Mesozoic Era: Quick Facts

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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.

Pangea: Early Triassic Period

Pangea: Late Jurassic Period

Late Cretaceous paleogeographic map

Illustration showing various dinosaur species drawn to scale and grouped by geologic era: Late Cretaceous, Early Cretaceous, Jurassic, and Triassic. Dinosaurs range from large species like Brachiosaurus and Tyrannosaurus to smaller ones like Velociraptor and Compsognathus, with a human silhouette included for size comparison. Measurement bars at the bottom indicate 1 meter and 3 feet for scale reference.

Map of the northern Yucatan Peninsula in Mexico highlighting the location and circular outline of the Chicxulub crater, which is about 180 kilometers in diameter and partly extends into the Gulf of Mexico. The map also shows nearby cities such as Merida, Cancun, Campeche, and Playa del Carmen, as well as international borders with Belize and Guatemala. An inset globe marks the region's location in the Americas.

Chicxulub crater

computer-generated image of the Chicxulub crater

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 chart showing the Cretaceous period of the Mesozoic era on the geologic time scale, listing its division into Upper and Lower epochs, with stages such as Maastrichtian, Campanian, and Berriasian, and corresponding ages in millions of years ago.

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Topics

Triassic Period Cretaceous Period Jurassic Period dinosaur rudist Stromatoporoidea Secondary Mesozoic Erathem phylloceratid Cycadeoidales Cenozoic Era Paleozoic Era

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Key People

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George Gaylord Simpson

American paleontologist

Mantell, detail of an engraving

Gideon Algernon Mantell

British paleontologist

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