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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