Discovery of bilaterian-type through-guts in cloudinomorphs from the terminal Ediacaran Period

Schiffbauer, James D.; Selly, Tara; Jacquet, Sarah; Merz, Rachel; Nelson, Lyle L.; Strange, Michael A.; Cai, Yao; Smith, Emily F.

doi:10.1038/s41467-019-13882-z

Cited by 56 publications

(59 citation statements)

References 71 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The affinity of these (and the majority of) organisms of Ediacaran age remains controversial. However, when interpreted as metazoans, they are generally regarded as cnidarian-or poriferan-grade animals, but see Schiffbauer et al (2020) for an alternative interpretation of some cloudinomorph fossils. The fossils of this period exhibit a range of mineralogies in their skeletons.…”

Section: The Evidence For the Early Evolution Of Animal Skeletonsmentioning

confidence: 99%

“…Similarly mineralized tubes of vestimentiferan worms first occur much later in the Palaeozoic (Himmler et al, 2008), with superficial similarities with various Ediacaran and Cambrian tubular fossils. An annelid affinity for some cloudinomorph fossils has also been supported recently by putative soft tissues interpreted as guts (Schiffbauer et al, 2020). However, given these cloudinomorph fossils and vestimentiferan tubes have complex, different taphonomic histories and are peculiar to restricted environments (Haas et al, 2009), a close affinity is not well supported.…”

Section: The Evidence For the Early Evolution Of Animal Skeletonsmentioning

confidence: 99%

See 1 more Smart Citation

The ‘biomineralization toolkit’ and the origin of animal skeletons

Murdock

2020

Biological Reviews

112

View full text Add to dashboard Cite

Biomineralized skeletons are widespread in animals, and their origins can be traced to the latest Ediacaran or early Cambrian fossil record, in virtually all animal groups. The origin of animal skeletons is inextricably linked with the diversification of animal body plans and the dramatic changes in ecology and geosphere–biosphere interactions across the Ediacaran–Cambrian transition. This apparent independent acquisition of skeletons across diverse animal clades has been proposed to have been driven by co‐option of a conserved ancestral genetic toolkit in different lineages at the same time. This ‘biomineralization toolkit’ hypothesis makes predictions of the early evolution of the skeleton, predictions tested herein through a critical review of the evidence from both the fossil record and development of skeletons in extant organisms. Furthermore, the distribution of skeletons is here plotted against a time‐calibrated animal phylogeny, and the nature of the deep ancestors of biomineralizing animals interpolated using ancestral state reconstruction. All these lines of evidence point towards multiple instances of the evolution of biomineralization through the co‐option of an inherited organic skeleton and genetic toolkit followed by the stepwise acquisition of more complex skeletal tissues under tighter biological control. This not only supports the ‘biomineralization toolkit’ hypothesis but also provides a model for describing the evolution of complex biological systems across the Ediacaran–Cambrian transition.

show abstract

Section: The Evidence For the Early Evolution Of Animal Skeletonsmentioning

confidence: 99%

Section: The Evidence For the Early Evolution Of Animal Skeletonsmentioning

confidence: 99%

The ‘biomineralization toolkit’ and the origin of animal skeletons

Murdock

2020

Biological Reviews

112

View full text Add to dashboard Cite

show abstract

“…Cloudinids in siliciclastic-dominated beds of the Wood Canyon Formation, Nevada, show more spatially restricted framboidal pyritization that preserves cylindrical internal structures recently interpreted as possible digestive tracts ( 17 ). Internal digestive tissue is otherwise completely unknown from the Ediacaran record although common in Cambrian Lagerstätten ( 17 ). In sum, the processes operating in this preservational setting have created a taphonomically unique Lagerstätte.…”

Section: Discussionmentioning

confidence: 99%

Ediacaran metazoan reveals lophotrochozoan affinity and deepens root of Cambrian Explosion

et al. 2021

View full text Add to dashboard Cite

Through exceptional preservation, we establish a phylogenetic connection between Ediacaran and Cambrian metazoans. We describe the first three-dimensional, pyritized soft tissue in Namacalathus from the Ediacaran Nama Group, Namibia, which follows the underlying form of a stalked, cup-shaped, calcitic skeleton, with six radially arranged lobes projecting into an apical opening and lateral lumens. A thick body wall and probable J-shaped gut are present within the cup, and the middle layer of the often-spinose skeleton and skeletal pores are selectively pyritized, supporting an organic-rich composition and tripartite construction with possible sensory punctae. These features suggest a total group lophotrochozoan affinity. These morphological data support molecular phylogenies and demonstrates that the origin of modern lophotrochozoan phyla, and their ability to biomineralize, had deep roots in the Ediacaran.

show abstract

“…Few feeding appendages or internal digestive structures have been recognized in Ediacaran organisms (e.g. Fedonkin et al ., 2007; Schiffbauer et al ., 2020), although this may be in part due to taphonomic biases (see Wade, 1968; Norris, 1989; Liu et al ., 2011; Gibson, Schiffbauer, & Darroch, 2018). Consequently, the mechanisms by which many Ediacaran groups fed remain unclear.…”

Section: Ediacaran Palaeobiology and Palaeoecologymentioning

confidence: 99%

Ancient life and moving fluids

et al. 2020

View full text Add to dashboard Cite

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.

show abstract

Discovery of bilaterian-type through-guts in cloudinomorphs from the terminal Ediacaran Period

Cited by 56 publications

References 71 publications

The ‘biomineralization toolkit’ and the origin of animal skeletons

The ‘biomineralization toolkit’ and the origin of animal skeletons

Ediacaran metazoan reveals lophotrochozoan affinity and deepens root of Cambrian Explosion

Ancient life and moving fluids

Contact Info

Product

Resources

About