Free Essay

Dinosaurs of the Jurassic Period


Submitted By alisa060810
Words 1111
Pages 5
Dinosaurs of the Jurassic Period

Jurassic Period- 206-144 mya
• Took place roughly 210 million years ago.
• Lasted around 70 million years
• This was the second(middle) period of the three divisions of the Mesozoic era.
• Age of the Dinosaurs, first bird life.
Bower proclaimed that the "Triassic period began about 20 million years ago, and the Jurassic period began 210 million years ago"(1986).
During the Mesozoic, or "Middle Life" Era, life diversified rapidly and giant reptiles, dinosaurs and other monstrous beasts roamed the Earth. The period, which spans from about 252 million years ago to about 66 million years ago, was also known as the age of reptiles (Ghose 2013).
There is little supporting evidence that plant life is truly from the early Jurassic time frame, however, Brannan's research suggests "At the beginning of the Jurassic period the Earth saw the disappearance of seed-fern floras but the gymnosperms and true ferns were thriving"(Brannan 2012).

Early Jurassic- The Liassic Epoch (176 to 200 mya)
• Brought much warmer/wetter rainforest climate
• Marine reptiles evolved such as, Ichthyosaurus, Temnodontosaurus, Euycleidus.
• Terrestrial animals made an appearance such as the Stegosaurs, Tetanurae, Berberosaurus, Heterdonosaurids.
In the Early Jurassic, the Colorado Plateau region again became arid and the eolian sandstones record zonal as well as monsoonal circulation (Parrish 1993).
Following the dramatic decline, ichthyosaur diversity increased again to reach pre-extinction levels in the Early Jurassic, after which the group dwindled in diversity through the Middle and Late Jurassic and much of the Cretaceous until it disappeared at the end of the Cenomanian, 100 Ma, after 150 Myr of significant ecological dominance(Thorne, Ruta, Benton 2011).
Berberosaurus is the oldest known abelisauroid, and it represents a considerable temporal range extension for a lineage whose other members are Neocomian (Sereno et al., 2004) or younger (Tykoski and Rowe, 2004), except if the material from Tendaguru, recently described by Rauhut (2005), is proved by a future phylogenetic analysis to be an abelisauroid. Its presence implies a previously unrecognized diversification of ceratosauroids by the Early Jurassic (2005), is proved by a future phylogenetic analysis to be an abelisauroid. Its presence implies a previously unrecognized diversification of ceratosauroids by the Early Jurassic(Allian, Tykoski, Aquesbi, Jalil, Monbaron, Russell, Taquet 2007).

Middle Jurassic- The Dogger Epoch (176-161 mya)
• Flying small carnivores such as Peterosaurs, and Spenosuchid
• Beginning of the separation of Pangaea into Laurasia and Gondwana with the formation of the Atlantic Ocean.
• New terrestrial life such as Sauropods, Hypsilophodant, and the Brachiosaurs.
A new pterosaur (Mesozoic flying reptile) from the Middle Jurassic of China, Darwinopterus modularis gen. et sp. nov., pro- vides the first insights into a prominent, but poorly understood transition between basal, predominantly long- tailed pterosaurs and the more derived, exclusively short-tailed pterodactyloids(Lu, Unwin, Jin, Liu, Ji 2010).
The separation of Pangaea "happened around 200 million years ago, the supercontinent began to break up, forming the two continents Gondwana and Laurasia"(Ghose 2013).
Due to the breakup of Pangea, "About 180 million years ago the central Atlantic Ocean opened up between North America and northwestern Africa"(Briney).
Sauropods "dominated ecosystems for more than 100 million years from the Middle Jurassic to the end of the Cretaceous, setting a record that mammalian herbivores will only match if they can double their current geological survival time"(Sander, Clauss 2008).

Late Jurassic- The Malm Epoch (161-146 mya)
• Giant Sauropods (Mamenchisaurus, Stegosaurus) lived.
• Certain species died out. (giant Sauropods)
• How did the Jurassic period end? Minor mass extinction of Diplodocus and Branchiosaurus.
The size and body mass of the Sauropods "suggest that the unique gigan tism of sauropods was made possible by a combination of phylogenetic heritage (lack of mastication, egg-laying) and a cascade of evolutionary innovations (high growth rate, avian-style respiratory system, and a flexible metabolic rate)(Sander, Clauss 2008).
Vegetation and climate reconstructions indicate that the late Jurassic lacked a tropical ever wet biome, which is associated in today's world with high biodiversity(Rees, Noto, Parrish, Parrish 2004).
Selenium may have been the main cause for the extinction of dinosaurs and other animal species at the end of the Mesozoic Era(Koch 1967).
It is proposed that dinosaurs and other animal species that relied upon abundant vegetation for food were poisoned by selenium(Koch 1967).
It's widely believed that the dinosaurs were wiped out by a cataclysmic event such as the crash of a giant meteor that was hurled to Earth(Koch 1967).
Ward speculates that the same kind of thing may have happened in the mass extinction 200 million years ago, paving the way for dinosaurs. "This is the first time ever that we can see how sudden this event was," said Peter Ward, a University of Washington paleontologist who led the team that reported the new research in the May 11 issue of Science. "It was very quick, not a long, protracted episode."(Parsell 2001).

Works Cited
Allian, Ronan, Ronald Tykoski, Najat Aquesbi, Nour-Eddine Jalil, and Michael Mondaron. "An Abelisauroid (Dinosauria: Theropoda) from the Early Jurassic of the High Atlas Mountains,." Journal of Vertebrate Paleontology, 27.3 (2007): 610-24
Benton, MJ & DAT Harper (1997), Basic Palaeontology. Longman, 342 pp.Cornet, B & NG McDonald (1995), A new cheirolepidiaceous conifer from the Lower Jurassic of North America.
Bower, B. "Nova Scotia Fossils Illuminate 200-Million-Year-Old-Changes." Science News 129.6 (1986): 86.
Brannan, Amy. Jurassic Period Plants. Jurassic Times, 16 Jan. 2012. Web. 17 Sept. 2014. .
Briney, Amanda. "Pangaea." All About the Supercontinent Pangaea. About education, 2014. Web. 17 Sept. 2014. .
Ghose, Tia. Mesozoic Era: The Age of Reptiles. Live Science, 1 Aug. 2013. Web. 17 Sept. 2014. .
Koch, Neil C. "Disappearence of the Dinosaurs." Journal of Palentology 41.4 (1967): 970-72
Lu, Junchang, David M. Unwin, Xingsheng Jin, Yongqing Liu, and Qiang Ji. "Evidence for Modular Evolution in a Long-Tailed Pterosaur with a Pterodactyloid Skull." Proceedings: Biological Sciences 277.1680 (2010): 383-89.
Parrish, Judith T. "Climate of the Supercontinent Pangea." The Journal of Geology 101.2 (1993): 215-33
Parsell, D L. Mass Extinction That Led to Age of Dinosaurs Was Swift, Study Shows. National Geographic News, 10 May 2001. Web. 19 Sept. 2014. .
Rees, P.McAllister, Christopher R. Noto, J.Michael Parrish, and Judith T. Parrish. "Late Jurassic Climates, Vegetation, and Dinosaur Distributions." The Journal of Geology, 112.6 (2004): 643-53
Sander, Martin, and Marcus Clauss. "Sauropod Gigantism." Science 322.5899: 200-01
Thorne, Philippa M., Marcello Ruta, and Michael J. Benton. "Resetting the evolution of marine reptiles at the Triassic-Jurassic boundary." Proceedings of the National Academy of Sciences of the United States of America, 108.20 (2011): 8339-44

Similar Documents

Premium Essay

Dinosaurs Persuasive Essay

...Since the first dinosaur bone was unearthed and mounted in a museum for the world to view, people have been fascinated by the gigantic ancient beasts that once ruled the world. Soon movies brought the dry dinosaur bones to life, featuring dinosaurs as the biggest villains of the film industry. America’s love affair with lost worlds, super-sized villains, and industry leading special effects, helped to make dinosaurs on the big screens biggest stars. Dinosaur movies have captivated our imagination, haunted our dreams and entertained Americans since the early days of film. Prehistoric Cinema: Old Bones Live on the Silver Screen The early mass discoveries of dinosaur bones in Colorado and Wyoming lead the to the Great Dinosaur Rush, where...

Words: 1479 - Pages: 6

Premium Essay

Time Traveling

...would travel back in time to the time period of 1920s-1980s in the United States of America. Another reason why I would travel back in time would be in the time period of 1776-1820s in the United States of America. Then my final destination would be the Jurassic Age to see the dinosaurs. As you were reading/hearing what I said I hope that you assume that I like U.S.A. history and how dinosaurs were like. I would see a pleather of things in the time period on 1920s-1980s. For instance, I would get tutored by Albert Einstein himself. Also I will also purchase ten pairs of Back to the Future shoes, and then sell them in the present for profit. I will also see what Northern Cambria (Spangler/Barnesboro) was like. Throughout these years that I would travel, I would get myself different types of suits and get a mint-conditioned Johnny Cash Album –the rare one. The next time period would be from 1776 to the 1820s to see what old America was like. For instance, I would look for George Washington to see what he looked like and to hear how he spoke. Next I would see the Declaration of Independence being made and actually be part of their conference for the Declaration of Independence. Also, since I am a coin collector, I would take hundreds of the first coins that were made in the U.S.A. I will also, from a distance with binoculars, watch how the War of 1812 unraveled and took form. Most likely, the final destination for now…, would be the Jurassic Age. During this age I will have to...

Words: 498 - Pages: 2

Premium Essay

Dinosaurs in Alaska

...Dinosaurs In Alaska? When you hear a place about Alaska, we think of snow, polar bears, glaciers, and cold weather. When you think of dinosaurs, we think of tropical places and hot climates. You would probably doubt dinosaurs could have ever lived here in Alaska. But about 65 million years ago they not only lived here, they thrived! There are a lot of information about dinosaurs, but what this paper will cover is how dinosaurs directly relate to Alaska. After reading this paper, you will find out how dinosaur research started and how long ago dinosaurs lived in Alaska. Plus find out the type of dinosaurs that lived Alaska, and the type of climate and which parts of Alaska that they lived in. You will also find out what type of evidence they found, if dinosaurs are related to the oil industry, who is still studying dinosaurs, and how this topic is introduced to the public. How it all began Dinosaurs strolled the earth over 245 million years ago. So it would only be fair to go all the way back to the beginning and quickly summarize how it all happened. Earth’s history is categorized into two eras, and then categorized by periods. The two eras are Paleozoic era, and Mesozoic era. Paleozoic era - (560 to 276 million years ago): This is the period where the first fish, corals, shellfish, insects, spiders, and swamp forests appeared. Mesozoic era - (350 to 65 million years ago)We are most interested in this era. This era contained 3 periods: Triassic period, Jurassic...

Words: 3781 - Pages: 16

Free Essay


...GEOLOGIC TIME Go to to fill in the following table: ERA | PERIOD | INDEX FOSSILS USED TO IDENTIFY ROCKS OF THIS AGE (DESCRIBE WHAT THESE FOSSILS ARE AS WELL) | ABSOLUTE AGE RANGE (MYA) | MAJOR GEOLOGIC EVENTS | CENOZOIC | Quaternary | Evidence of Homo Sapiens Sapiens and early types of plants.Pleistocene conifers, mosses, flowering plants, insects, mollusks, birds, mammals (sloths, bison, sabre-toothed cats, mammoths, early human hunters). Diatoms, foraminifera, and plant pollen. | 1.8 MYA to today. | Yet the Holocene has witnessed all of humanity's recorded history and the rise and fall of all its civilizations. It was during the Pleistocene that the most recent episodes of global cooling, or ice ages, took place. Temperate zones were alternately covered by glaciers during cool periods. The Pleistocene also saw the evolution and expansion of our own species, Homo sapiens. | | Tertiary | Grazing mammals, such as members of the perissodactyl and artiodactyls diversified in the Miocene and Pliocene.Long legged grazers.Chalicotherium , perissodactyls. artiodactylsHyaenodon horridus, elephants, horses, various grassesUngulates such as Artiodactyla and Perissodactyla, Vivveravus | 65 to 1.8 MYA. | The cooling and drying of the global environment may have contributed to the enormous spread of grasslands in this time. The change in vegetation undoubtedly was a major factor in the rise of long-legged grazers who came to live...

Words: 895 - Pages: 4

Premium Essay

Reptile Research Paper

...The history of reptiles began when the first reptiles evolved from amphibians. Fossils of the first reptiles have been found in deposits from the early Carboniferous period (359-299 mya) and possessed characteristics that made them greatly resemble lizards; they were small in size, had four legs, were vertebrates, and possessed teeth that classified them as insectivores. These reptiles flourished due to the sheer amount of insects available around them, and by the end of the Permian period (299-251 mya) they had become the dominant land vertebrates. The Permian Period ended with the formation of Pangaea. Reptiles were successful in the interior of Pangaea because of the arid climate that they were adapted to; however, the end of the Permian...

Words: 1597 - Pages: 7

Premium Essay

Triassic Plots: The Evolution Of Dinosaurs

...million years ago, dinosaurs began to evolve after the period the Permian extinction. dinosaurs began to develop and grow throughout the Triassic period, and were seen as a great threat to other living creatures around them. However, about 66 million years ago, dinosaurs became extinct near the end of the Cretaceous period due to a huge comet or asteroid that struck the face of the earth. This area, at the time, was under water but is today known as modern day Mexico. Dinosaurs had first began to evolve from a species known as the archosaurs. Archosaurs were Triassic reptiles and were much smaller than the later species of dinosaurs. These Triassic reptiles carried certain features that were much different from the species that they had evolved into. They had a much different posture, almost as if they were “locked in”...

Words: 724 - Pages: 3

Premium Essay

The Final Period Of The Dinosaurs

...Boom, thod, rawr! Wow, a dinosaur! Well, that what I would have said if I heard those noises. Dinosaurs were the first living organism to walk the earth. Their dynasty lasted for 200 million years and was separated into three different periods: the Triassic, Jurassic, and Cretaceous. The Cretaceous period was the final period of the dinosaurs and to have a better understanding of this period we must look at the climate and the geographical landscape, then we must have knowledge on the many things that lived during this time (dinosaurs and unique sea animals), and finally how the Cretaceous came to an end. The Cretaceous was made up of tropical and subtropical climate throughout the globe. These two types of climates controlled the Earth causing it to have hottest temperatures during the...

Words: 543 - Pages: 3

Free Essay

The Allosaurus Dinosaur

...Name: Tutor: Course: Date: The Allosaurus dinosaur The Allosaurus dinosaur is a member of the dinosaur group called the Theropods.The Theropods were meat eating dinosaurs that walked on their two back legs. The name Allosaurus means ‘different lizard’. The Allosaurus is believed to have lived about 163 to 144 million years ago (Britannica 86).This period is referred to as the late Jurassic period. It had a life span of 25 years. Most of the fossils of the Allosaurus where found in North America, Colorado, Utah, New Mexico, Montana, south Dacota and Wyoming (Britannica 86). The Allosaurus reached up to 39 feet (12 meters) in length, stood about 15 feet (4.5 meters) tall, and weighed up to 2 tones. It had a massive head that measured about 3 feet (1 meter) long with it being supported by a short thick neck together with two horns sticking out of its head. It possessed sharp teeth that were curved and had saw like edges. The Allosaurus had sharp claws on the three toes of each hind foot and long grasping claws on the three toes of each front foot. To cap it all it had along, strong and heavy tail that was mainly used to maintain balance. The Allosaurus is believed to be a meat-eating dinosaur that preyed on the plant eating dinosaurs. Its sharp teeth made it fit for meat eating. Its main pray is believed to be the Stegosaurus dinosaur. The Allosaurus hunted in cooperative packs according to some scientists. By hunting in packs they would bring down very large pray. Although...

Words: 584 - Pages: 3

Free Essay

Terrible Claw

...tiles of the floor. Visibly frightened, Lex and Tim tremble as one of the beasts peers its head over the island they cowered behind. Luckily for them, it senses nothing and clicks onward. Then, as if by accident, the raptors massive, muscular tail sweeps across the countertop and sends pots and pans crashing on top of the kids. Lex shrieks as they both dart behind yet another row of counters, but it seems that the raptors take no notice over the crashes and clangs of the pans. It seems they have evaded their predators until Tim flattens himself to the side of cupboard accidentally knocking over a ladle, which seems to stop time on its way to the hard, thunderous ground. Immediately as the utensil makes its deafening ring, both dinosaurs are on the attack: one leaps upon a table as the other makes its way around to the sound of the noise. Lex beckons Tim to follow her to the opposite side, but Tim is frozen in fright. He instantly regrets his decision, though, as one Velociraptor roars as it comes upon the ladle. After their brief inspection of the spoon, they are about to round the corner that would reveal Tim, but Lex manages to catch their attention by banging a ladle of her own against the floor. Now, the...

Words: 2632 - Pages: 11

Premium Essay

Comparison Between T. Rex And Dinosaurs

...T. Rex had a well-developed sense of smell, and its hearing and vision were probably better than average by late Cretaceous standards. One unconventional weapon may have been T. Rex's bad breath; rotting chunks of meat stuck in this teeth could have transmitted fatal bacterial infections to any animal lucky enough to survive an initial bite.As "arms races" go, T. Rex was a hands-down loser this dinosaur's arms were so short and stubby that they would have been nearly useless in a fight. Also, despite what you've seen in movies like Jurassic Park, T. Rex probably wasn't the swiftest dinosaur on the face of the earth; an adult running at full speed might not have been a match for a five-year-old kindergartner on training wheels. And now for...

Words: 258 - Pages: 2

Free Essay


...Dinosaurs, contrary to what many people think, are not just big lizards. While it is true that the name dinosaur (coined by Sir Richard Owen in 1842) means "terrible lizard" in Greek, dinosaurs are quite a distinct group from lizards. The first dinosaur bones were discovered in 1822 in Sussex, England, by Gideon Mantell. It was a herbivore (plant eating) dinosaur later given the name Iguanodon. Shortly after the Sussex discovery the first carnivorous dinosaur, a Megalosaurus, was found. It is believed that from about 230 million years ago, to 65 million years ago (The Mesozoic Era) dinosaurs were the dominant form of life on Earth. At the end of the Mesozoic, dinosaurs, and many other species of life, went extinct. The cause of this extinction is a mystery. Dinosaurs are considered to be reptiles. Unlike most reptiles dinosaurs all walked with their legs directly below their hips. This is different than a lizard or a crocodile where the top section of the limb is splayed out horizontally from the body and the lower section goes from the "knee" joint straight down to the ground. Because of this lizards and crocodiles move low to the ground and almost appear to be dragging themselves around on their bellies. In contrast, dinosaurs walked in an upright manner (Though a few species, like Triceratops, did retain the lizard-like sprawl on it's front legs as it lumbered about). We can tell dinosaurs walked with their feet under their hips by carefully examining the way their...

Words: 816 - Pages: 4

Free Essay

Historical Geography

...The Cambrian Period is in the Paleozoic Era. The Paleozoic Era was known as the "Age of Marine Life." This "Age of Marine Life" all began with what is called the "Cambrian Explosion." The "Cambrian Explosion" happened roughly 542 million years ago and obviously took place during the Cambrian Period. It was when most of the major groups of marine animals appeared in a relatively short period of time. According to fossil records, Bryozoa, algae, sponge (porfera), Arthropoda (trilobita), Mollusks (plecypoda, gastropoda, cephalopoda), and corals first appeared all in the Cambrian Period.   The Ordovician Period followed the Cambrian Period, and this is when some of the first brachiopods appeared, such as clams, snails, and cephalopods. Also, ostracoderms, jawless armored fish, were the earliest vertebrates that appeared in this time period. "Typical Ordovician fish had large bony shields on the head, small, rod-shaped or platelike scales covering the tail, and a slitlike mouth at the anterior end of the animal" (   During the Silurian, there was a widespread radiation of crinoids, a continued proliferation and expansion of the brachiopods, and the oldest known fossils of coral reefs. There was also the appearances the first known freshwater fish. And finally, the first record of life on land! Fossil records show a group of fungi on land, and also arachnids and centipedes. According to, "Most Silurian plant fossils have...

Words: 917 - Pages: 4

Premium Essay


...In the following I will discuss the atmosphere of the late Cretaceous (end of the dinosaur era) and how it may have contributed to the extinction events that occurred at the end of this era. I will also discuss how scientists determine the composition of ancient atmospheres. The Cretaceous period was from 145 to 65.5 million years ago. You had the early cretaceous epoch and the late cretaceous epoch. Mass extinction happened and comprised of 80-90% of marine species and 85% of land species, including the dinosaurs. About half of all life-forms died out, including the dinosaurs, pterosaurs, plesiosaurs, ammonites, and many families of fish, snails, sponges, sea urchins (Benton, 2003). The meteor impact inhibited photosynthesis. The atmosphere was filled with dust cloud which blocked the sunlight for at least a year. Sulfuric acid was injected into the stratosphere. This also created a reduction in sunlight to the Earth by 20%. Because the atmosphere was filled with this acid and dust clouds the plant life and small creatures would die off. It takes at least 10 years for the atmosphere to clear itself of these pollutants. An impact such as this can also produce acid rain. There are many animals that can not handle acid rain. Therefore, this would also play a part in extinction of species. ( When it comes to how scientists determine the composition of ancient atmospheres, I found the following; “Ages of ice samples found on the Earth cover a span approaching...

Words: 435 - Pages: 2

Free Essay

Evidence of False Thumb

...organisms as all there is. We know dinosaurs once lived and are now extinct. An article explored the routes of diversification taken by early mammals, only those lineages in the far right based on figure 1, in Cenozoic Era have survived to the modern day. Each era group showed how common it was in various time period. The multituberculates were very common until the early Paleocene. In history, they were the dominant group of mammals, existing in the largest numbers for the longest time and are now extinct. Their generations, the spalacotheriods and eutriconodonts, were successful in the Early Creataceous but its population declined by the end of that Period. At the root of the tree showed (figure 1) the groups of mammaliaforms, not true mammals, but have some similarities. This group first appeared in the Jurassic era and didn’t survive the Cretaceous era. The Cretaceous ended with a global extinction that wiped out the non-avian dinosaurs, and several stem-mammals suffered the same fate. Others lingered into the Paleocene Epoch only to become extinct, possibly outcompeted in the rapid radiation of the therians. We tend to think of extinct groups as more “primitive” than extant groups, but the mammals radiated rapidly and many niches occupied today were occupied by now-extinct forms in the past. In the phylogentic tree some show niches available and how they have been filled at various times. The presence of a gliding mammaliaform in the Jurassic is especially interesting A few...

Words: 1589 - Pages: 7

Premium Essay

Thematic Essay On Climate Change

...Anthropomorphic Climate Change is highly exaggerated, and the effects that we have on weather patterns, is negligible. The carbon-dioxide concentration in Earth's atmosphere, has a concentration of 400 parts-per-million. Carbon Dioxide, in minute numbers, cannot trap much heat at all. Climate change does occur, but naturalistically, and over the course of thousands, if not millions, of years. 50,000 years ago, ice measuring around one mile high covered most of the Northern Hemisphere, before most of it had melted. Roughly 1,000 years ago, there was a major warming period, to where the climate was warm enough that there are records of vineyards growing in England. A few hundred years later, would be known as the Little Ice Age, as temperatures were cooler than they were today. I would also argue...

Words: 441 - Pages: 2