Triassic Period

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Triassic Period Dinosaur

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The Triassic period emerged in the Earth’s history at the time when Triassic dinosaurs were evolved. The period was followed by the Jurassic period and the Cretaceous period. At the end of the Cretaceous period, the dinosaurs were wiped out in a mass extinction event along with the majority of all other life. 

As a period of geological time, the boundaries of the Triassic are defined based on the rocks found and fossil records. It was the German geologist Friedrich August von Alberti who first introduced the Triassic period. It got its name because this period of geologic time is represented by a three-part division of rock type in Germany. These three different rock layers are (from the bottom to the earliest) the Bunter ( which is a red bead and brown sandstone), the Muschelkalk, and the Keuper. These types of rock are found in local areas, but not globally.

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When did Triassic Era Begin?

The Triassic era began 250 million years ago and ended 201 million years ago. The period before the Triassic era is known as the Permian. This was the time when the different varieties of animals lived, including a group of animals known as synapsids which later evolve into mammals. One member of this group was a large, sail-backed animal known as the dimetrodon, which looks like a dinosaur but was not.

Further, the  Permian-Triassic extinction event occurred 250 million years ago. This was the largest extinction event our planet has ever observed. During this period, 70% of the species on the land disappeared along with 95% of those in the oceans. This was not only the beginning of the Triassic era and the ending of the Permian period, but it was such a serious catastrophe that it is used as a marker of the end of the geological era, the Paleozoic era.

Triassic Period Animals 

Some scientists believe mammals evolved from a group of extinct mammals- like reptiles, Theriodontia, which were Therapsids.. These mammals were tiny and considered to have been nocturnal. The earliest - known turtle Proganochelys, also appeared during the Late Triassic. 

The Triassic animals like turtles, frogs, salamanders, lizards (including sphenodontia & snakes), and pterosaurs first appeared during the Triassic. Insects during the Triassic period begin to undergo complete metamorphosis from larva through pupa to adult.

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Triassic Jurassic Extinction

Triassic Jurrasic extinction also, known as the end Jurassic extinction is a glocal extinction event that occurred at the end of the Triassic period (about 252 million to 201 million years ago) that resulted in the expiration of some 76% of all marine and terrestrial species and about 20% of all taxonomic families. It is observed that the end of the Jurassic extinction was the significant moment that enabled dinosaurs to become the dominant land animal on Earth. 

The end-Triassic extinction specifically affected the ammonoids and conodonts. These are the two groups that serve as important index fossils for assigning relative ages to different strata in the Triassic System of rocks. Only the phylloceratid ammonites were able to survive during the Triassic extinction, and they gave rise to the explosive radiation of cephalopods later in the Jurassic Period. Furthermore, varied families of bivalves, gastropods, brachiopods, and marine reptiles also became extinct.

A large part of the vertebrate fauna on land disappeared, although the dinosaurs, pterosaurs, crocodiles, turtles, mammals, and fishes were minimally affected by the transition. In fact, most of the authorities maintain that the end-Triassic mass extinction on land opened ecological niches that were filled relatively quickly by dinosaurs. Plant fossils and palynomorphs (a microscopic fossil composed of especially pollen or grains) exhibit no significant changes in diversity across the Triassic-Jurassic boundary.

Triassic Extinction

The end of the Triassic period initiates with a massive extinction followed by massive volcanic eruptions about 208-213 million years ago. The supercontinent Pangea began to break apart. 35% of all the family's animals die out, including labyrinthodont amphibians, conodonts, and all marine reptiles except ichthyosaurs.

Most of the synapsid reptiles, which had governed the Permian and early Triassic period, were dead (excluding mammals). Most of the early, primitive dinosaurs were also dead, but other, more adaptive dinosaurs developed in the Jurassic. 

Nobody is sure what causes the late Triassic extinction. The possibilities are global cooling or an asteroid impact. A 210 million-year-old meteor crater surrounding Manicouagan Reservoir, Quebec, Canada, maybe the remains of the culprit.

This extinction enables many dinosaurs to expand into different fields that were unoccupied. Dinosaurs would become increasingly commanding, plentiful, diverse, and lived the same way for the next 150 million years. The Jurrasic and Cretaceous was the true “ Age of Dinosaurs” rather than the Triassic.

Did You Know?

  • The triassic period had 3 epochs, the Early triassic, the middle triassic, and the Late triassic.

  • The Triassic period observed a rise in the dinosaurs, and they would rule the planet for the next 185 million years.

  • The Triassic period started with the Permian Triassic extinction event and ended with the Triassic Jurassic extinction event.

  • The dinosaurs that lived during the Triassic period were Melanorosaurus, Plateosaurus, Thecodontosaurus, and the Staurikosaurus.

  • The Triassic period lasted about 50.6 million years.

  • The shortest period of the Mesozoic era was the Triassic period. 

  • The Triassic period is the first of the three geological periods of the Mesozoic era.

FAQ (Frequently Asked Questions)

1. How was the Overall Climate During the Triassic Period?

Ans. The overall climate during the Triassic period was quite different as of today.

  • The Triassic period had about 80% of today's oxygen level.

  • Carbon dioxide during the Triassic period was six times in the air as there was before the industrial revolution.

  • The average surface temperature of Earth was about 3° hotter than it is now.

2. From where did the Name Triassic Come From?

Ans. The name Triassic originates from the three rock strata that formed during the Triassic period. Three layers of rock strata that formed during this period are:

  • Red beds, rest in the desert condition.

  • Limestone, rest in the seas, mostly over the continental shelf, and

  • Black slate, rest in rich organic conditions such as River Delta.

3. When were the Triassic, Jurassic, and Cretaceous Periods?

Ans. The Triassic period from 252 million to 250 million years ago saw the rise of reptiles and the first dinosaur. While the Jurrasic Period from about 200 million to 145 million years ago, saw the rise in birds and mammals. And the Cretaceous period from about 145 million to 65 million years ago is renowned for its iconic dinosaurs, such as the Triceratops and Pterosaurs such as Pteranodon.