Ancient steroids establish the Ediacaran fossil Dickinsonia as one of the earliest animals

  title={Ancient steroids establish the Ediacaran fossil Dickinsonia as one of the earliest animals},
  author={Ilya Bobrovskiy and Janet M. Hope and Andrey Ivantsov and Benjamin J. Nettersheim and Christian Hallmann and Jochen J. Brocks},
  pages={1246 - 1249}
The enigmatic Ediacara biota (571 million to 541 million years ago) represents the first macroscopic complex organisms in the geological record and may hold the key to our understanding of the origin of animals. [] Key Result Here, we show that lipid biomarkers extracted from organically preserved Ediacaran macrofossils unambiguously clarify their phylogeny. Dickinsonia and its relatives solely produced cholesteroids, a hallmark of animals. Our results make these iconic members of the Ediacara biota the…

Chemical clues to the earliest animal fossils

Steroid biomarkers show that the Ediacaran fossil Dickinsonia was an animal The Ediacara biota are a diverse assemblage of macroscopic body forms that appear in the sedimentary rock record between

Putative sponge biomarkers in unicellular Rhizaria question an early rise of animals

Fossil lipid biomarkers previously thought to be diagnostic of sponges (and thus indicative of animal life) are found to be preserved in unicellular Rhizarian protists, questioning a pre-Cambrian origin of spongees.

Developmental processes in Ediacara macrofossils

This analysis demonstrates that the genetic pathways for multicellularity, axial polarity, musculature, and a nervous system were likely present in some of these early animals, supporting the hypothesis that these evolved independently in disparate bilaterian clades.

Reconsidering the Role of Animals and Protists During the Neoproterozoic-Cambrian Transition

The wide geographic and stratigraphic occurrence and high relative abundance of these biomarkers in Ediacaran and Cambrian sediments suggests an early emergence, and an important ecological role of demosponges over a 100 Myr period during the pivotal Neoproterozoic-Cambrian transition.

The developmental biology of Charnia and the eumetazoan affinity of the Ediacaran rangeomorphs

The development of Charnia masoni is characterized and the affinity of rangeomorphs is established, among the oldest and most enigmatic components of the Ediacaran macrobiota, and homology and rationalize morphogenesis between disparate rangeomorph taxa are found.

Algal origin of sponge sterane biomarkers negates the oldest evidence for animals in the rock record.

It is demonstrated that C30 24-isopropylcholestane is not diagnostic for sponges and probably formed in Neoproterozoic sediments through the geological methylation of C29 sterols of chlorophyte algae, the dominant eukaryotes at that time.


Abstract: The Ediacara Biota represents a turning point in the evolution of life on Earth, signifying the transition from single celled organisms to complex, community-forming macrobiota. The

Food sources for the Ediacara biota communities

Information is presented on primary producers in the Ediacaran based on biomarker molecules that were extracted from sediments hosting macrofossils and evidence for abundant algal food sources available for these organisms is found.

New holozoans with cellular resolution from the early Ediacaran Weng'an Biota, SW China

Embryo-like fossils from the early Ediacaran Weng'an Biota (SW China, 609 myr ago), widely interpreted as holozoans, potentially provide insights into the early evolutionary development of metazoans

Exceptionally Preserved Cambrian Fossils in the Genomic Era

  • J. Ortega‐Hernández
  • Geography, Environmental Science
    Old Questions and Young Approaches to Animal Evolution
  • 2019
This chapter provides an overview of the significance of exceptionally preserved Cambrian fossils and their contribution towards illuminating the origin of animal body plans.



Highly regulated growth and development of the Ediacara macrofossil Dickinsonia costata

It is shown that development in Dickinsonia costata was surprisingly highly regulated to maintain an ovoid shape via terminal addition and the predictable expansion of modules, suggesting that it does not belong within known animal groups, but that it utilized some of the developmental gene networks of bilaterians.

The advent of animals: The view from the Ediacaran

  • M. DroserJ. Gehling
  • Geography, Environmental Science
    Proceedings of the National Academy of Sciences
  • 2015
It is shown that, although in appearance, these organisms look very strange and unfamiliar, many of them may have had a biology and/or ecology similar to animals today, and some were most certainly bilaterians, cnidarians, and poriferans.

THE EDIACARA BIOTA: Neoproterozoic Origin of Animals and Their Ecosystems

Present evidence suggests that the Ediacara biota included a mixture of stem- and crown-group radial animals, stem-group bilaterian animals, “failed experiments” in animal evolution, and perhaps representatives of other eukaryotic kingdoms.

Affirming life aquatic for the Ediacara biota in China and Australia

The Ediacara biota has been long championed as a snapshot of the marine ecosystem on the eve of the Cambrian explosion, providing important insights into the early evolution of animals. Fossiliferous

A placozoan affinity for Dickinsonia and the evolution of late Proterozoic metazoan feeding modes

It is hypothesized that the affinities of Dickinsonia lie with the Placozoa (Metazoa), an understudied phylum that is widespread in tropical seas worldwide and discusses the potential evolutionary transitions between the main metazoan feeding modes in the context of the emerging molecular phylogeny.

Ediacaran life on land

It is shown that the uppermost surfaces of the palaeosols have a variety of fossils in growth position, including Charniodiscus, Dickinsonia, Hallidaya, Parvancorina, Phyllozoon, Praecambridium, Rugoconites, Tribrachidium and ‘old-elephant skin’ (ichnogenus Rivularites).

Molecular fossils from organically preserved Ediacara biota reveal cyanobacterial origin for Beltanelliformis

The discovery of molecular fossils from organically preserved specimens of Beltanelliformis demonstrate that they represent large spherical colonies of cyanobacteria, revealing that these enigmatic members of the Ediacara biota were benthic colonial cyanob bacteria.

Testing the protozoan hypothesis for Ediacaran fossils: a developmental analysis of Palaeopascichnus

Developmental analysis of the Palaeopascichnus reveals unusual, protozoan features, including evidence for chaotic repair structures, for mergence of coeval forms, as well as complex bifurcations, which suggest that Palaeobiology is a body fossil of an unidentified protozoa but is unrepresentative of Ediacaran body construction, in general.

Sterols in a unicellular relative of the metazoans

The sterol profile of the choanoflagellate Monosiga brevicollis is characterized, a representative of the unicellular sister group of animals, and genomic and biochemical information have been used together to investigate the taxonomic specificity of a fossil biomarker.

Fossil steroids record the appearance of Demospongiae during the Cryogenian period

It is suggested that shallow shelf waters in some late Cryogenian ocean basins contained dissolved oxygen in concentrations sufficient to support basal metazoan life at least 100 Myr before the rapid diversification of bilaterians during the Cambrian explosion.