Ediacaran Period, 635-543 million years ago
(The animals illustrated here date primarily from 565-550 mya)
Clade Petalonamae†
- Rangeomorphs and relatives
- Uncertain if they are animals
- Generally have a quilted body plan, with no internal organs
- May be stalked (leaf-like) or lie flat on sediments (worm-like)
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Charnia sp. fossil replica (Clade Rangeomorpha)
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Charniodiscus sp. fossil (Clade Rangeomorpha)
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Life models of various Petalonamae
See also identification labels. All are clade Rangeomorpha and from Ediacaran Period except where indicated otherwise.
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Clade Proarticulata†
- Segmented animals with "gliding asymmetry" (segments offset at midline)
- Generally with an anterior head shield
Clade Trilobozoa†
- Disk-like animals with triradial symmetry
- Raised ridges aided in suspension feeding
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Dickinsonia costata fossil (Clade Proarticulata)
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Life models of Ediacaran Proarticulata.
See also with identification labels.
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Life models of the Ediacaran Trilobozoans Tribachidium (left) and Albumares (right).
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Other Ediacaran Organisms
- Some are likely members of modern phyla while others are enigmatic and may not even be animals
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Life models of possible Ediacaran Cnidaria (the phyla of Inaria (2nd from left) and Mawsonites (far right) are debated).
See also with identification labels.
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Life models of Ediacaran representatives of other extant phyla/clades.
See also with identification & phylum labels.
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Life models of some Ediacaran organisms of unknown relationships (not to scale).
See also with identification labels.
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Cambrian Fossils
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Elrathia kingi trilobite (Wheeler Formation, Utah)
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Agnostid trilobite, Ptychagnostus sp. (Wheeler Formation, Utah)
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Eocrinoid fossil, Gogia palmeri/juvalorum (Spence Shale, ID)
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Cyanobacteria, Morania fragmenta and Green Algae, Yuknessia simplex? fossils
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Cambropallas telesto trilobite fossil (Morocco)
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Hyolithid fossil, Nevadotheca (Emigrant Springs Formation, NV)
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Syspacephalus longus trilobite fossil (Groom Range, NV)
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Pikaia gracilens fossil cast (Burgess Shale, BC)
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Opabinia regalis fossil cast (Burgess Shale, BC)
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Leanchoilia sp. arthropod fossil (Chengjiang Biota, China)
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Palaeoscolex sinensis worm fossil (Chengjiang Biota, China)
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Haikouella lanceolata chordate (stem vertebrate) fossil (Chengjiang Biota, China)
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