1] Department of Natural History-Palaeobiology, Royal Ontario Museum, 100 Queen's Park, Toronto, Ontario, Canada M5S 2C6 [2] Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario, Canada M5S 3B2 [3] Department of Earth Sciences, University of Toronto, 25 Russell Street, Toronto, Ontario, Canada M5S 3B1.
Geology Department, Pomona College, 185 E. Sixth Street, Claremont, California 91711, USA.
Nat Commun. 2014;5:3210. doi: 10.1038/ncomms4210.
Burgess Shale-type fossil assemblages provide the best evidence of the 'Cambrian explosion'. Here we report the discovery of an extraordinary new soft-bodied fauna from the Burgess Shale. Despite its proximity (ca. 40 km) to Walcott's original locality, the Marble Canyon fossil assemblage is distinct, and offers new insights into the initial diversification of metazoans, their early morphological disparity, and the geographic ranges and longevity of many Cambrian taxa. The arthropod-dominated assemblage is remarkable for its high density and diversity of soft-bodied fossils, as well as for its large proportion of new species (22% of total diversity) and for the preservation of hitherto unreported anatomical features, including in the chordate Metaspriggina and the arthropod Mollisonia. The presence of the stem arthropods Misszhouia and Primicaris, previously known only from the early Cambrian of China, suggests that the palaeogeographic ranges and longevity of Burgess Shale taxa may be underestimated.
伯吉斯页岩型化石组合为“寒武纪大爆发”提供了最佳证据。在这里，我们报告了在伯吉斯页岩中发现的一个非凡的新的软体动物群。尽管与沃尔科特的原始产地相距不远（约 40 公里），但大理石峡谷化石组合是独特的，为后生动物的最初多样化、它们早期的形态差异以及许多寒武纪分类群的地理范围和寿命提供了新的见解。以节肢动物为主的组合以其高密度和多样化的软体化石为特征，还有大量的新物种（占总多样性的 22%），以及迄今未报道的解剖特征的保存，包括脊索动物 Metaspriggina 和节肢动物 Mollisonia。以前只在中国早寒武世发现的原始节肢动物 Misszhouia 和 Primicaris 的存在表明，伯吉斯页岩分类群的古地理范围和寿命可能被低估了。
