Giant Deep-Sea Protist Produces Bilaterian-like Traces

  title={Giant Deep-Sea Protist Produces Bilaterian-like Traces},
  author={Mikhail V. Matz and Tamara M. Frank and N. Justin Marshall and Edith A. Widder and S{\"o}nke Johnsen},
  journal={Current Biology},
One of the strongest paleontological arguments in favor of the origin of bilaterally symmetrical animals (Bilateria) prior to their obvious and explosive appearance in the fossil record in the early Cambrian, 542 million years ago, is the occurrence of trace fossils shaped like elongated sinuous grooves or furrows in the Precambrian. Being restricted to the seafloor surface, these traces are relatively rare and of limited diversity, and they do not show any evidence of the use of hard… Expand
Discovery of the oldest bilaterian from the Ediacaran of South Australia
The fossil Ikaria wariootia is described, one of the oldest bilaterians identified from South Australia, and it is found that the size and morphology of Ikaria match predictions for the progenitor of the trace fossil Helminthoidichnites—indicative of mobility and sediment displacement. Expand
Ediacaran Ecosystems and the Dawn of Animals
Ichnology may provide remarkable information for our understanding of Ediacaran paleobiology, illuminating aspects such as the earliest evidence of bilaterians and the nature of Ediacaran ecosystems.Expand
Evidence for Cnidaria-like behavior in ca. 560 Ma Ediacaran Aspidella
The first appearance of animals in the geological record is a matter of continuing debate: how deep were the roots of the Cambrian explosion? Molecular clock estimates indicate that the deepestExpand
Point Formation, Newfoundland First evidence for locomotion in the Ediacara biota from the 565 Ma Mistaken
ABSTRACTEvidence for locomotion in the Precambrian fossil record is scant. Reliable Ediacaran trace fossils are all younger than 560 Ma, and consist of relatively simple horizontal burrows and trailsExpand
Bilaterian Burrows and Grazing Behavior at >585 Million Years Ago
The discovery of the oldest bilaterian burrows in shallow-water glaciomarine sediments from the Tacuarí Formation, Uruguay is reported, which unite the paleontological and molecular data pertaining to the evolution of bilaterians, and link bilateralian origins to the environmental changes that took place during the Neoproterozoic glaciations. Expand
The early history of the metazoa—a paleontologist’s viewpoint
In the aggregate, modern data from molecular biology, palaeontology, and comparative embryology/morphology, having been revitalized by the introduction of new microscopy techniques, imply that the hypothesized planktotrophic gastrae-like common ancestor is the least likely of the diverse suggestions on the origins of the Metazoa. Expand
Possible animal-body fossils in pre-Marinoan limestones from South Australia
The Neoproterozoic era was punctuated by the Sturtian (about 710 million years ago) and Marinoan (about 635 million years ago) intervals of glaciation. In South Australia, the rocks left behind byExpand
Penetrative trace fossils from the late Ediacaran of Mongolia: early onset of the agronomic revolution
The existence of the first vertically penetrative trace fossils from the latest Ediacaran are shown: dense occurrences of the U-shaped trace fossil Arenicolites from late Precambrian marine carbonates of Western Mongolia. Expand
ABSTRACT Surface locomotory trace fossils from the Mistaken Point Formation of Newfoundland, dated at ∼ 565 Ma, suggest that organisms capable of controlled locomotion and possessing muscular tissueExpand
A Solution to Darwin's Dilemma: Differential Taphonomy of Ediacaran and Palaeozoic Non-Mineralised Discoidal Fossils
The eldonides, a group of non-mineralised asymmetrical discoidal fossils characterised by a coiled alimentary canal with circumoral tentacles and radially arranged internal lobes, are perhaps theExpand


The problems and potential of using animal fossils and trace fossils in terminal Proterozoic biostratigraphy
Abstract Despite the discovery of soft-bodied megascopic fossils of late Neoproterozoic age at numerous localities world-wide, there has been slow acceptance of their potential for intercontinentalExpand
The earliest fossil record of the animals and its significance
  • G. Budd
  • Biology, Medicine
  • Philosophical Transactions of the Royal Society B: Biological Sciences
  • 2008
A reasonable case can now be made for the extension of the fossil record of at least basal animals (sponges and perhaps cnidarians) to a period of time significantly before the beginning of the Cambrian. Expand
The cambrian evolutionary ‘explosion’ recalibrated
A new paradigm suggests that the ‘explosion’ in the record may have been decoupled from the evolutionary innovation, and the apparent paradox between the sudden appearance of recognisable metazoans and their extended evolutionary history might be explained by a sudden Cambrian increase in body size, which was accompanied by skeletisation. Expand
The Ediacaran emergence of bilaterians: congruence between the genetic and the geological fossil records
The two historical records of life both suggest that although the cradle of Metazoa lies in the Cryogenian, and despite the explosion of ecology that occurs in the Cambrian, it is the emergence of bilaterian taxa in the Ediacaran that sets the tempo and mode of macroevolution for the remainder of geological time. Expand
Fossils, molecules and embryos: new perspectives on the Cambrian explosion.
The distribution of Hox and other developmental control genes among metazoans indicates that an extensive patterning system was in place prior to the Cambrian, and it is likely that much genomic repatterning occurred during the Early Cambrian. Expand
The Proterozoic and Earliest Cambrian Trace Fossil Record; Patterns, Problems and Perspectives1
  • S. Jensen
  • Geology, Medicine
  • Integrative and comparative biology
  • 2003
A clearer picture of the increase in diversity and complexity can be reached by combining trace fossils into broad groups defined both on morphology and interpretation, which focuses attention on looking for similarites between Neoproterozoic and Cambrian trace fossils. Expand
The Late Precambrian fossil Kimberella is a mollusc-like bilaterian organism
This work reconstructs Kimberella as a bilaterally symmetrical, benthic animal with a non-mineralized, univalved shell, resembling a mollusc in many respects, important evidence for the existence of large triploblastic metazoans in the Precambrian and indicates that the origin of the higher groups of protostomes lies well back in the precambrian. Expand
Ediacaran biota: The dawn of animal life in the shadow of giant protists
Abstract Functional, constructional, and preservational criteria led to a reinterpretation of seemingly complex trace fossils and the majority of assumed metazoan body fossils from VendianExpand
The Rise of Animals: Evolution and Diversification of the Kingdom Animalia
Five of the world's leading paleontologists take us on a journey to the most important fossil sites that serve as unique windows to the earliest animal life-including the Ediacara Hills of Australia, the Russian taiga and tundra, the deserts of southwest Africa, and the rugged coasts of Newfoundland. Expand
The Paleoproterozoic megascopic Stirling biota
Abstract The 2.0–1.8-billion-year-old Stirling Range Formation in southwestern Australia preserves the deposits of a siliciclastic shoreline formed under the influence of storms, longshore currents,Expand