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These sea creatures first
appeared 415 million years ago in the form of a small straight
shelled creature, known as Bacrites. They quickly evolved into a
variety of shapes and sizes including some shaped like hairpins.
During their evolution the ammonites faced no less than three
catastrophic events that would eventually lead to their extinction.
The first event occurred during the Permian (250 million years ago),
where only 10% survived. These surviving species went on to
flourish throughout the Triassic, however at the end of this period
(206 million years ago) they faced near extinction, when all but one
species survived. This event marked the end of the Triassic and the
beginning of the Jurassic, during which time the number of Ammonite
species grew once more. The final catastrophe occurred at the end
of the Cretaceous period when all species were annihilated and the
Ammonites became extinct. This event apparently coincided with the
death of the dinosaurs.
These are collector specimens with limited availability.
For more detailed information
of these specimens please click below.
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