CAREER: Taphonomy and Evolution of Theropod Dinosaur Reproduction

职业：埋藏学和兽脚类恐龙繁殖的进化

• 批准号: 0847777
• 负责人: David Varricchio
• 金额: $ 59.09万
• 依托单位: Montana State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2015-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0847777&HistoricalAwards=false
• 关键词: CAREER; Taphonomy; Evolution; Theropod; Dinosaur

TAPHONOMY AND EVOLUTION OF THEROPOD DINOSAUR REPRODUCTION David J. Varricchio Reproduction in living birds differs markedly from that of other modern vertebrates in the rate of egg production, egg size and shape, microscopic structure of the eggshell, nest form, method of incubation, and the manner and prevalence of parental care. The disparity between birds and other living vertebrates raises questions as to how and when this unique reproductive style evolved. Did it originate before or after the achievement of flight? Were the carnivorous theropod dinosaurs from which birds evolved reproductively more similar to their dinosaur relatives or to modern birds? How important were the reproductive and life history strategies of Mesozoic dinosaurs to their success? The proposed research addresses these questions by documenting the evolution of reproductive traits through the Mesozoic from dinosaurs to birds. The investigation consists of four phases: 1) study of modern bird and crocodile nesting localities for attributes that would help interpret dinosaur sites, 2) investigation of Cretaceous theropod dinosaur nesting sites, 3) construction of an evolutionary history of reproductive traits based on field, laboratory, and museum study and 4) comparison of the life history strategies among theropod dinosaurs, other dinosaurs, and living egg-laying vertebrates. Strengths of this study include an interdisciplinary team with expertise in taphonomy (the study of fossil preservation), eggshell structure, and the nesting behavior of modern birds, as well as an unsurpassed suite of modern and fossil samples. Modern nesting localities represent both crocodilians and birds that exhibit a wide array of reproductive behaviors. The Mesozoic dinosaur sample includes four egg types from the Cretaceous of Montana and Idaho; these four egg types represent the only in place theropod dinosaur eggs from North America. The study of modern nesting horizons provides the framework for interpreting fossil nesting localities. Data generated from the studies of modern crocodilians and birds will allow recognition of patterns and processes affecting fossil preservation. The combination of extensive fieldwork, laboratory analysis of eggs, and the exceptional fossil sample will provide new insights on egg preservation and the reproductive behavior of theropod dinosaurs. Identification of new egg characters and resolution of controversial issues regarding theropod reproductive behavior will strengthen our evolutionary understanding. Documentation of the evolutionary history of reproduction in birds and their theropod dinosaurs ancestors, will provide insight into the origination of birds. Comparison of modern and extinct life history strategies among crocodilians, dinosaurs, and birds will increase current understanding of dinosaur ecology, test life history theory on a macroevolutionary scale, and permit evaluation of factors potentially contributing to the overall success of dinosaurs throughout the Mesozoic. Educational goals include incorporation of research observation and interpretation into university courses and professional development for rural Montana science teachers through workshops and fieldwork participation. Additionally, the project will support research opportunities for two masters and eight undergraduate students. Finally, Varricchio serves as host committee chair for the 4th International Symposium on Dinosaur Eggs and Babies to be held at Montana State University in the summer of 2009. This meeting provides an excellent opportunity for dissemination of the research results, while facilitating greater exchange of ideas between biologists and paleontologists regarding the evolution of bird and dinosaur reproduction.

兽脚亚目恐龙繁殖的埋藏学和进化 David J. Varricchio 现存鸟类的繁殖与其他现代脊椎动物的繁殖在产蛋率、蛋大小和形状、蛋壳微观结构、巢穴形式、孵化方法和父母照顾的方式和普遍性。鸟类和其他现存脊椎动物之间的差异引发了关于这种独特的繁殖方式如何以及何时进化的问题。它是在实现飞行之前还是之后产生的？鸟类从繁殖进化而来的肉食性兽脚亚目恐龙是否与其恐龙亲戚或现代鸟类更相似？中生代恐龙的繁殖和生活史策略对其成功有多重要？拟议的研究通过记录中生代从中生代恐龙到鸟类的生殖特征的演变来解决这些问题。该调查包括四个阶段：1）研究现代鸟类和鳄鱼的筑巢地点，寻找有助于解释恐龙遗址的属性，2）调查白垩纪兽脚亚目恐龙筑巢地点，3）基于实地构建生殖特征的进化历史，实验室和博物馆研究；4）兽脚亚目恐龙、其他恐龙和现存卵生脊椎动物生活史策略的比较。这项研究的优势包括拥有埋藏学（化石保存研究）、蛋壳结构和现代鸟类筑巢行为方面专业知识的跨学科团队，以及一套无与伦比的现代和化石样本。现代筑巢地点代表了鳄鱼和鸟类，它们表现出广泛的繁殖行为。中生代恐龙样本包括来自蒙大拿州和爱达荷州白垩纪的四种恐龙蛋；这四种蛋是北美唯一现存的兽脚亚目恐龙蛋。 现代筑巢地平线的研究为解释化石筑巢地点提供了框架。现代鳄鱼和鸟类研究产生的数据将有助于识别影响化石保存的模式和过程。广泛的实地考察、蛋的实验室分析和特殊的化石样本相结合，将为蛋的保存和兽脚亚目恐龙的繁殖行为提供新的见解。鉴定新的卵特征并解决有关兽脚类繁殖行为的有争议的问题将加强我们对进化的理解。对鸟类及其兽脚亚目恐龙祖先繁殖进化史的记录，将有助于深入了解鸟类的起源。鳄鱼、恐龙和鸟类的现代和灭绝生活史策略的比较将增加目前对恐龙生态学的理解，在宏观进化尺度上测试生活史理论，并允许评估可能有助于整个中生代恐龙整体成功的因素。教育目标包括将研究观察和解释纳入大学课程，以及通过研讨会和实地考察参与蒙大拿州农村科学教师的专业发展。此外，该项目还将支持两名硕士生和八名本科生的研究机会。最后，Varricchio 担任将于 2009 年夏季在蒙大拿州立大学举行的第四届恐龙蛋和恐龙宝宝国际研讨会的主办委员会主席。这次会议为传播研究成果提供了绝佳的机会，同时促进了更多的思想交流生物学家和古生物学家之间关于鸟类和恐龙繁殖进化的讨论。