Extraordinary adaptations
Bizarre Cambrian Animals: 12 Extraordinary Body Plans
Five-eyed Opabinia, spiny Hallucigenia and shield-headed Cambroraster reveal the unfamiliar shapes of Cambrian seas. Explore their anatomy through linked fossil-based records.
Explore the animals 12 ↘
How this list was selected
An editorial selection of animals assigned to the Cambrian in the atlas, emphasizing contrasting anatomy rather than size. Soft-bodied fossil deposits preserve details that are usually lost. Reconstructions and evolutionary relationships have changed as new specimens were studied. These animals are not ranked by evolutionary advancement.
In this guide 12
Explore the animals
12 atlas records
About 508 million years ago
Opabinia
Opabinia regalis
Five eyes and a grasping proboscis made this small swimmer one of the Cambrian’s strangest forms.
Laurentian shallows · Present-day Canada
About 508 million years ago
Hallucigenia
Hallucigenia sparsa
Paired spines guarded a soft-bodied walker once reconstructed upside down.
Laurentian and South China shallows
About 521–508 million years ago
Anomalocaris
Anomalocaris canadensis
A meter-long swimmer with grasping frontal appendages was a giant of Cambrian seas.
Laurentian shallows · Present-day Canada
About 508 million years ago
Wiwaxia
Wiwaxia corrugata
Rows of scales and long spines armored this small seafloor grazer.
Laurentian shallows · Present-day Canada
About 508 million years ago
Marrella
Marrella splendens
Two pairs of curved head spines, long antennae and dozens of fine legs made this two-centimeter arthropod exquisitely elaborate.
Offshore slope of Laurentia · Burgess Shale, Canada
About 506 million years ago
Cambroraster
Cambroraster falcatus
A horseshoe-shaped carapace and rake-like appendages made a mobile sediment sifter.
Muddy seafloor · Canada
About 506 million years ago
Titanokorys
Titanokorys gainesi
An enormous head shield covered most of this bottom-feeding radiodont.
Continental-slope seafloor · Canada
About 508 million years ago
Nectocaris
Nectocaris pteryx
Paired fins, a funnel and tentacle-like appendages form one of the Cambrian's most puzzling swimmers.
Open marine water column · Canada
About 508 million years ago
Hurdia
Hurdia victoria
A huge domed carapace covered its head, giving this radiodont the outline of a tiny finned submarine.
Open continental shelf · Present-day Canada and western USA
About 508 million years ago
Aysheaia
Aysheaia pedunculata
Ten pairs of stubby legs beneath a soft body place it near the early history of velvet worms and arthropods.
Laurentian outer shelf · Burgess Shale, Canada
About 508 million years ago
Leanchoilia
Leanchoilia superlata
A pair of great appendages ended in three long whips that could sense, seize and move food.
Deep shelf mud · Burgess Shale, Canada
About 508 million years ago
Odaraia
Odaraia alata
A broad bivalved shell enclosed most of the body and a three-pronged tail steered it.
Open shallow-water column · Canada
