Collaborative Research: Functional evolution of the mammalian backbone: insights from the forerunners of mammals

修订标题：合作研究：哺乳动物脊椎的功能进化：来自哺乳动物祖先的见解哺乳动物以其广泛的运动行为而闻名，包括独特的步态，如飞奔和跳跃。这些步态是通过将脊柱分成两个不同的区域而实现的：胸部区域，它承载肋骨并帮助呼吸;腰部区域，它没有肋骨，高度移动的并具有运动功能。结合起来，这两部分的脊椎允许哺乳动物呼吸和移动同时进行，允许长时间使用高速步态。但是，这种关键的哺乳动物特征是如何进化的呢？利用尖端的3D技术，沿着丰富的哺乳动物及其祖先的化石记录，这项研究将追溯哺乳动物脊椎的起源和进化，以及它与哺乳动物特有的运动行为发展的联系。这项工作将加深我们对哺乳动物的一个关键特征的历史的理解，以及具有重要医学意义的骨骼部分。将通过两个主要渠道传播研究成果。首先，获奖的YouTube频道“The Brain Scoop”将制作一系列在线教育视频。该系列将包括三集，以有趣和引人入胜的方式记录研究项目的不同阶段，其核心目的是鼓励青少年和年轻人对科学，技术，工程和数学（STEM）主题的兴趣增加。第二，“大脑勺”系列将被用作菲尔德博物馆N。W.哈里斯学习收藏。该盒子将提供给K-12教育工作者借用和在他们的教室使用，并将包括复制标本和与每一集相关的活动，这些活动与下一代科学标准直接相关。技术摘要哺乳动物以其广泛的运动行为而闻名，包括独特的不对称步态，如飞奔和跳跃。不对称的步态是通过将背脊柱（胸带和骨盆带之间的区域）细分为两个形态和功能不同的区域而实现的。在前面，胸部区域承载肋骨并且专门用于呼吸，而在后面，背腹移动的腰部区域在运动中起作用。结合起来，区域化的背椎骨允许哺乳动物同时呼吸和移动，允许长时间使用高速步态。但是，这种关键的哺乳动物特征是如何进化的呢？现代物种几乎没有提供任何信息来研究这个基本的进化问题，因为它们都拥有不同的胸部和腰部区域。然而，哺乳动物所属的Synapsida分支有丰富的化石记录，为哺乳动物的起源和进化提供了详细的视图。利用尖端的形态测量，生物力学和3D数字建模技术，该项目采取了深时间的方法来检查化石突触中脊柱的功能，并追踪胸腰椎区域和背腹移动性的起源和演变。将采用四种协同方法：1）形态测量数据将用于检查现代四足动物和化石联会动物背侧脊柱的形态功能区域化程度; 2）将对包括联会动物-哺乳动物过渡的现代四足动物脊柱进行离体弯曲实验，以确定形式和功能之间的联系; 3）将在化石突触脊柱的3D数字模型上进行新的虚拟弯曲实验，以确定它们的运动倾向; 4）将在严格的系统发育背景下合成数据，以重建胸腰椎区域和背腹移动性的起源和进化。

Revised Title: Collaborative Research: Functional evolution of the mammalian backbone: insights from the forerunners of mammalsNon-technical AbstractMammals are known for their great range of locomotor behaviors, including unique gaits such as galloping and bounding. These gaits are made possible by the subdivision of the backbone into two distinct regions: the thoracic region, which bears ribs and aids in breathing; and the lumbar region, which is ribless, highly mobile and functions in locomotion. Combined, these two sections of the backbone allow mammals to breathe and move simultaneously, permitting the use of high speed gaits for prolonged periods of time. But, how did this key mammalian trait evolve? Using cutting-edge 3D technology, along with the rich fossil record of mammals and their ancestors, this research will trace the origin and evolution of the mammalian backbone and its link with the development of mammal-specific locomotor behaviors. The work will deepen our understanding of the history of a key characteristic of mammals and part of the skeleton that is of great medical importance. Dissemination of the research will occur via two primary outlets. First, a series of educational online videos will be produced by the award-winning YouTube channel "The Brain Scoop". The series will include three episodes documenting different stages of the research project in a fun and engaging way, with the core aim to encourage an increased interest in Science, Technology, Engineering and Mathematics (STEM) topics among teenagers and young adults. Second, the "The Brain Scoop" series will be used as the foundation for an 'Experience Box' in the Field Museum's N. W. Harris Learning Collection. The box will be available for K-12 educators to borrow and use in their classrooms, and will include replica specimens and activities related to each episode that are directly tied to Next Generation Science Standards.Technical AbstractMammals are known for their great range of locomotor behaviors, including unique asymmetric gaits such as galloping and bounding. Asymmetric gaits are made possible by the subdivision of the dorsal vertebral column (the area between the pectoral and pelvic girdles) into two morphologically and functionally distinct regions. Anteriorly, the thoracic region bears ribs and is specialized for respiration, whereas posteriorly the dorsoventrally mobile lumbar region functions in locomotion. Combined, the regionalized dorsal vertebrae allow mammals to breathe and move simultaneously, permitting the use of high speed gaits for prolonged periods of time. But, how did this key mammalian trait evolve? Modern species provide little information for examining this fundamental evolutionary question, as they all possess distinct thoracic and lumbar regions. However, the clade to which mammals belong, Synapsida, has a rich fossil record that provides a detailed view of the origin and evolution of mammals. Using cutting-edge morphometric, biomechanical, and 3D digital modeling techniques, this project takes a deep-time approach to examine function of the vertebral column in fossil synapsids, and to trace the origin and evolution of the thoracolumbar region and dorsoventral mobility. Four synergistic approaches will be utilized: 1) morphometric data will be used to examine the degree of morphofunctional regionalization of the dorsal vertebral column in modern tetrapods and fossil synapsids; 2) ex vivo bending experiments will be conducted on the vertebral columns of modern tetrapods bracketing the synapsid-mammal transition to determine the link between form and function; 3) novel virtual bending experiments will be carried out on 3D digital models of fossil synapsid vertebral columns to determine their propensity for movement; and 4) the data will be synthesized within a strict phylogenetic context to reconstruct the origin and evolution of the thoracolumbar region and dorsoventral mobility.