COLLABORATIVE RESEARCH: Taphonomy, paleoecology, and evolution of mammals and squamates from Egg Mountain: An exceptional view of a Late Cretaceous ecosystem

合作研究：蛋山哺乳动物和有鳞目动物的埋藏学、古生态学和进化：晚白垩纪生态系统的独特视角华盛顿大学格雷戈里·威尔逊，蒙大拿州立大学大卫·瓦里基奥，纽约理工学院杰克·康拉德现代哺乳动物和蜥蜴起源于恐龙阴影下的白垩纪（1.45 - 66亿年前）地质时期。然而，这些小体型群体的化石记录很差，阻碍了对它们早期进化的清晰理解。最近在蒙大拿州两个医学形成（蛋山）的一个长期闲置的恐龙地点进行的挖掘产生了丰富的，保存非常完好的，大部分未运输的两个群体的化石。蛋山已经贡献了更多相对完整的哺乳动物和蜥蜴的头骨和骨骼，比北美任何其他地区相同的地质时代。我们的研究将调查这些新标本的繁殖历史、进化历史和生态。通过这种综合的方法，我们将研究独特的蛋山组合的生态意义，哺乳动物和蜥蜴如何在这些古老的生态系统中分配资源，以及晚白垩世（1亿至6600万年前）哺乳动物和蜥蜴的系统发育和生态多样性模式。通过纳入更完整的骨骼，这项研究将澄清我们对这些群体进化历史的理解，描述现代哺乳动物和蜥蜴化石亲属的生态学特征，并揭示晚白垩世（1亿至6600万年前）陆地生态系统的性质以及古代哺乳动物和蜥蜴的多样性和地理分布。综合的方法加上一个特殊的化石组合将大大增加我们对陆地生态系统结构和动态的理解，并为研究具有较大化石样本量的同一地质时期保存较差的遗骸的其他地方提供信息。拟议中的研究有望产生重大见解，影响科学界和更广泛的公众。这些研究结果将通过结果的出版、本科生和研究生的培训以及通过博物馆项目的公共宣传来传播。在PI中，有两个早期的职业科学家，他们都是代表性不足的少数民族（一个拉丁美洲人和一个美洲原住民），在研究生中，一个是第一代大学生和美国退伍军人。

COLLABORATIVE RESEARCH: Taphonomy, paleoecology, and evolution of mammals and squamates from Egg Mountain: An exceptional view of a Late Cretaceous ecosystemGregory Wilson, University of WashingtonDavid Varricchio, Montana State UniversityJack Conrad, New York Institute of TechnologyModern mammals and lizards had their origins in the Cretaceous (145-66 million years ago) geological period within the shadow of the dinosaurs. However, the poor fossil record of these small-bodied groups has hindered a clear understanding of their early evolution. Recent excavation at a long idle dinosaur locality in the Two Medicine Formation of Montana (Egg Mountain) has produced abundant, exceptionally well-preserved and largely un-transported fossils of both groups. Already, Egg Mountain has contributed more relatively complete skulls and skeletons of mammals and lizards than any other locality of the same geologic age in North America. Our research will investigate the preservational history, the evolutionary history, and the ecologies of these new specimens. Through this integrative approach, we will investigate the ecological significance of the unique Egg Mountain assemblage, how mammals and lizards partitioned resources in these ancient ecosystems and the pattern of phylogenetic and ecologic diversification within Late Cretaceous (100-66 million years ago) mammals and lizards. With the incorporation of more complete skeletons, this research will clarify our understanding of the evolutionary history of these groups, characterize the ecology of fossil relatives of modern mammals and lizards, and shed light on the nature of Late Cretaceous(100-66 million years ago) land-based ecosystems and the diversification and geographic distribution of ancient mammals and lizards. The integrated approach together with an exceptional fossil assemblage will greatly increase our understanding of land based ecosystem structure and dynamics and inform studies on other localities with large fossil sample sizes of more poorly preserved remains of the same geologic time period. The proposed research promises to lead to major insights that will impact the scientific community and the broader public. These findings will be disseminated via publication of results, training for undergraduates and graduate students, and public outreach through museum programs. Among the PIs, there are two early career scientists, both of whom are underrepresented minorities (one Latino and one Native American), and among the graduate students, one is a first-generation college student and U.S. military veteran.