Closing the African Gap-Cretaceous and Paleogene Paleontology in the Rukwa Rift Basin, Southwestern Tanzania

亚赤道非洲的化石记录是检验一系列基本古生物地理学假设的关键。由国家地理学会资助的五次对坦桑尼亚西南部鲁夸河裂谷盆地的考察（2002-06）揭示了新的白垩纪和古近纪陆生脊椎动物的多样性。这些发现增加了重要的新数据，直接关系到冈瓦纳脊椎动物地理学的竞争性假设，在第三纪的过渡。该补助金汇集了一个国际和跨学科的团队，以描述盆地中白垩纪和古近纪沉积物中的新动物群。新的化石将被放置到一个严格的系统发育框架，和彻底的地质分析鲁夸河裂谷盆地存款将允许分类群在时间和古环境的背景下进行解释。新发现的化石将用于检验有关冈瓦纳脊椎动物进化和分布的地理学假设，并在美国和坦桑尼亚展出供公众教育。智力优势：该领域包括在一个有限的地理区域内的第三纪边界的两侧。这强调了该地区的重要性，为测试古生物地理学假说的起源和分布冈瓦纳脊椎动物在地质和生物动态时期，从白垩纪到第三纪早期。到目前为止，只有一小部分的沉积矿床在盆地内进行了勘探。在2004/2005年，勘测发现了两个新的露头区域，其中包含保存完好的化石。根据这项赠款，更大的船员和更长的探险将导致更多的新发现。这项资助的主要科学目标是：1）继续在已探明的地点进行工作; 2）扩大搜索范围，包括未勘探的裂谷盆地地层; 3）对该地区进行完整的盆地分析，描绘地层的地层、沉积学和沉积框架，以更好地限制沉积物的年龄; 4）对新化石进行详细的解剖学和系统发育学研究，并利用这些数据来评估有关中生代晚期和第三纪早期脊椎动物进化的相互竞争的地理学假设。更广泛的影响：该团队将通过以下方式在坦桑尼亚和美国开发学术人力资源：1）在达累斯萨拉姆大学提供短期课程讲座; 2）通过与该项目相关的实地，实验室和研究传播活动，将美国学生的培训与坦桑尼亚同行联系起来; 3）开发一个巡回展览，突出主要发现和古生物学发现和研究的过程。该展览将为坦桑尼亚服务严重不足的观众提供非正式的科学学习资源，同时为美国学生和教师提供一个旨在吸引科学和普通观众的技能发展论坛。

The fossil record of sub-equatorial Africa holds keys for testing a range of fundamental paleobiogeographic hypotheses. Five expeditions (2002-06) to the Rukwa Rift Basin in southwestern Tanzania funded by the National Geographic Society have revealed a diversity of new Cretaceous and Paleogene terrestrial vertebrates. These discoveries add crucial new data that bear directly on competing hypotheses concerning Gondwanan vertebrate biogeography during the Cretaceous-Tertiary transition. This grant assembles an international and interdisciplinary team to characterize novel faunas from Cretaceous and Paleogene deposits in the basin. New fossils will be placed into a rigorous phylogenetic framework, and thorough geological analysis of Rukwa Rift Basin deposits will allow taxa to be interpreted in both temporal and paleoenvironmental contexts. New fossil discoveries will be used to test biogeographic hypotheses concerning the evolution and distribution of Gondwanan vertebrates and exhibited for public education in both the USA and Tanzania. Intellectual Merit: The field area encompasses both sides of the Cretaceous-Tertiary boundary within a restricted geographic area. This underscores the significance of the region for testing paleobiogeographic hypotheses concerning the origin and distribution of Gondwanan vertebrates during the geologically and biologically dynamic period from the Cretaceous into the early Tertiary. To date, only a fraction of the sedimentary deposits within the basin have been explored. In 2004/5, reconnaissance surveys identified two new outcrop areas that contain well-preserved fossils. The larger crews and longer expeditions under this grant will result in additional new discoveries. The primary scientific goals of this grant are: 1) to continue working proven localities; 2) to expand the search area to include unexplored rift basin strata; 3) to perform a complete basin analysis of the area, delineating the stratigraphic, sedimentologic, and depositional framework of the strata, to better constrain the age of the deposits; and 4) to conduct detailed anatomical and phylogenetic studies of new fossils and use these data to assess competing biogeographic hypotheses concerning the evolution of late Mesozoic and early Tertiary vertebrates. Broader Impact:The team will develop academic human resources in both Tanzania and the United States by: 1) offering short course lectures at the University of Dar es Salaam; 2) linking the training of US students with their Tanzanian peers through field, laboratory, and research dissemination activities related to the project; and 3) developing a traveling exhibit highlighting the major finds and the process of paleontological discovery and research. This exhibit will enhance informal science learning resources for greatly underserved audiences in Tanzania, while giving US students and faculty a forum for developing skills aimed at engaging scientific and general audiences alike.