Ordovician
Early Paleozoic period
The Ordovician is a geologic period roughly 485 to 444 million years ago, following the Cambrian and preceding the Silurian.
Marine life diversified dramatically during this time, including early fish and abundant invertebrates.
The period ended with a mass extinction event.
As an adjective, Ordovician describes rocks, fossils, or events from this era: Ordovician limestone, Ordovician trilobites.
Extinct marine arthropods
- sea scorpionsExtinct marine arthropod order
- cephalopodsMollusks with tentacles
- brachiopodsStalked marine filter feeders
- echinodermsSpiny-skinned marine invertebrates
mollusks · arthropods · jawless fish · corals · sponges · algae · invertebrates · reefs
Extinct marine arthropods
- brachiopodsStalked marine filter feeders
- cephalopodsMollusks with tentacles
- gastropodsBelly-footed mollusks
- coralsColonial marine invertebrates
tabulate · rugose · fossilization · sedimentation · faunal succession
Expanding into varied areas
- speciationFormation of distinct species
- brachiopodsStalked marine filter feeders
- trilobitesExtinct marine arthropods
- cephalopodsMollusks with tentacles
invertebrates · phylogeny · extinction · ecological niches · predation · mineralization
Early complex-life epoch
- geologicalOf Earth's physical structure
- strataParallel geological layers
- sedimentaryFormed from deposited material
- GondwanaAncient southern supercontinent
glaciation · mass extinction · sea level · limestone · shale · sandstone · carbonate · continental drift
trilobites
Extinct marine arthropods
- sea scorpionsExtinct marine arthropod order
- cephalopodsMollusks with tentacles
- brachiopodsStalked marine filter feeders
echinoderms · mollusks · arthropods · jawless fish · corals · sponges · algae · invertebrates · reefs · biodiversity
trilobites
Extinct marine arthropods
- brachiopodsStalked marine filter feeders
- cephalopodsMollusks with tentacles
- gastropodsBelly-footed mollusks
corals · tabulate · rugose · fossilization · sedimentation · faunal succession
diversification
Expanding into varied areas
- speciationFormation of distinct species
- brachiopodsStalked marine filter feeders
- trilobitesExtinct marine arthropods
cephalopods · invertebrates · phylogeny · extinction · ecological niches · predation · mineralization
Paleozoic
Early complex-life epoch
- geologicalOf Earth's physical structure
- strataParallel geological layers
- sedimentaryFormed from deposited material
Gondwana · glaciation · mass extinction · sea level · limestone · shale · sandstone · carbonate · continental drift · paleoclimate
OrdovicianQuaternary
Last 2.6 million years
Holocene · Cenozoic · modern era · Anthropocene · recent