Presentation on theme: "Jurassic Period By: Sonia Kups Bio Project. Jurassic Period Jurassic period began 208 million years ago and ended 144 million years ago. The whole."— Presentation transcript:
Jurassic Period Jurassic period began 208 million years ago and ended 144 million years ago. The whole Jurassic period lasted 064.0 million years. The Jurassic period was part of the Mesozoic Era. The Jurassic period was divided into three parts: early Jurassic- Lias, middle Jurassic- Dogger and late Jurassic- Malm. The Jurassic period is the middle period of the Mesozoic era. The Jurassic is known as “The Age of Dinosaurs.” Most animals die out in the Triassic period, the dinosaurs survived The armored placodonts and great Shastosaurs were all extinct because of the mid-Carnian and Rhaetic extinctions from the Triassic period. This period was the height of the dinosaurs existence. The word “Jurassic” came from the Jura Mountains in Europe.
Geography In the beginning of the Jurassic Period most continents were joined together. The Atlantic Ocean started to form and the Americas separated from Africa. Arizona, Colorado and Utah were all deserts. Italy, Greece Turkey and Iran were attached to the North African part of Gondwanaland. Sandstone, limestone, shale and gypsum were deposited all over North America. The Sierra Nevada, Klamaths, Cascades, Coast Ranges, Rocky Mountains and coastal mountains of Canada and Alaska were formed. No glaciers were present. The continents began to rotate and separate from each other.
Geography There were three continents: North America, Eurasia and Gondwanaland New sea floor formed along the South Atlantic. The sea level rose in the Jurassic Period flooding large portions of continents. The Sundance Sea formed in North America. The land of the Jurassic period contained black organic mudstones with microcrystalline limestone. Same group of dinosaurs and plants lived on all the continents. Yorkshire, UK was actually a shallow sea or a lagoon during the Jurassic period. What is now the Amazon and Congo forests were deserts in the Jurassic period.
Climate Tropical climate About 15 degrees F warmer then current temperature The climate was warmer and moister then that of the Triassic period. As time went on the climate became more humid. Nowadays people classify the Jurassic terrestrial environments in different climate zones by looking at the leaf changes, geographic distribution and climate relationship. As researchers find the original climate of the Jurassic they will see which plants lived on what parts of land. In the early and middle Jurassic Pangea was very arid and hot.
Plants Gymnosperm plants were present. Cycads were the main dominant plant life. There were two different types of cycads: the palm like ones and the short ones that looked like brushes. Conifers, ginkoes, palms, horsetails and ferns were present. Forests contained ferns and ginkos. The ground was covered with ferns and cycads. On the ocean floor different types of plankton were abundant. There was no flowering plants. The caytoniale plants later evolved into flowering plants. The Petrified Forest National Park in Arizona has preserved trees from the Jurassic and Triassic periods. Plants were the basis of the food web.
Cycads This cycad was one of the palm like ones that bigger dinosaurs, like the brachiosaurus ate from. There were also separate female and male cycad plants.
Animal Biology 1000 species of insects were present. Some of these insects can be found on earth today The reptiles were the dominant animal. Dinosaurs ruled the land. Crocodiles, ichthyosaurs and plesiosaurs ruled the sea Pterosaurs ruled the sky The first bird-like reptile appeared in the Jurassic Period known as Archaeopteryx. Primitive mammals appear, but they are very small and not very important. Invertebrates were plentiful: sponges, corals, bryzoa, gastropods, bivalves, ammonoid, belemnite and cephalopods Clams, snails and branchiopods were also common On land millipedes, scorpions, spiders and mites were present. Modern shark groups appeared.
Animal Biology During the late Jurassic some small carnivores developed feathers and learned how to fly. The largest land animal was the sauropods. The sauropods were plant eating. The dinosaurs ruled land for 135 million years. Some of the herbivores during the Jurassic were prosauropods, cynodont synapsids and other mostly small ornithischian dinosaurs. Plant eating dinosaurs were the biggest dinosaurs around. Dinosaurs like the Stegosaurus had brains the size of a walnut and yet grew up to be about 30 feet long.
Sauropods These were the largest dinosaurs in the Jurassic period. They were herbivores. These dinosaurs were 46 feet long.
Early Jurassic Also known as Lias. The word Lias might of come from the local English spelling of the word layer. There were four parts in the Early Jurassic: Toarcian, Pliensbachian, Sinemurian and Hettangian. Lasted from 195 million years ago to 180 million years ago. Ammonoids diversify. The early Jurassic saw great disposition of limestone. Evolution of dinosaurs and other animals stops in this period.
Middle Jurassic The middle Jurassic was called Dogger. There were four parts in the middle Jurassic: Callovian,Bathonina,Bajocian and Aalenian. Lasted from 180-154 million years ago. Marine life like ammonities and bivalves dominated the earth. New dinosaurs evolved like cetiosaurs, brachiosaurs, megalosaurs, and hypsilophodonts. Ichthyosaurs reduce in diversity. Cetiosaurids flourish. Pangea starts to separate. The cooling process of the earth is starting to take place.
Late Jurassic Also known as Malm. The late Jurassic period had three parts: Tithonian,Kimmeridgian and Oxfordian. Lasted from 146-135 million years ago. Central Atlantic Ocean was a narrow ocean that separated Africa from eastern North America. Eastern Gondwana separates from western Gondwanaland. Dinosaurs Sauropods, Camarasaurs, Brachiosaurs and Diplodocids flourished. Smaller animals like reptiles, lizards, early mammals and early birds also were abundant. As a result of Pangea breaking up the climate changed The climate was less dry and snow and ice covered polar regions.
Fossils Jurassic deposits can be found in the Rocky Mountains, England, western Europe and other parts of the world. The Blue Nile Gorge in Ethiopia has some of the first dinosaur fossil. In 1905 the Saurian Expedition in the West Humboldt Range in Nevada found Jurassic fossils of ichthyosaurs. The Solnhofen Limestone in southern German has many detailed fossils from Jurassic deposits. Many Solnhofen Limestone fossils are of fragile or soft bodied organisms which usually leave broken fossils but not these. The Tendaguru Formation is filled with deposits from the Jurassic period. About 225,000 kg of bones were uncovered at the Tendaguru Formation over 2 and a half years. Lime stone and deposits are important in studying fossils because these stones contain the remains of ancient dinosaurs.
Interesting Facts The name Lias was taken by a geologist from an english quarryman’s pronunciation of the word "layers". The movie Jurassic Park by Steven Spielberg was actually somewhat inaccurate. The dinosaurs, like Triceratops and Tyrannosaurus rex, did not evolve until the Jurassic period was over. Most of the dinosaurs featured in the movie were from the Cretaceous period.