Paleozoic Era: Quick Facts

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Facts

Also Known As	Palaeozoic Era

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A detailed geologic time scale chart displaying Earth's history from the Hadean Eon over 4.5 billion years ago to the present, organized by eons, eras, periods, epochs, and ages with color-coded columns and corresponding dates in millions of years.

Illustration of an early Silurian coral-stromatoporoid community showing various labeled marine organisms, including corals, bryozoans, brachiopods, crinoids, trilobites, and a nautiloid, arranged on and around a block of seafloor substrate with a scale bar indicating centimeters.

Pennsylvanian coal forest

Cambrian paleogeography

A timeline chart shows major events in plant evolution alongside the geologic time scale, with illustrations of algae, mosses, ferns, ginkgoes, conifers, cycads, and flowering plants marking their first appearances from the Ordovician to the Cenozoic era. Key milestones such as the emergence of early vascular plants and seed plants are labeled with approximate millions of years ago.

A colorful diagram of the geologic time scale shows major eons, eras, and periods, with illustrations of key prehistoric life forms such as bacteria, jellyfish, trilobites, fishes, dinosaurs, mammals, and humans, spanning from 4,000 million years ago to the present. Measurement bars at the top and bottom indicate the passage of time in millions of years, and each section is color-coded to highlight evolutionary milestones.

Cutaway diagram of a Grand Canyon wall showing layered sedimentary rocks-limestone, shale, sandstone, and composite rocks-with labels indicating Paleozoic rocks (about 252-541 million years old) above older Precambrian rocks, which include Proterozoic (541 million to 2.5 billion years old) and Archean (over 2.5 billion years old) layers. The Colorado River is shown at the base.

A chart detailing the Carboniferous period within the Paleozoic era, showing its division into Mississippian and Pennsylvanian subperiods, with corresponding epochs, ages, and their ranges in millions of years ago.

A chart detailing the Devonian period of the Paleozoic era, showing its division into Lower, Middle, and Upper series with stages such as Lochkovian, Pragian, Emsian, Eifelian, Givetian, Frasnian, and Famennian, alongside corresponding ages in millions of years ago.

A chart showing the Ordovician period within the Paleozoic era on the geologic time scale, listing its division into Lower, Middle, and Upper epochs, with corresponding stage names and their ages in millions of years ago.

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Topics

Silurian Period Cambrian Period Devonian Period Ordovician Period Permian Period Carboniferous Period Primary labyrinthodont Blastozoa Paleozoic Erathem Mesozoic Era Cenozoic Era

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Key People

Roderick Impey Murchison

Sir Roderick Impey Murchison

British geologist

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Joachim Barrande

French geologist

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Raymond Cecil Moore

American paleontologist