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

9805032 Knoll记录生命史前85%的化石主要是显微镜下的。 只有在最近的5.44亿年里，大型动物的遗骸和后来的植物才变得丰富起来，这使得地质学家将这段时间命名为中生代Eon -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多细胞生物的进化。 多细胞生物在动物、真菌和几种藻类中至少出现了六次。 少数化石表明，多细胞的红色、绿色和层状（棕色和相关）藻类在10亿年前就存在了。 多细胞生物可能很早就出现在微小的祖先动物身上，但直到现在，古生物学家都认为埃迪卡拉纪之前的任何动物记录都是无法获得的。一个引人注目的化石存款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。 陡山沱组磷块岩中保存着迄今为止在前寒武纪岩石中发现的早期生命化石，是世界上最重要的古生物化石矿床之一。 研究小组将与北京大学的张云教授合作，从我们以前的研究表明是丰富的地方收集大量材料。 还将在实地对新的、具有生产潜力的地点4进行抽样调查。 样品将在实验室制备，并通过光学和电子显微镜进行研究。 预计这项研究将提供一个新的经验，古生物学框架，了解生命史上的一个重大转变。

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.