Collaborative Research - Mesozoic Therians From Central Asia: The Basal Radiation Of Tribosphenic Mammals And Their Impact On The Higher-Level Relationships Of Therian Mammals

合作研究 - 来自中亚的中生代兽类：三颅哺乳动物的基础辐射及其对兽类哺乳动物高级关系的影响

• 批准号: 0129127
• 负责人: John Wible
• 金额: $ 4.9万
• 依托单位: Carnegie Institute
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-02-01 至 2005-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0129127&HistoricalAwards=false
• 关键词: Collaborative; Research; Mesozoic; Therians; Central

Collaborative Research - Mesozoic therians from Central Asia: the basal radiation of tribosphenic mammals and their impact on the higher-level relationships of therian mammals A grant has been awarded to Dr. Novacek at the American Museum of Natural History, Dr. Rougier at the University of Louisville, and Dr. Wible at the Carnegie Museum of Natural History for a comprehensive study of the Cretaceous (145 to 65 million-years-ago) radiation of therian mammals. Therians include living marsupials and placentals plus their extinct relatives. Therians are represented today by more than 4600 species accounting for nearly all the diversity of living mammals, the exception being the three species of egg-laying monotremes. The study of the evolutionary relationships among therians has been addressed with data from molecular biology (the structure of DNA) and comparative anatomy (the structure of living and extinct forms). The family trees (phylogenies) that result from these two approaches are not entirely congruent nor do they suggest the same time of origin of the major lineages of living therians. However, both molecular and anatomical workers agree that insectivore-like forms are at the base of the therian radiation. Available to Drs. Novacek, Rougier, and Wible as the core study group for their project are exquisitely preserved, 80 million-year-old insectivore-like fossils, some related to placentals and others to marsupials, collected from the famed dinosaur and fossil mammal beds of Mongolia's Gobi Desert by recent joint expeditions from the American Museum and the Mongolian Academy of Sciences. Unlike the vast majority of Cretaceous therian fossils, which are merely isolated jaws and teeth, these are nearly complete skeletons. They will provide the most comprehensive anatomical data base to date for studying the evolutionary relationships among Cretaceous therians and their living descendants, and evaluating the controversial difference between DNA and anatomical results. Most of the Cretaceous therians to be studied are shrew-sized and, therefore, cannot effectively be investigated with the naked eye alone. Two tools are needed for the anatomical study of these small forms: standard stereoscopic microscopy and high-resolution computer tomographic imaging (CT-scanning). Both are available, the latter at a National Science Foundation supported facility at Pennsylvania State University. Drs. Novacek, Rougier, and Wible will use their expertise in the anatomy of living and extinct mammals, and the collections at the American Museum, Carnegie Museum, and other institutions to build an anatomical data base of comparative information. Family trees will be generated from this data base by various available computer programs and compared with those previously published based on other information. These exquisite Mongolian fossils are a unique resource that ultimately will be returned to their country of origin. Careful study and extensive documentation of these fossils now is critical in order to make them widely accessible for scientific advancement. A by-product of this study will be a standardized anatomical terminology for the therian skeleton; currently, researchers studying particular therian lineages employ different terms that are often incongruent. This study also affords the opportunity for educating and training of new scientists at both the pre- and postdoctoral level. Finally, the valuable scientific knowledge contained in these fossils will be translated for the public through the exhibits and educational programs of the American Museum and Carnegie Museum.

Collaborative Research - Mesozoic therians from Central Asia: the basal radiation of tribosphenic mammals and their impact on the higher-level relationships of therian mammals A grant has been awarded to Dr. Novacek at the American Museum of Natural History, Dr. Rougier at the University of Louisville, and Dr. Wible at the Carnegie Museum of Natural History for a comprehensive study of the Cretaceous (145 to 65 million-years-ago) radiation Therian哺乳动物。 Therians包括活着的有袋动物和胎盘以及其灭绝的亲戚。今天，有4600多种物种代表了Therians，这些物种几乎占活性哺乳动物的多样性，例外是三种单卵单体。从分子生物学（DNA的结构）和比较解剖结构（生存和灭绝形式的结构）中，对Therians之间的进化关系的研究已得到解决。这两种方法引起的家族树（系统发育）并不完全一致，也没有提出同一时间的起源，这是活着的Therians的主要血统。然而，分子和解剖工人都同意类似昆虫的形式在Therian辐射的底部。可用于Drs。 Novacek，Rougier和Wible是其项目的核心研究小组，已保存完好，拥有8000万历史的类似昆虫的化石，有些与胎盘和其他有关的化石与有袋动物有关，这些化石与最近的联合探险是从美国的Gobi Deserts from American American Museum和Mongolian的Mogongolian Consemencence和Mornongolian的Mongolian Contections从蒙古的Gobi沙漠中收集的。与仅仅是孤立的下颌和牙齿的绝大多数白垩纪Therian化石不同，它们几乎是完整的骨骼。他们将提供迄今为止最全面的解剖数据库，以研究白垩纪Therians及其生物后代之间的进化关系，并评估DNA和解剖学结果之间有争议的差异。大多数要研究的白垩纪Terrians都是精明的，因此不能仅用肉眼进行有效研究。这些小型形式的解剖学研究需要两种工具：标准的立体显微镜和高分辨率计算机断层扫描成像（CT扫描）。 两者都可以使用，后者在宾夕法尼亚州立大学的国家科学基金会支持设施中。博士。 Novacek，Rougier和Wible将在生命和灭绝的哺乳动物解剖结构中使用他们的专业知识，以及美国博物馆，卡内基博物馆和其他机构的收藏来建立比较信息的解剖学数据库。 家族树将通过各种可用的计算机程序从此数据库中生成，并与其他基于其他信息发布的计算机程序相比。这些精致的蒙古化石是一种独特的资源，最终将返回其原籍国。现在，仔细研究和对这些化石的大量文献对使其可用于科学发展至关重要。 这项研究的副产品将是Therian骨骼的标准化解剖学术语。目前，研究特定谱系的研究人员采用了通常不一致的不同术语。 这项研究还为在学前和博士后层面教育和培训新科学家提供了机会。最后，这些化石中包含的宝贵科学知识将通过美国博物馆和卡内基博物馆的展览和教育计划来为公众翻译。