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11 terms

Geologic Record

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Archaean Eon
Origin of Earth
Oldest known rocks on Earth's surface
Oldest fossils of cells (prokaryotes) appear
Concentration of atmospheric oxygen begins to increase
Proterozoic Eon/Ediacaran Period
Oldest fossils of eukaryotic cells appear/diverse algae and soft-bodied invertebrate animals appear
Cambrian Period
Sudden increase in diversity of many animal phyla (Cambrian explosion)
Ordovician Period
Marine algae abundant
Colonization of land by diverse fungi, plants, and animals
Silurian
Diversification of early vascular plants
Devonian
Diversification of bony fishes
First tetrapods and insects appear
Carboniferous
Extensive forests of vascular plants form
First seed plants appear
Origin of reptiles
Amphibians dominant
Permian
Radiation of reptiles
Origin of most present-day groups of insects
Extinction of many marine and terrestrial organisms at end of period
Triassic
Cone-bearing plants (gymnosperms) dominate the landscape
Dinosaurs evolve and radiate
Origin of mammals
Jurassic
Gymnosperms continue as dominant plants
Dinosaurs abundant and diverse
Cretaceous
Flowering plants (angiosperms) appear and diversify
Many groups of organisms, including most dinosaurs, become extinct at the end of the period