Reconstructing the lost cartilaginous epiphyses in extinct archosaurs' limbs

重建已灭绝的主龙四肢中丢失的软骨骨骺

• 批准号: EP/Y029356/1
• 负责人: John Hutchinson
• 金额: $ 23.84万
• 依托单位: Royal Veterinary College
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FY029356%2F1
• 关键词: Reconstructing; lost; cartilaginous; epiphyses; extinct

Locomotion is among the most important function involved in tetrapod evolutionary success. Understanding how locomotion in current species evolved implies to study their fossil record. Evolutionary biomechanics tackles this topic, by estimating locomotor abilities of extinct organisms by observing their extant relatives. Particular efforts have been made to infer the locomotion in non- avian dinosaurs and other extinct archosaurs. However, as in most other tetrapods, archosaur limb bones have cartilaginous epiphyses that do not fossilise. This leads to high levels of uncertainty when conducting biomechanical analyses on such animals. Surprisingly, corrective strategies remained rather subjective and simplistic, failing to propose a robust way to account for missing cartilage. Here I propose to answer to this critical issue by concretely REconstructing the LOst CArTilaginous Epiphyses of extinct archosaurs, using cutting-edge quantitative methods. Focusing on the femur, the three-dimensional characteristics of a large sample of archosaurs will be used to estimate the missing epiphyses of fossil species. Subsequently to the study of modern morphological diversity, I will develop the protocol by assessing its accuracy to reconstruct epiphyses in a controlled virtual experimentation on extant species. I will also stress robustness to sampling variability to give the degree of confidence to put on the reconstruction. Finally, the impact of reconstructions will be tested by conducting a comparative biomechanical analysis. At the crossroads of quantitative vertebrate palaeontology, evolutionary biology and biomechanics, the project ambitions to develop the most objective and reliable way to date to reconstruct the lost epiphyses in extinct archosaurs. The unprecedented outcomes of the project should deeply impact inferences about how extinct archosaurs could locomote, and will open perspectives to generalise the approach to any other tetrapod group.

运动是四足动物进化成功的最重要的功能之一。了解当前物种的运动是如何进化的，意味着要研究它们的化石记录。进化生物力学通过观察现存生物的近亲来估计灭绝有机体的运动能力，从而解决了这个问题。已经做出了特别的努力来推断非鸟类恐龙和其他已灭绝的始祖龙的运动。然而，就像在大多数其他四足动物中一样，始祖龙的四肢骨骼具有不会化石的软骨骨痂。这导致在对这类动物进行生物力学分析时存在很高的不确定性。令人惊讶的是，矫正策略仍然相当主观和简单化，未能提出一种可靠的方法来解释软骨缺失。在这里，我建议通过使用尖端的定量方法，具体重建灭绝的始祖龙丢失的软骨骨面来回答这个关键问题。以股骨为重点，将利用大样本始祖龙的三维特征来估计化石物种缺失的骨痂。在研究了现代形态多样性之后，我将通过评估其准确性来开发该方案，以在对现有物种的受控虚拟实验中重建骨痂。我还将强调采样变异性的稳健性，以给出重建的置信度。最后，通过进行比较生物力学分析来测试重建的影响。在定量脊椎动物古生物学、进化生物学和生物力学的十字路口，该项目雄心勃勃地开发出到目前为止最客观和可靠的方法来重建灭绝的原始龙丢失的骨痂。该项目史无前例的结果应该会深刻影响关于灭绝的始祖龙如何移动的推断，并将开辟新的视角，将这种方法推广到任何其他四足类。