The Permian Period commenced 298.9 million years ago and ended 252.2 million years ago, ranging from the close of the Carboniferous Period and the beginning of Triassic Period. About 250 million years ago, at the end of the Permian period, something killed some 90 percent of the planet's species. The species of animals in the seas survived no more than 5 percent. On land less than a third of the large animal species made it; nearly all the trees died (Hillel J. Hoffman, 2015). Marine life was devastated, with a 57% reduction in the number of families (Sepkoski, 1986). Oceanic life suffered the most, but terrestrial life forms were also greatly affected. All major groups of oceanic organisms were affected with the crinozoans (98%), anthozoans (96%), brachiopods (80%) and bryozoans (79%) suffering the greatest extinction (McKinney, 1987). The world, today, is alive because of the remaining 10 percent. The events that took place were in phases and some of the causes were an asteroid hitting the earth, sea level fluctuations flood basalt eruptions, a drop in oxygen levels from the acid rain caused by volcanic ash, calamitous methane release, etc. …show more content…
Hartmann), called the K/T-Boundary hit the Permian Earth and made a huge explosion causing a crater roughly 110 miles across. The debris alone entered high atmosphere and blanketed the Earth in dust that blocked sunlight for numerous months or weeks (Carl Sagan, 1980). This asteroid disrupted the climate, and that led to a downward slope to the gradual extinction in more than 90 percent of the Earth’s species. Some scientists have different opinions to the actual causes of the mass extinction. Scientists go all over the world to test their theories; in China, the boundary clays are a result from the ejecta dust from a comet impact, or from the ash of a massive volcanic
In this paper Martin is arguing that late quaternary or near time extinctions where caused by human activity or as he calls it “overkill”. Martin recognizes that there have been many forces that have triggered extinctions in the planet on the past but disagrees with the idea that near time extinctions where caused by some commonly believed causes like climate change, disease or nutrient shortage. He argues that the arrival of humans to different continents, islands and the subsequent excessive hunting, the introduction of diseases and other competitors and predators was the cause of extinction of a great number of species “As our species spread to various continents we wiped out their large
Seaworld is a giant marine life theme park. The greatest attraction to these many theme park would be those killer whales. In fact, these killer whales are the face of the park. As gigant as these mammals are, seaworld is keeping them in some pretty tight quarters. Mr. Jett and Mr.Ventre says “Wild killer whales can swim a hundred miles daily as they socialize, forage, communicate, and breed. In stark contrast, with little horizontal or vertical space in their enclosures, captive orcas swim only limited distances, with most spending many hours surface resting.” The animals don't have the freedom they need. Also when taking the whales out of their natural habit the whales tend to be depressed and not as heath in that situation. They need their freedom in the big ocean blue. Bring them into the small living units, breeding whales in captivity all for the entertainment of humans. At young ages the calves are taken away from their mothers on to a new seaworld park. Mothers of the calves have even been seen denying their offspring.
The disaster theory, Gould claims, is an example of good science. It has testable evidence and has an impact on studies in other fields of science, it develops further and explains why the extinction of dinosaurs occurred simultaneously with other events. This theory suggests that a large comet hit the Earth sixty five million years ago, causing the cloud of dust to rise into the sky and to block sunlight. As a result, world temperatures went down significantly, the ice age bega...
Flatworms belong to the phylum Platyhelminthes. They have the simplest body plan of all bilaterally symmetrical animals. They are called flatworms because their bodies are compressed. The mouth is the only opening into the digestive cavity the flatworms have. Food is taken in through this hole and wastes are discharged also through this hole. Flatworms have a well-defined nervous, muscular, excretory, and reproductive system. The flatworm distributes the food it digests through a digestive tube that branches throughout all of its body parts. The fact that the worm’s body is flat serves many purposes. It allows the worm to hid in small spaces, to fit into the opening of other animals if the worm is parasitic, and it means that all the cells are close enough to the surface for exchange of oxygen and carbon dioxide with the environment (Meinkoth 399).
The eradication of species numbers average at a toll close to one hundred percent of earths total living creatures. “It is the Earth's most severe known extinction event, with up to 96% of all marine species and 70% of terrestrial vertebrate species becoming extinct” (Sahney, and Benton 759). Not only where marine and terrestrial species effected but this catastrophic event is the only recogni...
...iod. The glacier formation led to the enormous decrease of the sea level which dried out the swamps. Swamps form because of the water level was high and flooded the forest so the low sea level really affected the huge swamps areas of the Carboniferous period. The climate changed from hot and humid to cool. The plants couldn’t adapt to this change so most of the ones that flourished during the time period died off but it led to new plants forming. Most of the amphibians that were prosperous during this time also couldn’t adapt to the environmental climate change so most died off. The insects also couldn’t live through the change. The reptiles however made it through the climate change. They were able to adapt unlike all the other species they lived with during the carboniferous period. These environment changes eventually led to a new time period, the Permian Period.
Throughout Earth’s history there have been many changes. These changes have consisted of temperature fluctuations, atmospheric differentiations, extinctions of various plant and animal life, etc. Over time everything seems to have evolved in some way form or fashion. However, the Permian Era extinction was different from all the rest. This extinction affected every form of life, but especially the marine life. Researchers have stated that 93-97% of all Earths species went extinct during this period of time. This essay will explain how a once blossoming progressive era turned into Earths most catastrophic event.
The most significant event of the Cretaceous era came at its end. Nearly 65 million years ago, the second most severe mass extinction in earth’s history occurred. This resulted in the loss of around 80% of species living at the time. Though nowhere near as severe as the end-Permian mass extinction, the end-Cretaceous extinction is the most well known mass extinction event. This is due to the violent event that caused it the extinction, as well as the chapter of earth’s history that it closed: the Dinosaurs. The Cretaceous Event ( often shortened to K-T event) Of the animals that were killed off were the flying reptiles (pterosaurs) and the last few mosasaurs and plesiosaurs, both early marine reptiles. Many mollusks and species of microscopic plankton were killed. Terrestrial plants suffered mass extinction as well. Almost 60% of terrestrial plants were lost. This led to high extinction rates among insect populations, especially insects that were highly specialized to feed on just a few types of plants had it the worst. It took approximately 9 million years for the global insect populations to recover from the Cretaceous extinction. Immediately after the extinction, the earth saw an explosion of short term species who respond well to fire, or other external disturbance. Evidence of the catastrophe comes from a thin rock layer deposited worldwide just after the impact. It is dominated by fossil plants whose descendants recover quickly after fires of other disturbances, such as Fire Weed in Alaska. The causes of the Cretaceous extinction are still being debated by paleontologists. Scientists agree that the main cause of the extinction was a...
Among the species that perished were the dinosaurs, pterosaurs, belemnoids, many species of plants, except ferns and seed-producing plants, ammonoids, marine reptiles and rudist bivalves. Severely affected organisms included planktic foraminifera, calcareous nannnoplankton, diatoms, dinoflagellates, brachiopods, mollusca, echinoids and fish. Mammals, birds, turtles, crocodiles, lizards, snakes and amphibians fared much better and were mostly unaffected by the End-Cretaceous mass extinction (“The End-cretaceous (K-T) Extinction”, accessed 2000...
Earth has gone through five fully major extinctions before. We currently are in the process of Earth’s sixth mass extinction. This mass extinction is closely related in severity to the extinction of the dinosaurs. Earth’s extinctions are broken into three different areas. The first area was the large number of animals caught by hunter-gathers. The discovery of agriculture led to the second area of extinction, wildlife habitats. These wildlife habitats were destroyed due to humans starting to stay in one area.
middle of paper ... ... The Web. 13 Mar. 2014. The 'Standard' of the 'Standard'. Dinosaurs: Climate Change and Biodiversity."
The extinction of the Tyrannosaurus Rex was obviously due to the same reason. Every other living species was killed sixty five million years ago. Although it is believed that the asteroid theory is the cause of extinction of the Crustaceous Period, we cannot be positive. The environmental effects of this problem were that the dinosaurs living during this period perished from the earth and their extinction remains a mystery to us to this day. All we can do to reenact what happened is use the technology we have in the twenty first century to find more evidence to see what went wrong so long ago. By discovering things like what happened to the Tyrannosaurus Rex we can use this information to prevent an event such as a mass extinction from happening a second time.
Did you know that more than 90 percent of all organisms that have ever lived on Earth are extinct? According to Pandey, the author of Humans Pushing Marine Life toward ‘Major Extinction’, nearly 10,000 species go extinct each year, and this rate is estimated to be 1,000 times higher than the natural extinction rate (1). Human beings are causing irreversible damage to the oceans and their wildlife, which is being led by two major reasons: Commercial fishing or over-fishing, which damaged the marine environment and caused a loss in the marine life diversity, and pollution, which is a primary way of the extinction causes that drastically modifies the marine life habitat. As a result of the commercial fishing and pollution, many of the marine species will start disappearing of the oceans. Briggs emphasizes that over-fishing “has induced population collapses in many species. So instead of having less than a hundred species at risk, as was the case some 30-40 years ago, there are now a thousand or more (10).”
Because the CO2 levels are rising, the ice caps are melting and many more animals can become extinct. When pangea started splitting, there was a lot of volcanic activity, which cause the death of many dinosaurs. A meteor also hit earth and the mass extinction of many land and marine animals happened. There have been five mass extinctions in Earth’s history. The worst one wiped out ninety-six percent of marine life and seventy percent of land organisms. This took millions of years to recover.
The oceans need to be protected because it is where life began and if not taken care of, life as we know it will end. When dangerous substances go into the ocean, ecosystems are suffer and become endangered along with lives of people and of marine life. Surfrider Foundation recognizes the importance of protecting and preserving the quality and biodiversity of the world's coasts because they are truly irreplaceable. There is also historical evidence of ocean pollution being present in the past, but the problem still lingers today. Heal the Bay discovered that,“Did you know there is a DDT and PCB hot spot off the coast of Palos Verdes? This superfund site (which indicates it's one of the most polluted places in the United States), is left over from a 1930's era chemical plant. Because DDT takes so long to break down in the marine environment, it persists to this day, contaminating certain species of fish. There are also highly polluted sediments in the Long Beach area, a sign of the heavy shipping in the port. Heal the Bay works on developing effective capping and removal plans to keep those toxins from spreading” (Heal the Bay). DDT is still highly concentrated in the South Bay area and still contaminating different species of fish. Even after more than 80 years DDT, a toxic insecticide, is still very concentrated and during upwellings, DDT particles come back up and continue to harm marine life. If humans are careless about what is thrown on the floor or sprayed on lawns, it can lead to disastrous affects when it comes to the condition of the ocean's ecosystems, and can endanger life itself leading to a problem that only we can mend.