Collaborative Research: Dinosaur Jaw Muscle Evolution and the Origins of Avian Cranial Kinesis

仅次于羽毛和飞行，头盖骨之间的运动(颅骨运动)是鸟类最明显的进化适应，也是世界各地课堂上使用的肌肉骨骼生物力学的教科书范例。然而，这项创新的起源仍然停留在恐龙-鸟类化石记录中。该奖项支持的研究人员将使用化石和活恐龙的3D解剖和计算建模来探索鸟类头部的生物力学进化。该项目将建立古生物学家、比较生物机械学家和工程师之间的跨学科合作。3D模型、发现和其他数据将用于培训密苏里州中部的K-12学生和教师，以及比较生物力学和鸟类进化方面的年轻研究人员。该项目综合了解剖学、生物力学、古生物学、工程学和计算机科学，并将通过REU支持和暑期实习培养博士后研究员、研究生和本科生。密苏里州中部和阿巴拉契亚地区的教师将通过身临其境的实验室实习和研讨会，通过密苏里大学的Inside恐龙体验和俄亥俄大学的可见互动恐龙(VID)，接受与鸟类解剖学、生物力学和进化相关的STEM主题的培训。公众将通过密苏里州的恐龙和洞穴人科学博览会和VID途径进行宣传。头骨和肌肉的3D模型将作为互动网络模块提供给教育和研究。始祖龙之间的头骨运动是脊椎动物进化中一项关键创新的经典例子，导致了增强的头骨灵活性，极端的饮食灵活性，以及随后的冠枝鸟类的适应性辐射。在从恐龙到鸟类的进化过程中，下颌肌肉移动了位置，失去了骨骼连接，颅内关节变得越来越灵活。该奖项支持的研究将使用新的3D计算方法分析非鸟类和鸟类恐龙头盖骨内颌肌力的演变。这些发现将有助于估计灭绝类群摄食过程中的颅内关节负荷，并探索个别颌肌在颅骨功能上的进化。研究结果将与神经解剖学数据相结合，以揭示大脑和喂食装置之间的共同进化关系。恐龙喂食器的新3D模型将为未来许多其他脊椎动物的颅骨功能形态研究提供模板。这项工作将为脊椎动物摄食的多体动力学模型提供补充和必要的基础，将为材料特性测试和XROMM分析以及颅骨组织的软骨建模提供指导，并将开发可用于测试颅骨模块化和颅骨功能模式的3D数据集。研究结果将在科学会议上公布，并发表在同行评议的期刊上。

Next to feathers and flight, movements between bones of the skull (cranial kinesis) is the most recognizable evolutionary adaptation of birds and a textbook example of musculoskeletal biomechanics used in classrooms worldwide. However, the origins of this innovation remain trapped within the dinosaur-bird fossil record. The researchers supported by this award will explore the biomechanical evolution of the avian head using 3D anatomical and computational modeling of fossil and living dinosaurs. This project will create interdisciplinary collaborations of paleontologists, comparative biomechanists and engineers. 3D models, discoveries and other data will be used to train K-12 students and teachers in mid-Missouri as well as young investigators in comparative biomechanics and avian evolution. This project integrates anatomy, biomechanics, paleobiology, engineering, and computer science and will train a postdoctoral researcher, graduate, and undergraduate students through REU support and summer internships. Mid-Missourian and Appalachian teachers will be trained in STEM topics related to avian anatomy, biomechanics and evolution through immersive, embedded lab internships and workshops through the Inside Dinosaurs experience at University of Missouri and the Visible Interactive Dinosaur (VID) at Ohio University. Public outreach will occur through Missouri's Dinosaurs & Cavemen science exposition and VID avenues. 3D models of skulls and muscles will be made available as interactive web modules for education and research. Cranial kinesis among archosaurs is a classic example of a key innovation in vertebrate evolution, resulting in enhanced cranial dexterity, extreme dietary flexibility, and the subsequent adaptive radiations of crown-clade birds. During the evolutionary transition from dinosaurs to birds, jaw muscles shifted positions, bony connections were lost, and intracranial joints became increasingly flexible. Studies supported by this award will analyze the evolution of jaw muscle forces within the cranium of non-avian and avian dinosaurs using novel 3D computational methods. These findings will allow the estimation of intracranial joint loading during feeding in extinct taxa and explore the evolution of individual jaw muscles in cranial function. The results will be integrated with neuroanatomical data to uncover the coevolutionary relationships between the brain and feeding apparatus. New 3D models of the dinosaur feeding apparatus will provide the template for numerous future studies of cranial functional morphology in other vertebrates. This work will complement and provide the necessary foundation for multi-body dynamic models of vertebrate feeding, will provide guidance for material properties testing and XROMM analysis, chondral modeling of cranial skeletal tissues, and will develop 3D datasets that can be used to test patterns of cranial modularity and skull function. Results from the studies will be presented at scientific meetings and published in peer-reviewed journals.