Time Frame

The Mesozoic Era is an interval of geological time from about 248 million years ago to about 65 million years ago.

Changes in Continents

At the start of the Mesozoic, the continents were all joined together forming one large continent called Pangaea. During Mesozoic time, they pulled apart from one another, pangaea broke apart into the continents we have today due to plate tectonics.
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Major Evolutionary Events

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,penis-dinosaurs became extinct at the end of the Cretaceous. Some of the last dinosaurs to have lived are found in the late Cretaceous deposits of Montana in the United States.
The Mesozoic was also a time of great change in the terrestrial vegetation. The early Mesozoic was dominated by ferns, cycads, ginkgophytes, bennettitaleans, and other unusual plants. Modern gymnosperms, such as conifers, first appeared in their current recognizable forms in the early Triassic. By the middle of the Cretaceous, the earliest angiosperms had appeared and began to diversify, largely taking over from the other plant groups.

Mass Extinction Causes and Impacts on Life on Earth

  • 95% of life on Earth died out and started the Mesozoic era (meaning "middle life") that spanned 187 million years.
  • This extinction event was possibly caused by the Siberian Traps volcanic event, an asteroid impact, methane hydrate gasification, sea level fluctuations, a major anoxic event, other events, or some combination of these events.

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APA SOURCES

History of the Earth. (2012, March 4). In Wikipedia, The Free Encyclopedia. Retrieved 19:36, March 6, 2012, from http://en.wikipedia.org/w/index.php?title=History_of_the_Earth&oldid=480209260

Polly, D. (15/6). University of california museum of paleontology. Retrieved from March 6, 2012, from http://www.ucmp.berkeley.edu/mesozoic/mesozoic.php


Windows into the universe. (n.d.). Retrieved from http://www.windows2universe.org/earth/geology/hist_mesozoic.html