The exceptionally preserved Fezouata Biota from the Lower Ordovician of Morocco: a unique window into the Cambro-Ordovician faunal transition

摩洛哥下奥陶统保存完好的Fezouata生物群：寒武纪-奥陶纪动物群过渡的独特窗口保存完好的生物群，不仅保存了海洋动物的硬壳，还为生命史提供了重要的见解。这样的生物群在寒武纪时期的岩石中相对常见，但我们对奥陶纪之后的生命的认识，几乎完全是基于贝壳的证据。随着摩洛哥东南部Fezouata生物群的发现，这种情况得到了极大的改善。第一个早奥陶世的化石组合在一个正常的，开放的海相环境中保存得非常完好。这些奥陶纪动物表现出相当大的多样性，包括大量的寒武纪伯吉斯页岩型沉积的典型形式，以及更现代的生物。这些发现表明，在中寒武纪之后，伯吉斯页岩型化石的明显消失并不是灭绝和替代的结果，而只是反映了它们在奥陶系岩石中保存的合适环境的稀缺性。摩洛哥的新发现表明，寒武纪的动物特征在2000多万年后的奥陶纪继续对海洋群落的生物多样性和生态产生相当大的影响。此外，Fezouata生物群中出现了许多先进的动物，如马蹄蟹，表明这些群体的辐射比我们所知道的要早得多，在奥陶纪开始之前。摩洛哥的新发现将使我们能够探索寒武纪（寒武纪大爆发）和随后的奥陶纪辐射（奥陶纪生物多样性大事件）期间主要动物群体的多样化是单独的事件，还是仅仅是同一过程的延续。此外，我们将进行实地考察和标本分析，以确定沉积环境和导致软体化石保存的过程，使我们能够预测未来可能在哪里发现新的例子。该项目将为研究生提供独特的学习机会，通过跨学科的研究，在一个壮观的海外领域曝光。它将丰富非专业本科生的生命史课程和研究生的特殊保存课程。这些摩洛哥化石将在耶鲁皮博迪自然历史博物馆进行临时展览，并在博物馆网页上向公众开放。它们将继续吸引更广泛的媒体的注意。该项目将涉及与来自许多国家的研究人员和学生的合作。

The exceptionally preserved Fezouata Biota from the Lower Ordovician of Morocco: a unique window into the Cambro-Ordovician faunal transitionDerek Briggs, EAR-1053247Yale UniversityABSTRACTExceptionally preserved biotas, which preserve more than just the hard shells of marine animals, offer critical insights into the history of life. Such biotas are relatively common in rocks of Cambrian age, but our knowledge of life during the period that follows, the Ordovician, is almost entirely based on the evidence of shells alone. This situation has improved dramatically with the discovery of the Fezouata Biota in south-eastern Morocco ? the first early Ordovician exceptionally preserved fossil assemblage from a normal, open marine setting. These Ordovician animals show considerable diversity and contain a large number of forms typical of older Cambrian Burgess Shale-type deposits as well as more modern looking creatures. These findings show that the apparent disappearance of Burgess Shale-type fossils after the Middle Cambrian is not a result of extinction and replacement, but simply a reflection of the rarity of suitable settings for their preservation in Ordovician rocks. New discoveries in Morocco indicate that animals characteristic of the Cambrian continued to have a considerable impact on the biodiversity and ecology of marine communities more than 20 million years later, into the Ordovician. In addition, the presence of a number of advanced animals, like horseshoe crabs, in the Fezouata Biota indicates that these groups radiated much earlier than we knew, before the beginning of the Ordovician. The new Moroccoan discoveries will allow us to explore whether the diversification of major animal groups during the Cambrian (the Cambrian Explosion) and the subsequent Ordovician radiation (the Great Ordovician Biodiversification Event) were separate events, or simply a continuation of the same process. In addition we will carry out field-work and analyses of specimens to determine the environments of deposition and processes leading to the preservation of the soft-bodied fossils, allowing us to predict where new examples are likely to be found in the future. The project will provide unique learning opportunities for graduate students through interdisciplinary research in an overseas area of spectacular exposure. It will enrich courses on the history of life for non-major undergraduates and on exceptional preservation for graduates. The Moroccan fossils will be the subject of a temporary exhibit at the Yale Peabody Museum of Natural History, and of Museum webpages for the general public. They will continue to attract the attention of the wider media. The project will involve collaboration with researchers and students from many nations.