Ray-finned fish evolution during the breakup of Pangaea: the Halecomorphi

盘古大陆分裂过程中射线鳍鱼的进化：Halecomorphi

• 批准号: 457839430
• 负责人: Dr. Adriana López-Arbarello
• 金额: --
• 依托单位: Sektion Paläontologie und Geobiologie
• 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/457839430?language=en
• 关键词: Ray; finned; fish; evolution; during

The geographic and climatic changes produced by the breakup of Pangaea during the Mesozoic directly influenced the evolution of vertebrates. In particular, the faunas of ray-finned fishes changed dramatically. At the beginning of this Era, ray-finned fishes were phylogenetically diverse and well represented by all known actinopterygian major clades (Cladistia, Chondrostei, Ginglymodi, Halecomorphi, and Teleostei). Numerous lineages within these clades went extinct by the end of the Mesozoic and actinopterygians developed into the nearly monophyletic modern fish faunas, composed mostly by teleosts (~33.000 living species vs. 14 spp. cladistians, 29 spp. chondrosteans, 7 spp. ginglymodians, and only one halecomorph). After more than two centuries of research and despite the efforts of the relatively few specialists in contrast to other fields of palaeontology, we still know very little about the tempo and mode of Mesozoic actinopterygian evolution and not even the phylogenetic relationships between and within the major clades of Actinopterygii are well understood. According to a recent study, climate change had been the main driver of actinopterygian macroevolution at least since the Late Jurassic. However, this study does not include sufficient taxa representing the main groups of Mesozoic ray-finned fishes, most of which went extinct by the end of this Era. Was climate change a major driver of the extinction of those lineages? Which are the rates of speciation and extinction, trait evolution and diversification in those extinct lineages? These and many other questions remain to be answered. The so-called ‘phylogenetic comparative methods’ (PCMs) are powerful tools to explore these and other palaeobiological issues, but they require robust phylogenetic hypotheses. With the ultimate aim to study macroevolutionary processes in ray-finned fish evolution during the Mesozoic through the application of PCMs, a series of projects have been planned to provide solid phylogenetic grounds to allow the application of these methods. Amongst them, this proposal is dedicated to the Halecomorphi. With a single living species, the bowfin, several aspects make the Halecomorphi particularly interesting from the macro-evolutionary point of view. Halecomorph fishes were very abundant and diverse during the Mesozoic, in particular in the Jurassic of nowadays Europe, which was subjected to significant geographic changes during that time, including the development of rich marine platforms and temporary epicontinental seas. Jurassic halecomorphs are ecologically varied, including fast-swimming predators like tunas, demersal opportunistic feeders very similar to the living bowfin, and numerous small-sized species of more generalized trophic morphology. Numerous species are known, but their high-level taxonomy and phylogenetic relationships are controversial. Therefore, this project is aimed to solve the systematics of these fishes using rigorous phylogenetic methodology.

中生代盘古大陆的解体所引起的地理和气候变化直接影响了脊椎动物的进化。特别是鳍鱼的动物群发生了巨大的变化。在这个时代开始时，鳍鱼的遗传多样性和所有已知的放线翼主要分支（Cladistia，Chondrostei，Ginglymodi，Halecomorphi和Teleostei）的代表。这些分支中的许多谱系在中生代末灭绝，放线菌门发展成为几乎单系的现代鱼类动物群，主要由硬骨鱼组成（约33.000个活物种对14个物种）。枝形类29种（cladistians）。chondrosteans，7 spp. ginglymodians，只有一个halecomorph）。经过两个多世纪的研究，尽管与其他古生物学领域相比，相对较少的专家做出了努力，但我们仍然对中生代Actinoptergian进化的克里思和模式知之甚少，甚至Actinoptergian主要分支之间的系统发育关系也没有很好地了解。根据最近的一项研究，至少从晚侏罗纪开始，气候变化一直是辐鳍类大进化的主要驱动力。然而，这项研究并没有包括足够的代表中生代鳍鱼主要群体的分类群，其中大多数在这个时代结束时灭绝。气候变化是这些血统灭绝的主要原因吗？在那些灭绝的谱系中，物种形成和灭绝的速度，特征进化和多样化的速度是多少？这些问题和许多其他问题仍有待回答。所谓的“系统发育比较方法”（PCMs）是探索这些和其他古生物学问题的有力工具，但它们需要强大的系统发育假设。最终目的是通过PCMs的应用研究中生代鳍鱼进化的宏观进化过程，一系列的项目已经计划提供坚实的系统发育的理由，使这些方法的应用。其中，这项建议是专门为Halecomorphi。由于有一个单一的物种，弓鳍鱼，从宏观进化的角度来看，几个方面使Halecomorphi特别有趣。盐形鱼类在中生代非常丰富和多样，特别是在今天的欧洲侏罗纪，这是受到重大的地理变化，在那个时候，包括丰富的海洋平台和临时的陆表海的发展。侏罗纪盐形生物在生态学上是多样的，包括快速游泳的捕食者，如金枪鱼，与生活的弓鳍鱼非常相似的底层机会主义者，以及许多更广义的营养形态的小型物种。许多物种是已知的，但他们的高级分类和系统发育关系是有争议的。因此，本计画的目的是利用严格的系统发生学方法来解决这些鱼类的系统分类问题。