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The Mesozoic Era is the era of Earth's geological history, lasting from about 252 to 66 million years ago, comprising the Triassic, Jurassic and Cretaceous Periods. It is characterized by the dominance … Wikipedia
Factsheet
Etymology
Name formality Formal
Nickname(s) Age of Reptiles, Age of Dinosaurs, Age of Conifers
Factsheet
Etymology
Name formality Formal
Nickname(s) Age of Reptiles, Age of Dinosaurs, Age of Conifers
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Wikipedia
en.wikipedia.org › wiki › Mesozoic
Mesozoic - Wikipedia
2 weeks ago - This era began in the wake of the Permian–Triassic extinction event, the largest mass extinction in Earth's history, and ended with the Cretaceous–Paleogene extinction event, another mass extinction whose victims included the non-avian dinosaurs, pterosaurs, mosasaurs, and plesiosaurs.
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Encyclopedia Britannica
britannica.com › science › earth science, geologic time & fossils › fossils & geologic time
Mesozoic Era | Geology, Climate & Lifeforms | Britannica
July 26, 1999 - Its name is derived from the Greek term for “middle life.” The Mesozoic Era began 252.2 million years ago, following the conclusion of the Paleozoic Era, and ended 66 million years ago, at the dawn of the Cenozoic ...
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Australian Museum
australian.museum › learn › dinosaurs › mesozoic-era
The Mesozoic era - The Australian Museum
What an ending. We know the outcome, but what was the cause? Can we really know what happened 66 million years ago? And why does it matter today? The Mesozoic came to an abrupt end 66 million years ago in a dramatic extinction event.
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USGS
usgs.gov › youth-and-education-in-science › mesozoic
Mesozoic | U.S. Geological Survey
Mesozoic (252-66 million years ago) means 'middle life' and this is the time of the dinosaurs. This era includes the Triassic, Jurassic, and Cretaceous Periods, names that may be familiar to you.
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Scienceviews
scienceviews.com › dinosaurs › mesozoic.html
The Mesozoic Era
The event that caused the transition from the Paleozoic era to the Mesozoic era was the greatest extinction this earth has seen. This extinction wiped out about 95% of all marine life and 70% of land-life. This allowed the dinosaurs to step in and settle into their role as the lords of the earth. The era ended with "The Great Extinction" which marked the end of the dinosaurs as the Cenozoic era began.
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Live Science
livescience.com › planet earth › geology
Mesozoic era: Age of the dinosaurs | Live Science
July 28, 2022 - The Mesozoic era was bookended by two great extinctions, with another smaller extinction occurring at the end of the Triassic period, Olsen said.
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Study.com
study.com › science › earth science › geology › geological history of earth
Mesozoic Era Overview, Timeline & Facts - Lesson | Study.com
October 8, 2015 - The Mesozoic era lasted for approximately 186 million years. The entirety of the Mesozoic era began approximately 252 million years ago, and ended approximately 66 million years ago in Earth's geological ...
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EBSCO
ebsco.com › research-starters › earth-and-atmospheric-sciences › mesozoic-era
Mesozoic Era | Research Starters | EBSCO Research
The era ended with significant extinction events, which led to the disappearance of many Mesozoic species, including most dinosaurs, marking the transition to the subsequent Cenozoic Era.
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Britannica Kids
kids.britannica.com › students › article › Mesozoic-Era › 329878
Mesozoic Era - Students | Britannica Kids | Homework Help
Its position as the second of the ... approximately 252 million years ago at the close of the Paleozoic Era and ended 66 million years ago at the dawn of the Cenozoic Era....
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Geosciences LibreTexts
geo.libretexts.org › campus bookshelves › fullerton college › introduction to geology (ikeda) › 8: earth history
8.5: Mesozoic Era - Geosciences LibreTexts
August 22, 2024 - Similar to the end of the Paleozoic era, the Mesozoic Era ended with the K-Pg Mass Extinction (previously known as the K-T Extinction; "K" = Cretaceous and "Pg" = Paleogene) 66 million years ago [136]. This extinction event was likely caused ...
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Fossils-uk
fossils-uk.com › blog › prehistoric-periods-what-was-the-mesozoic-era
Prehistoric Periods: What Was The Mesozoic Era? | FossilsUK | Blog
June 18, 2025 - The Mesozoic Era ended much like it began, with a mass extinction event wiping out most life on the planet.
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Fossilicious
fossilicious.com › mesozoic-era.html
Mesozoic Era: Facts, Timelines & Animals
The Mesozoic Era started and ended with mass-extinctions, with DINOSAURS sandwiched in-between. Through in a side of marine reptiles and flowering plants.
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GeoKansas
geokansas.ku.edu › mesozoic-era
Mesozoic Era | GeoKansas
Dinosaurs appeared and disappeared during the Mesozoic Era, which lasted 186 million years and encompasses three periods: the Cretaceous, Jurassic, and Triassic. During the first part of the era, much of the surface in Kansas was being eroded. If dinosaurs lived in Kansas then, they weren't ...
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University of California Museum of Paleontology
ucmp.berkeley.edu › mesozoic › mesozoic.html
Introduction to the Mesozoic Era
Mesozoic means "middle animals", and is the time during which the world fauna changed drastically from that which had been seen in the Paleozoic. Dinosaurs, which are perhaps the most popular organisms of the Mesozoic, evolved in the Triassic, but were not very diverse until the Jurassic. Except for birds, dinosaurs became extinct at the end of the Cretaceous.
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Geosciences LibreTexts
geo.libretexts.org › bookshelves › geology › an introduction to geology (johnson, affolter, inkenbrandt, and mosher) › 8: earth history
8.7: Mesozoic - Geosciences LibreTexts
August 25, 2025 - Note the large spike at the end of the Cretaceous (labeled as K). Similar to the end of the Paleozoic era, the Mesozoic Era ended with the K-Pg Mass Extinction (previously known as the K-T Extinction) 66 million years ago [136]. This extinction ...
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ScienceDirect
sciencedirect.com › topics › earth-and-planetary-sciences › mesozoic-era
Mesozoic Era - an overview | ScienceDirect Topics
The Mesozoic Era (252–66 Ma) spread over an interesting time that witnessed splitting of the Pangaea supercontinent and the opening and spreading of the Atlantic and Indian oceans. It brackets the time interval sandwiched between two extreme events of biodiversity crisis i.e., the end Permian ...
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U.S. National Park Service
nps.gov › articles › 000 › mesozoic-era.htm
Mesozoic Era (U.S. National Park Service)
The Mesozoic Era (251.9 to 66.0 million years ago) was the "Age of Reptiles." During the Mesozoic, Pangaea began separating into the modern continents, and the modern Rocky Mountains rose.
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University of California Museum of Paleontology
ucmp.berkeley.edu › mesozoic › mesozoic.php
The Mesozoic Era
Mesozoic means "middle animals," and is the time during which the world fauna changed drastically from that which had been seen in the Paleozoic. Dinosaurs, which are perhaps the most popular organisms of the Mesozoic, evolved in the Triassic, but were not very diverse until the Jurassic. Except for birds, dinosaurs became extinct at the end of the Cretaceous.
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8TH-GRADE SCIENCE
science8sc.weebly.com › mesozoic-era.html
Mesozoic Era - 8TH-GRADE SCIENCE
Small mammals came into existence, and birds evolved from the dinosaurs. ​ Another mass extinction marked the end of the Mesozoic Era, whether triggered by a giant asteroid or comet impact, volcanic ...