The Triassic Period

All the continents were joined together as one huge continent, known as Pangaea. When it started to break up towards the end of this period into two continents, the one in the south is known as Gondwanaland. The map shows what Pangea was like, but the continents of today have been drawn on so we can see where they were. If you look at the south, you can see what is now Australia.

Click here to read about Pangaea and Gondwanaland

At the beginning of the Triassic period, there was the largest extinction of species ever known. About 95% of all species became extinct. The cause is not known, but may have been results of the movement of the continents together, a cooling of the world or volcanic eruptions together with poisonous gases. So during the Triassic period there was the appearance of many new forms of life.

There were no dinosaurs at the start of the Triassic period, but there were many amphibians and some reptiles. In the seas, corals appeared and ammonites reappeared. On land, the plants were mainly seed plants and conifers.

In the late Triassic, the first mammals appeared. They were tiny, about the size of mice, and probably nocturnal (active at night). The first turtles appeared, as well as frogs, salamanders, lizards and snakes. The dinosaurs were small, and most were quite similar. Pterosaurs, or flying reptiles, appeared during the late Triassic. Insects began to undergo metamorphosis to turn into adults. Marine reptiles appeared.

In the plant world, cycads became plentiful.

The climate in the Triassic period was hot and dry, causing desert-like conditions. There were seasonal heavy rains however, forming rivers and lakes during the wet season. The polar regions were moist and mild.

The end of the Triassic period is also marked by a mass extinction. Pangaea was beginning to break apart, there were huge volcanic eruptions and about 35% of animal species died out. Most of the early dinosaurs became extinct, but some were able to adapt and evolved further during the Jurassic period.


Some Dinosaurs of the Triassic Period  

If you use any part of this, acknowledge it in your bibliography like this:
Sydenham, S. & Thomas, R. The Triassic Period [Online] (2002).

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updated October 2013©