OrcasTriassicPeriodPage

__**The Triassic Period**__  248-206 million years ago **Why Did I Pick This Period?**

I picked the Triassic Period to do my project on for many reasons. This time period seemed really interesting to me. It was the time when a lot of animals appeared for the first time. For example, the first dinosaurs evolved in this time period. Also the first mammals. The Triassic Period is known as the "Age Of Reptiles". I thought it would be an interesting time period to learn more about, and that's why I chose it for my research project. You can learn more about the Triassic by clicking [|here], or [|here].

**In****troduction** The Triassic Period happened during a significant part of Earth’s history. It was between the Permian period and the Jurassic period. During the Permian, Pangaea formed for the first time. There were new insects, a lot of reptiles, and seed plants. It ended with one of Earth’s major mass extinctions, wiping out 95% of all life. After the Permian and the Triassic Periods came the Jurassic. During this time, Pangaea was breaking apart, with the continents all near the equator. Earth was warm and humid, and there were high sea levels. The volcanoes became very active in this period. The dinosaurs thrived, and there were many giant herbivores appearing.These were very important parts of Earth's history, but the Triassic was a significant transition. This 42 million year long period nicknamed the "Age of the Reptiles", introduced the first mammals, turtles crocodiles, and of course, the first dinosaurs. These were all major changes in history, and they all relied on Earth’s abiotic life. ** Abiotic Life ** Even one change in the Triassic Period’s abiotic life had a huge impact on everything else. An   example of a change was Pangaea, the Triassic’s supercontinent. It was all of Earth’s land combined in one big continent. Pangaea stretched all the way from the North Pole to the South Pole. It affected everything in the Triassic Period, including the climate. Because all of the land was combined, almost none of it was near water. This made the climate of most of the land very hot and dry. The hot climate melted a lot of earth’s glaciers so there was almost no ice at all at the poles. This caused the sea levels to rise, which greatly influenced biotic life in the sea. In the mid- Triassic, Pangaea broke apart due to valleys that formed along fault lines. This resulted in two separate supercontinents; Gondwana in the south and Laurasia in the north. During this time, Massachusetts and the rest of North America were in the north as part of Laurasia. The ocean separating Gondwana and Laurasia was called the Tethys Ocean. This ocean helped to create mountains along the western coast of what today are the Americas. These mountains changed the climate of the Triassic, creating seasonal temperature variations that lasted throughout the rest of the period. The Triassic ended with one final abiotic event. A mass extinction wiped out a lot of life on Earth, leaving dinosaurs to dominate in the Jurassic. The abiotic life in the Triassic Period had a lot of influence, especially from Pangaea. We can tell a lot about this abiotic life from evidence such as fossils, landforms, and rocks.

**Abiotic Evidence** We can say that Earth used to be hot, that there was only one continent, that dinosaurs used to roam the land, but where’s the proof? Well, it’s in the rocks. That’s how we know that the Tethys Ocean created mountains during the Triassic. We can figure out how old rocks are by how many layers deep they are, and Triassic rocks are found all over North America. They are in many mountains, like the Sierra Nevada, Appalachian, Rocky, and Cascade mountains. They have also been found in Mexico, Texas, Canada, and some east coast states. Animals that became extinct millions of years ago can still be discovered today. How? B y the fossils they left behind. For example, a mollusk fossil from the Triassic was found in California in 2004. A relative of a cycad plant was found fossilized in Connecticut in 2005. Finally, the Earth’s first carnivorous dinosaur, //Coelophysis,// was fossilized in today’s New Mexico and found in 2003. These fossils have taught us a lot about life on Earth back in the Triassic.

**Biotic Life**

Of all prehistoric life, one animal stands out. The dinosaurs, born in the Triassic Period, are some of the most interesting parts of Earth’s history. The first dinosaur was //Coelophysis,// a small carnivore that hunted in packs. The //Plateosaurus// was another of the first dinosaurs, this time an herbivore. The Triassic produced the first mammals, which back then were much smaller. The most common animals in this period were fish, reptiles, and insects. Large reptiles like ichthyosaurs and plesiosaurs dominated the sea. Mollusks and brachiopods were the main invertebrates of the ocean. The Triassic’s amphibians were mostly frogs, salamanders, crocodiles, turtles, and snakes. The first flying reptile, called the pterosaur appeared in the Triassic.

The Triassic was when cycads and conifers first appeared. Plant life also included seed ferns, club mosses, dicynodonts, and ginkgos. Triassic plants were short and had thick, waxy coverings to help them stay moist. This made it necessary for animals to adapt larger teeth so they could bite the plants. The biotic life in the Triassic Period was mostly new life, or survivors of the Permian mass extinction. Unfortunately, a lot of this life would soon die out at the end of the Triassic in another mass extinction.

**Reflection**

I learned a lot about the Triassic Period during this project. It taught me not only about life 248 million years ago, but also about the other time periods around then. I learned about Pangaea and how it started breaking apart during the Triassic, I learned how the first mammals evolved from Permian reptiles, and I learned that there was a lot of sea life in the Triassic, thanks to the melting glaciers and rising sea levels. I liked how we each got one time period to study, so later we could teach the rest of the class what we learned. The difficult parts about this project were organizing all the information I got and and citing all my sources in the bibliography. **Bibliography:**
 * "Triassic." Animal Sciences. Ed. Allan B. Cobb. New York: Macmillan Reference USA, 2010. Gale Science In Context. Web. 28 Nov. 2011.
 * Beals, Kevin. Life through Time: Evolutionary Activities for Grades 5-8. Berkeley: Great Explorations in Math and Science, Lawrence Hall of Science, University of California at Berkeley, 2003. Print.
 * Exline, Joseph D. Earth Science. Needham, MA: Prentice Hall, 2001. Print.
 * Parker, Steve, and Jane Parker. Collecting Fossils: Hold Prehistory in the Palm of Your Hand. New York: Sterling Pub., 1997. Print.
 * Dixon, Dougal. Prehistoric World. Hauppauge, NY: Barron's, 2006. Print.
 * Coleman, Graham, and Tony Gibbons. Looking At-- Coelophysis: a Dinosaur from the Triassic Period. Milwaukee: G. Stevens Pub., 1994. Print.
 * Dutch, Steven I. "Triassic Period." World Book Advanced. World Book, 2011. Web. 5 Dec. 2011.
 * "Triassic Period." National Geographic. Web. .
 * Photograph. Creative Commons. http://search.creativecommons.org/