Ordovician Sea Environment

The Jurassic Period is a time period were new dinosaurs were being discovered and found. It was about 199.6 to 145.5 million years ago. Some of the species that were found in the Jurassic Period are the Stegosaurus, Ceratosaurus, Brachiosaurus, and Allosaurus. Each dinosaur had their own characteristics for survival.

Before the age of exploration and the pre modern era, the Americas were not connected to the rest of the world leaving them to develop on their own socially and economically. Africa also developed relatively alone except for costal contact with Muslim or Chinese traders. Western Europe, mainly isolated during the post classical age, developed alone except for some contact with Muslim merchants in Spain and Byzantine scholars fleeing ottoman Turks. This three ares

America came from every continent which is symbolized by the seven points on her crown that represent each continent.

This time era was known as the Paleozoic, and the main lifeforms were Synapsids and Sauropsids. The Synapsids were mammalian-like, and the Sauropsids were reptilian. “Synapsids had skulls with a single temporal opening and are thought to be the lineage that eventually led to mammals. Sauropsids had two skull openings and were the ancestors of the reptiles, including dinosaurs and birds” (Bagley). Toward the end of the era, the Synapsids began to dwindle in numbers. The end of the Paleozoic Era was the biggest mass extinction in the history of our planet, the Permian Extinction. Many get this confused with the K-T Extinction. The Permian Extinction was not what killed the dinosaurs because dinosaurs did not even exist yet. The Permian Extinction was quick, from the perspective of a geological standpoint, lasting only around 100,000 years. In that 100,000 years, 95 percent of marine life and 70 percent of terrestrial life died off

3c) (De Vleeschoucer, et al., 2014). These simulations suggest that it was possible for mountain glaciers to form on Gondwana in locations of both high altitude and latitude. An average monthly temperature of 37 °C is recorded at tropical Gondwanan latitudes and the highest land temperatures appear in January (Fig 4b)(De Vleeschoucer et al., 2014). Compared to modern pre-industrial simulations, Late Devonian sea surface temperatures are significantly higher. At 60° S this difference is 13 °C and 1.2 °C at the equator (Fig. 4a). Therefore, the Late Devonian climate has a low pole-to-equator temperature gradient and is comparable to post-industrial greenhouse climates (De Vleeschouwer et al.,

They also did not take out the other species of cephalopods, but they lived along side them evolving as well. Lastly, the Coleidea were the more successful of those two species, because they abandoned their shell and had more maneuverability of its species.

Approximately 65.5 million years ago most of the planet’s land animals and many of the animals in the seas went extinct. As far as we know this was caused by a massive asteroid colliding with earth in what is now the Chicxulub crater in the Yucatan peninsula. The collision is thought to have caused tsunamis and clouds of hot dust were sent into the atmosphere and probably started huge wild fires. Many of the animals that survived all of that would later die when the sun was blocked out for months or possibly years causing temperatures to drop and plants to die.

The jurassic period was the second period of the mesozoic era and happened between 199 and 145 million years ago. The jurassic period is when the gigantic continent ( pangea ) split apart and into the other continents. This period is when the herbivores (plant eaters) came to existence. oceans full of fish, squid, and

The earliest of the Big Five, the end-Ordovician or Ordovician-Silurian extinction events some 444 million years ago, are reckoned by many to be the second largest.

Are we on the brink of a sixth mass extinction? Many say yes, but there is also hard evidence saying no. Nonetheless, scientists can prove five mass extinctions in history. The first mass extinction happened roughly around 445 million years ago. It was named the Ordovician Extinction. The species affected were known as Graptolite, which are different types of sea creatures. Their demise on Earth lasted around only one million years. Around sixty to seventy percent of the species disappeared, and now the remaining species have evolved into something new. The extinction was likely because of a short and dangerous ice age, or the formation of the Appalachian mountains. It was likely that glaciers formed over the oceans and caused the sea levels to rapidly drop, killing the species.

The formation of Earth, 4.5 billion years ago till the evolution of hard-shelled animals, about 500 million years ago, is called the Precambrian period. There are many events during this time that are specific and affect the Precambrian life. The earth was formed and the first tectonic plate arose and began to move which caused many variations on the earth conditions during Precambrian that affected atmospheric composition and oceans. The level of oxygen arose in the atmosphere which enabled the enrichment of atmosphere with oxygen reaching its peak about 600 million years ago which enabled the first appearance of animal life that required oxygen for the production of collagen and the formation of skeleton. Also, during this period the ozone

The beginning of the Cambrian Explosion is normally thought to have occurred about 542 million years ago, during the Cambrian Period at the start of the Palaeozoic Era. This ‘explosion’ happened over millions of years although it is described as rapid in geological terms. In this period of time, the Earth saw the rapid appearance of a wide variety of animals. Ecosystems became much more complex in the Cambrian Period to those that were seen in Ediacaran Period. As the variety and number of new organisms increased, they started to occupy new marine habitats and environments. Cambrian seas saw many animals of different shapes and sizes; some lived on the sea floor while others swam in the water.

When creating the land, they fought over who had more land. In the making of the seven continents, Liam created two, Elijah created four, and Ava made one. Liam created North America and South America. Elijah created Europe, Asia, Africa, and Australia. Ava created Antarctica.

There is significant evidence from studies based on climate archives that the Earth’s climate about 10 000 years ago was very different from the present climate; it has changed a lot since the last glacial period which ended about 10 000- 12 000 years ago (Chappell, 1998). Hence, about 10 000 years ago the Earth was buried under ice sheets and it was much cooler than present temperatures (see Figure 1, Appendix) (Chappell, 1998). The Earth that has been cycling between cold and warm climates for ages and is currently in the interglacial period where it has slowly become warmer along with a rise in sea level (Watts, 2009).

Jurassic is a period of time with Dinosaurs, rodents and birds. There were also island seas consisting of sharks, sea monsters and blood-red planktons. The existing plants in that period were cycads, ferns and conifers. The Mesozoic era was about 245 million years ago to 65 years ago, so it almost lasted about 180 years in total. The Mesozoic era is divided into three periods of Triassic, Jurassic and Cretaceous. Mesozoic era means middle animals and it is the era, which the word’s fauna has changed from what is in the Paleozoic era and the most famous organisms of this era are dinosaurs. In the Mesozoic era, the extinction of more than 90 percent of species in the earth was observed and the reason behind it was mostly volcanic eruptions and climate changes. On the other hand, this era had massive changes that represented ecological niches and rise to new creatures such as rodent-size mammals and first dinosaurs. In Triassic, which was the first period of Mesozoic, the mammals and first dinosaurs existed. Later than that, the second period was Jurassic, which giant shaped dinosaurs and other kinds of dinosaurs were developed. Besides that the first flowering plants and primitive birds, with long teeth appeared in that era as well.