New Mammals from Early Cretaceous and Their Implications for Deep Mammalian Phylogeny

美国匹兹堡卡内基自然历史博物馆（Carnegie Museum of Natural History）的罗哲喜博士获得了一笔资助，用于研究一些保存精美的中国哺乳动物化石，这些化石是通过与中国科学家的国际合作提供的。这些来自早白垩纪羽毛恐龙遗址的哺乳动物化石大约有1.25亿年的历史。它们代表了已知最早的现代有袋动物（如负鼠和袋鼠）和胎盘动物（如鲸鱼、蝙蝠、狗和人类）的近亲。有袋类动物和胎盘类动物占所有现存哺乳动物的99.9%；它们在新生代（距今6500万年）统治着世界。罗博士计划对这些哺乳动物化石的头骨和骨骼进行广泛的进化研究，以确定现代有袋动物和胎盘动物起源的祖先解剖学条件。他还将尝试通过对这些化石的系统发育研究来重建主要哺乳动物群体的家谱。罗博士计划的研究将建立的家谱和解剖进化模式将为了解所有哺乳动物的最早历史提供洞见。人类是灵长类动物；灵长类动物是胎盘动物；胎盘与存在于中生代的许多已灭绝的哺乳动物组成的巨大的进化灌木嵌套在一起。因为更好地了解早期哺乳动物的历史可以给我们自己的存在赋予意义，所以早期哺乳动物历史的研究成果可以引起强烈的公众兴趣，并将对公共科学教育有用。这项研究将有助于罗博士作为博物馆馆长的科普工作和对公众的进化论教育。研究成果将通过通俗讲座和通俗科学出版物进行传播。一些有新闻价值的发现通过这个nsf支持的项目也可以通过新闻媒体传达给全球观众。对中生代哺乳动物的研究也可以纳入卡内基博物馆计划在未来几年举办的新恐龙展览。这项NSF项目还将使罗博士能够培养哺乳动物进化生物学的研究生和本科生，并将最新的研究成果纳入他在匹兹堡大学的教学中。

A grant has been awarded to Dr. Zhe-Xi Luo of Carnegie Museum of Natural History in Pittsburgh to study some exquisitely preserved fossil mammals from China, made available through an international collaboration with the Chinese scientists. These fossil mammals from the Early Cretaceous Feathered Dinosaur sites are about 125 million years old. They represent the earliest known relatives to modern marsupials (such as opossums and kangaroos) and placentals (such as whales, bats, dogs, and humans). Marsupials and placentals collectively make up 99.9% of all living mammals; and they have dominated the world in the Cenozoic (65 million years to the present). Dr. Luo plans to conduct an extensive evolutionary study of the skull and skeleton of these fossil mammals in order to establish the ancestral anatomical conditions from which modern marsupials and placentals are derived. He will also attempt a reconstruction of the family tree for major groups of mammals through the phylogenetic studies of these fossils. The family tree and the pattern of anatomical evolution to be established by Dr. Luo's planned studies will provide insight into the earliest history of all mammals.Humans are primates; primates are placentals; placentals are nested with a vast evolutionary bush of many extinct mammals that existed in the Mesozoic. Because a better understanding of early mammalian history can give meaning to our own existence, research findings in the early mammalian history can generate strong public interest, and will be useful for public science education. This research will be helpful for Dr. Luo to popularize science as a museum curator and to educate the public about evolution. The research findings will be disseminated by popular lectures and popular scientific publications. Some newsworthy discoveries made through this NSF-supported project can also be conveyed to a global audience through news media. Research on Mesozoic mammals can also be incorporated into the Carnegie Museum's new dinosaur exhibits scheduled for the next several years. This NSF project will also enable Dr. Luo to train graduate and undergraduate students in mammalian evolutionary biology, and to incorporate the latest research findings in his teaching at the University of Pittsburgh.