Brain evolution in archosaurs: new implications for scaling, function, and the evolution of the modern conditions in birds and crocodilians

古龙的大脑进化：对鸟类和鳄鱼的尺度、功能和现代条件进化的新影响

• 批准号: 0517257
• 负责人: Lawrence Witmer
• 金额: --
• 依托单位: Ohio University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-07-01 至 2011-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0517257&HistoricalAwards=false
• 关键词: Brain; evolution; archosaurs; new; implications

Brain evolution in archosaurs: new implications for scaling, function, and the evolution ofthe modern conditions in birds and crocodiliansLawrence M. WitmerOhio UniversityThe brain is justifiably regarded as the single most important organ, and thus its neurobiology and evolution have long been a central interest of organismal biology. This project studies brain evolution in Archosauria, the group including birds and crocodilians today and dinosaurs, pterosaurs, and basal forms during the Mesozoic, with the aims of shedding light on the evolution of the modern condition and using new methods to make the most accurate estimates, to date, of relative brain size and shape in extinct archosaurs. Because fossils usually preserve only hard parts, a major objective is to make assessments of the brain cavity of extinct archosaurs by reconstructing component soft tissues, which will then provide a basis for functional interpretation. Hypotheses will be tested in the context of the extant phylogenetic bracket (EPB) approach whereby the modern relatives (birds, crocodilians, lizards) of the fossil group (dinosaurs) provide information on the relationship between soft tissues and the signatures they leave on the bones. Pertinent soft tissues (the brain, its coverings, nerves, blood vessels) will be studied in the modern animals using a range of methods, including a novel imaging technique developed in the PI's lab, to discover their bony correlates. Fossil archosaurs will then be surveyed for these signatures. CT scanning of literally dozens of pivotal fossil specimens will be a critical tool in that it will not only provide data on features embedded within the skull but also will yield 3D digital datasets from which highly accurate measurements can be made automatically. A new method to estimate the size and shape of the brain in dinosaurs (GABRA: gross anatomical brain region approximation) will be refined, allowing new scaling studies of relative brain size using the latest statistical techniques. This information will be mapped onto a genealogical tree of archosaurs to assess the adaptive contexts of major transitions in brain conformation by making correlations with broad behavioral and physiological categories. Numerous undergraduate and graduate students will receive technical and analytical training. The project is highly collaborative, involving many paleontologists and experimentalists worldwide. The extensive radiological imaging will require development of refined imaging protocols, standardized analyses, specialized workstations, and bioinformatics innovations to deal with the voluminous multi-format digital data. Internet-based means of not only disseminating the data but also manipulating the data will be essential, and will take place in connection with existing bioinformatics hubs. Given the continual K-12 interest in all things dinosaurian, the attention this project will attract will provide new opportunities to use dinosaurs as tools to teach about science in general, with expected venues being media outlets, school or other public appearances, and the internet.

祖龙的大脑进化：对鸟类和鳄鱼的尺度、功能和现代条件进化的新影响。大脑被公认为是最重要的器官，因此它的神经生物学和进化一直是生物学的核心兴趣。该项目研究原始龙类的大脑进化，包括今天的鸟类和鳄鱼，以及中生代的恐龙，翼龙和基础形式，目的是阐明现代条件的进化，并使用新方法对灭绝的原始龙类的相对大脑大小和形状进行最准确的估计。由于化石通常只保留硬的部分，一个主要目标是通过重建软组织的组成来评估已灭绝的祖龙的脑腔，这将为功能解释提供基础。将在现存系统发育支架（EPB）方法的背景下对假设进行测试，其中化石组（恐龙）的现代亲属（鸟类，鳄鱼，蜥蜴）提供了软组织与它们在骨骼上留下的签名之间关系的信息。相关的软组织（大脑，其覆盖物，神经，血管）将使用一系列方法在现代动物中进行研究，包括PI实验室开发的新型成像技术，以发现它们的骨相关性。然后将对这些特征的化石主龙进行调查。对数十个关键化石标本进行CT扫描将是一个关键工具，因为它不仅可以提供嵌入头骨内的特征数据，还可以产生3D数字数据集，从而可以自动进行高度精确的测量。一种估计恐龙大脑大小和形状的新方法（GABRA：大体解剖脑区近似）将得到改进，允许使用最新的统计技术对相对大脑大小进行新的缩放研究。这些信息将被映射到一个谱系树的祖龙，以评估适应环境的主要转变，在大脑构造的相关性与广泛的行为和生理类别。许多本科生和研究生将接受技术和分析培训。该项目是高度合作的，涉及世界各地的许多古生物学家和实验学家。广泛的放射成像将需要开发完善的成像协议，标准化的分析，专业工作站和生物信息学创新，以处理大量的多格式数字数据。基于互联网的手段不仅传播数据，而且还处理数据，这将是至关重要的，并将与现有的生物信息学中心联系起来。考虑到K-12对所有关于恐龙的事情的持续兴趣，这个项目将吸引的关注将提供新的机会，利用恐龙作为工具来教授一般的科学知识，预计场地是媒体，学校或其他公共场合，以及互联网。