Paleobiology of a Uniquely Well-Preserved Window on the Early Evolution of Multicellular Organisms

9805032克诺尔化石记录了生命历史的前85%，主要是微观的。只有在过去的5.44亿年里，大型动物的遗骸才变得丰富，后来植物的遗骸变得丰富，这使得地质学家将这一时期命名为显生代--可见生命的时代。连接这些截然不同的时代的关键事件是复杂的多细胞进化。多细胞生物在动物、真菌和几类藻类中至少出现了六次。一些化石表明，多细胞红色、绿色和稻草藻(棕色和相关的)藻类在10亿年前就存在了。多细胞生物可能在微小的祖先动物中出现得相当早，但到目前为止，古生物学家认为任何埃迪卡拉纪之前的动物记录都是无法获得的。一个引人注目的化石沉积物现在为多细胞生物的早期多样化提供了前所未有的新线索。有6-5.5亿年历史的陡山坨组中国磷灰岩含有三维保存的化石，记录了在前寒武纪岩石中发现的早期生命，确实是任何时代最重要的化石沉积之一。与北京大学张云教授合作，研究小组将从我们之前的研究表明是化石的地方收集大量材料。新的、可能有生产潜力的地点也将在实地进行抽样。样品将在实验室中制备，并通过光学和电子显微镜进行研究。预计这项研究将为理解生命历史上的一次重大转变提供一个新的经验性、古生物学框架。

9805032KnollFossils that document the first 85 percent of the history of life are predominantly microscopic. Only in the last 544 million years have the remains of large animals and, later, plants become abundant, leading geologists to christen this interval the Phanerozoic Eon -- the age of visible life. The key event that connects these strikingly different eras is the evolution of complex multicellularity. Multicellular organisms arose at least six times in animals, fungi, and several groups of algae. A handful of fossils suggest that multicellular red, green, and stramenopile (brown and related) algae existed a billion years ago. Multicellularity may have arisen comparably early in tiny ancestral animals, but until now any pre-Ediacaran animal record was thought to be inaccessible to paleontologists.A remarkable fossil deposit is now shedding unprecedented new light on the early diversification of multicellular organisms. Phosphorites of the 600-550 million year old Doushantuo Formation, China, contain three-dimensionally preserved fossils that record of early life yet discovered in Precambrian rocks; indeed, they must rank among the most important fossil deposits of any age.A two-year research project is proposed to investigate the systematic paleontology and paleobiology of multicellular fossils in the Doushantuo phosphorites. In collaboration with Professor Zhang Yun of Beijing University, the research team will collect large volumes of material from localities that our previous research has shown to be fossiliferous. New, potentially productive4 localities will also be sampled in the field. Samples will be prepared in the laboratory and studied by light and electron microscopy. It is anticipated that this research will provide a new empirical, paleontological framework for understanding a major transition in the history of life.