplines. Most of the roughly 600 Antarctic gastropod species are regarded valid at the mornent based on shell features of often just a few or single specimens. Intraspecific morphological variability, soft pari anatomy, biology» and ecology are usually unknown, and many synonyms have been proposed. Wolecular data are limited to CÖI barcode sequences of few individuals of the more common species: Phylogenetic analyses of single genes suggest complexes of cryptic species or deep lineages, which may show distinct geographic distributions and special ecological niches. Rarity of species or samples prohibits general population genetics approaches. The prirnary goal of our herein proposed project is revealing the species diversity of Antarctic gastropods comprehensively and reliably. In addition to mltochondrial CÖI, we will use next generation sequencing (NGS) and newly established methods (double digest Restriction Associated DMA sequencing, ddRADseq) to efficiently generate a multitude of independent nuclear genomic sequence markers. We will include all species and subsamples from rnore than 2000 Southern Öcean gastropod samples available at the ZSM Mollusca collection suitable for genetic studies, plus further material to be collected at expeditions or from other museums. We will perform phylogenetic analyses (ML, Bayes, in subgroups BEST) and combined, up~to-date molecular species delimitation approaches {ABGD, GMYCS BP&P), An integrative taxonomic approach reiying on congruence will be applied to revea! conservative and reliable evolutionary species units, which will be used for diversity analyses, We will also explore genomic evolutionary archives of seiected gastropod lineages performing fossil-calibrated BEAST chronograms. The dynamics of diversification will be analyzed via recent Birth-Death-Shift models, and historical biogeography will be reconstructed using recent Software (e.g, RASP). With our massif genomic data from many subtaxa we will test current paradigms on biogeography and evolution, such äs glacial cycles causing an "Antarctic speciation pump", and evaluate competing hypotheses on glacial refuges and migration scenarios. The herein proposed combination of ddRADseqs with up~to~date multi-iocus analyses is novel, extremely cost and time effective, and can include thousands instead of few specimens» without any a priori selectron. It is expected to be very powerful to delimitate newty collected, unrecognized, or cryptic species, even jf badly sampled or just represented by singletons. We trust this approach is a quantum leap forward referring to the exploration of remote and highiy diverse faunas, Our pioneer project thus will generate massif novel and comprehensive data and results on Antarctic gastropods which might change previous ideas on e.g. biogeography or ecology, that aimost entirely relted on ill-defined „morphospecies" concepts, Eventually, evolutionary species units will be characterized morphologically, geographicaliy and ecologically. This will be the basis for future studies on past evolutionary adaptations, ecological niche rnodelling, and predicting response to global change and ocean acidification.

南极的Irwertebrate动物区系似乎是高度多样的，但仅是局部探索的，并且已经受到全球气候变化的威胁。腹足植物丰富，物种Rieh，生态和经济上至关重要，具有RIEH化石记录，并且是许多科学学科的良好模型生物。大约600种南极腹足动物中的大多数在早晨被认为是有效的，因为通常只有几种或单个物种的壳特征。通常未知，种内形态学变异性，软培训，生物学»和生态学，并且已经提出了许多同义词。多多数数据仅限于少数更常见物种的个体的Cöi条形码序列：单基因的系统发育分析表明，加密物种或深层谱系的复合物，这可能显示出不同的地理分布和特殊的生态壁ches。我们提出的项目的主要目标的稀有性是全面，可靠地揭示了南极腹足动物的物种多样性。除了mltooncondrialCöi外，我们还将使用下一代测序（NGS）和新建立的方法（双消化限制相关的DMA测序，ddradseq）来有效地生成众多独立的核基因组序列标记。我们将进行系统发育分析（ML，贝叶斯，在亚组中最好），并结合使用，〜到期的分子划界方法（ABGD，GMYCS BP＆P），这是一种综合性的综合性分类方法，将适用于revea！保守和可靠的进化物种单位将用于多样性分析，我们还将探索执行化石校准的野兽时间表的可见腹足动物谱系的基因组进化档案。多元化的动力将通过最近的出生转移模型分析，历史生物地理将使用最近的软件（例如RASP）重建。借助来自许多亚tapa子的地层基因组数据，我们将测试当前关于生物地理和进化的范例，例如冰川周期引起“南极规格泵”，并评估冰川雷谱和迁移情景的竞争假设。本文提出的DDRADSEQS与〜date多iocus分析的ddradseqs组合是新颖的，非常成本和时间效率，并且可以包含数千个而不是少数物种»而无需任何先验的选择。预计将非常有力，可以划定收集，未识别或加密物种，甚至jf糟糕的采样或刚刚由单胎代表。我们相信这种方法是指探索远程和高级潜水员动物区系的量子飞跃，因此我们的先驱项目将产生弥撒小说和全面的数据，并对南极腹足类动物产生结果，这可能会改变以前的想法。生物地理学或生态学，最全部降低了定义不明的“形态学”概念，最终，进化物种单位将被描述，地理和生态学上。这将是对过去进化适应，生态生态元素的未来研究的基础，并预测了对全球变化和海洋酸化的反应。