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The Nama Group of Namibia and South Africa preserves an extraordinary record of marine ecosystems existing in the lastc. 15 myr of the Ediacaran, comprising enigmatic and soft-bodied fossils that are part of the first major radiation of macroscopic life. Since their description at the beginning of the 20th century these fossils have played an important role in debates surrounding the affinities of iconic Ediacaran fossil groups, and ash beds preserved throughout the succession have been crucial to understanding rates and patterns of early animal evolution. Fossils preserved in varying contexts have allowed for detailed reconstructions of Ediacaran palaeobiology, and geochemical analyses provide a window into understanding the controls on Ediacaran taphonomic pathways, including crucial, and potentially widespread, roles played by clay minerals in exceptional fossil preservation.
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Ancient life and moving fluids
ABSTRACT Over 3.7 billion years of Earth history, life has evolved complex adaptations to help navigate and interact with the fluid environment. Consequently, fluid dynamics has become a powerful tool for studying ancient fossils, providing insights into the palaeobiology and palaeoecology of extinct organisms from across the tree of life. In recent years, this approach has been extended to the Ediacara biota, an enigmatic assemblage of Neoproterozoic soft‐bodied organisms that represent the first major radiation of macroscopic eukaryotes. Reconstructing the ways in which Ediacaran organisms interacted with the fluids provides new insights into how these organisms fed, moved, and interacted within communities. Here, we provide an in‐depth review of fluid physics aimed at palaeobiologists, in which we dispel misconceptions related to the Reynolds number and associated flow conditions, and specify the governing equations of fluid dynamics. We then review recent advances in Ediacaran palaeobiology resulting from the application of computational fluid dynamics (CFD). We provide a worked example and account of best practice in CFD analyses of fossils, including the first large eddy simulation (LES) experiment performed on extinct organisms. Lastly, we identify key questions, barriers, and emerging techniques in fluid dynamics, which will not only allow us to understand the earliest animal ecosystems better, but will also help to develop new palaeobiological tools for studying ancient life.
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- Award ID(s):
- 2007928
- PAR ID:
- 10454581
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Biological Reviews
- Volume:
- 96
- Issue:
- 1
- ISSN:
- 1464-7931
- Page Range / eLocation ID:
- p. 129-152
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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