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This document describes a new theory concerning the ascendancy and the extinction of the dinosaurs during the Mesozoic Era of approximately 225 to 65 million years ago. The geologic time scale of the Mesozoic Era is subdivided into three periods. These periods are:

  • TRIASSIC PERIOD about 225 to 193 million years ago. During this period the earliest dinosaurs appeared, displacing many of the existing reptiles.
  • JURASSIC PERIOD about 193 to 136 million years ago. During this period the diversity and physical size of dinosaurs increased tremendously. The larger terrestrial dinosaurs such as Allosaurus, Brachiosaurus, Diplodocus and Stegosaurus appeared.
  • CRETACEOUS PERIOD about 136 to 65 million years ago. During this period, especially in its early segment, the large dinosaurs were gradually replaced by smaller dinosaurs such as the boneheaded pachycephalosaurus, Triceratops and Oviraptosaurs. By the end of this period, all of the known non-avian dinosaurs appear to have become extinct.

Many theories have been introduced to explain the extinction of the dinosaurs.
Briefly, some of these are:

  • A large extra-terrestrial body (such as a meteor) struck the Earth’s surface around 65 million years ago at the K-T (Cretaceous/Tertiary) boundary throwing up a worldwide cloud of soot and debris. This effectively caused a dramatic cooling of the Earth’s surface which created an environment in which the dinosaurs could not survive.
  • Massive worldwide volcanic activity occurred at the K-T boundary due to the Earth’s increased plate tectonic activity, having the same effect as an extra-terrestrial collision.
  • The widespread expansion of flowering plants and trees caused the blanketing of the Earth’s atmosphere with pollen creating an environment that was hostile to the dinosaurs.
  • Massive cosmic ray activity destroyed the dinosaurs.

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? 2004, John Stojanowski. All Rights Reserved.

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