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| INTRODUCTION TO THE WEBSITE | |
| SETTING THE SCENE | |
| WHAT IS A MASS EXTINCTION? | |
| CAUSES OF MASS EXTINCTIONS | |
| ECOLOGY OF THE TRIASSIC | |
| EVIDENCE OF EXTINCTION |
The Triassic period lasted from 251 to 200 million years ago. It was originally named the Trias in 1834 by the geologist Friedrich August Von Alberti, as in Germany the period consisted of 3 rock types (tri meaning 3). At the top of the youngest of these beds there is evidence for a Mass Extinction which occurred approximately 200 million years ago. The end Triassic was one of the 'BIG FIVE' extinction events to hit the planet in it's history, reducing the number of living families by 35%. Many Paleontologists argue that the event made it possible for the dinosaur group the diapsids, to take over from the dominant species in the Triassic the Synapsids (or mammal like reptiles). There is much current discussion as to whether there was a single extinction event in the Triassic or more than one. There is however no question that there was a mass extinction at the end of the Triassic (Benton 1993). There is clear evidence that the ammonids and bivalves were decimated and that the conodonts were finally pushed to extinction as well as the last of the basal archosaurs. The Triassic period was a time of great change with new groups of animals appearing, many of which are still with us today, including the first turtle, a possible distant ancestor of birds, and the first true mammal our ancestor. Yet the Triassic period would have looked very alien to us, with no grass, and to our eyes a very strange fauna. The formation of Pangea had changed the face of the globe, and created mountain ranges that caused huge rain shadows, which in turn created vast deserts. The climate of the time was also dissimilar, very hot, with warm temperate polar conditions.
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| THEORIES ON THE TRIASSIC MASS EXTINCTION | |
| GEOLOGICAL TIME SCALE | |
| GLOSSARY | |
| OTHER RELATED SITES. |
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