The Phylogenetic Relationships and Ecomorphological Diversification of Early Crocodylomorphs

早期鳄鱼的系统发育关系和生态形态多样化

• 批准号: 2705377
• 金额: --
• 依托单位: University College London
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2705377
• 关键词: Phylogenetic; Relationships; Ecomorphological; Diversification; Early

The diversity of organisms on Earth is unevenly distributed across time and the tree of life. An understanding of the dynamics and processes underpinning this observation is one of the central questions in the field of evolutionary biology. Crocodylomorphs, a group of pseudosuchian archosaurs that includes crocodilians and their extinct relatives, exhibit limited taxonomic and morphological diversity in the present day; however, extant forms represent only a fraction of the diversity achieved by the group throughout their around 230-million-year history. Crocodylomorphs have occupied a variety of ecologies, evolved a disparate range of morphologies, and survived two mass extinction events. This makes them an excellent system through which to study macroevolutionary processes; however, a well-resolved phylogeny is necessary to be able to effectively do so. Within Crocodylomorpha, the evolutionary relationships of 'early crocodylomorphs' ("Shenosuchia" + Protosuchia) are poorly known, as is the position of the thalattosuchians. As such, this project will seek to address this issue through the construction and analysis of a new phylogenetic dataset, including the development of an illustrated character list. This project will incorporate data from first-hand observation of a wide range of taxa and utilise CT scanning technology to study and characterize the internal anatomy of specimens. The resultant phylogeny will be applied, conducting cranial and post-cranial disparity analyses to better understand the group's ecomorphological radiation across the Triassic/Jurassic boundary. Doing so will allow for extinction selectivity and resilience to mass extinction events to be determined, with potential implications for present-day conservation efforts.

地球上生物的多样性在时间和生命之树上分布不均匀。了解支持这一观察的动力学和过程是进化生物学领域的核心问题之一。鳄形目是一组拟鳄类祖龙，包括鳄鱼及其已灭绝的近亲，在当今表现出有限的分类和形态多样性。然而，现存的形式仅代表该群体在其大约 2.3 亿年的历史中所实现的多样性的一小部分。鳄形类动物占据了多种生态系统，进化出不同的形态，并在两次大规模灭绝事件中幸存下来。这使得它们成为研究宏观进化过程的优秀系统。然而，要有效地做到这一点，必须有一个解决良好的系统发育史。在鳄形目中，“早期鳄形目”（“神鳄亚目”+原鳄亚目）的进化关系鲜为人知，海鳄亚目的地位也是如此。因此，该项目将寻求通过构建和分析新的系统发育数据集（包括开发插图字符列表）来解决这个问题。该项目将整合对多种类群的第一手观察数据，并利用 CT 扫描技术来研究和表征标本的内部解剖结构。由此产生的系统发育将被应用，进行颅内和颅后差异分析，以更好地了解该群体跨越三叠纪/侏罗纪边界的生态形态辐射。这样做将能够确定灭绝的选择性和对大规模灭绝事件的恢复力，对当今的保护工作具有潜在的影响。