Monday, September 16, 2013

10 Biggest Extinction Ever Happens on Earth

Age of the earth is very old indeed. various life cycle path is laid. course on the basis of archaeological and historical remains. Extinction following 10 Biggest ever happened on earth.
Life is a struggle for survival. Animals live under constant pressure to get enough food to eat with the best to adapt to the environment in which they live.
Creatures that do not adapt well to be vulnerable in times of hardship, hunger and plainly regeneration will fail eventually extinct.
Throughout Earth's history, life continuously has taken new forms of event that will continue to examine the creature that became survival
When climate change or the environment drastically, many animals are less able to adjust to the new situation will be extinct.
Mass extinction when most life on earth has disappeared completely, leaving no further fossils or descent. This event has been going on since almost the beginning of the first appearance of life itself. All animals alive today are just descendants of creatures who have been fortunate enough to meet the requirements of adaptation to the world every time they are changed.
And here's ten of the largest extinction in Earth's history.

10. Extinction in the Last Day of Ediacaran
During the period, complex life began to take shape for the first time on Earth.
Micro bacteria Eukaryotes evolved into a more complex and specialized, some of which are grouped together to increase their chances of finding food and avoiding predation.
Most of the strange creatures do not left a note because they do not have a skeleton, they tend to be shaped soft rot when dead and not a fossil.
Only in special circumstances, these creatures can be fossilized. such as dead and lying in the mud that hardened suddenly, leaving a trail
Some fossils tell us of some of the sea is full of strange and alien creatures that resemble modern worms, sponges, and jelly. However, these creatures depend on oxygen, as we did. Oxygen levels began to fall on the earth and in the world of mass extinction 542 million years ago. More than 50% of all species died. a large amount of decaying dead creatures into fossil fuels (oil) at this time.
The exact causes of decreased oxygen levels are not known, however, these mass extinctions make room for the Cambrian explosion, more complex ones outside of just a mere form of worms.

9. Extinction in the Cambrian-Ordovician Age
 During the Cambrian period, life evolved. Edicaran life has remained unchanged for millions of years, but suddenly in the Cambrian diversification and evolve into new forms without end.
Exotic crustaceans and trilobites became the dominant life in large and diverse. Giant clams and arthropods water, similar to insects, filled the seas.
These creatures have a rigid exoskeleton that left a gift of fossils for us to learn.
Life growing up more than 40% of all species suddenly became extinct 488 million years ago. Those who persist in conditions as some tough changes that occur.
Scientists do not yet know exactly what form of this change. One theory suggests that the glaciation occurred, the coldest part of the ice age.
We have been enjoying the interglacial period, the hottest part of the ice age, for the last eleven thousand years.
Extreme temperature changes can easily cause the extinction of a large number of lives. This extinction event marks the boundary between the Cambrian and Ordovician period era.

8. The extinction in the Ordovician-Silurian
Life began to flourish once again during the Ordovician period. Nautiloids (primitive octopus), trilobites, corals, starfish, eels, and jawed fish fill the seas.
Plants struggle to survive on land. Life is gradually becoming more complex.
443 million years ago, more than 60% of the living dead in what is considered the second largest extinction in Earth's history. It is caused by a rapid ice age due to reduced levels of carbon dioxide.
Most of the water that is home to an abundance of life becomes depleted in icecaps and glaciers which in turn leads to lower oxygen levels too.
It is estimated that gamma-ray bursts from space have destroyed the ozone layer and unfiltered solar ultra-violet radiation and then destroy most of the life of the plant, which causes the initial decrease in carbon dioxide. Although some creatures survive and continue to live, the number of species that will need more than 300 million years to recover from this event.

7. The Lau event
After Ordovician extinction , Silurian period begins. Life recovering from the last mass extinction and this period is characterized by the development of true sharks and bony fish, most of which appear perfect and modern.
Moss and small plants finally started to grow freely on land along the shoreline, and some arthropods evolved into spiders and millipedes are adapted to dry air and live side by side with land plants.
number of giant sea scorpions abound, and trilobites continued to dominate. 420 million years ago, there was a sudden climate change that caused the extinction of 30% of all species. Atmospheric gases change in the proportions that make a lot of things can not adjust and even poisoning
Cause of these changes is unknown. Struggling to live up to the Silurian period ends and Denovian period begins, when evolution produces different models of evolving life.

6. Extinction in the Late Devonian Period
Devonian period is a certain fish evolved with solid fins.
At sea, extensive coral reefs filled with fish and sharks, some of whom ate trilobites.
Trilobites losing their foothold as the dominant sea creatures for the first time since they appeared more than 100 million a year earlier.
In fact, sharks are so successful that they do not need to adapt to change much to survive. and several modern shark looks almost exactly like the Ancient Sharks.
Seed land plants evolved and diversified. More developed complex land plants and the soil appeared for the first time in history.
Strange forest mushroom growing has a height of 8 m, which is sadly now extinct. 374 million years ago, 75% of all life is death . This is due to changes in atmospheric gases, probably due to massive volcanic activity or meteorite impact.

5. The disappearance of the Carboniferous Rainforest
After the coming of the Devonian Carboniferous period. some land animals develop terrestrial eggs, which enables them to live almost anywhere in the ground instead of being limited to the beach where they can lay eggs. Winged insects emerge and prosper. Sharks enjoyed a golden age and a few survivors of the extinction of trilobites are becoming increasingly rare.
Giant trees appear and extensive rainforest cover most of the ground, increasing the oxygen content of the air up to 35%.
By comparison, today 21% of the air is oxygen. Conifers of the Carboniferous period remained virtually unchanged today. 305 million years ago, the ice age caused a sudden brief carbon dioxide levels to be the lowest in the history of the Earth.
Large forest die and with them, many land animals also die. Nearly 10% of all species on Earth disappeared at that time. The trees rot, lumpy, and is now a major source of carbon fuels for us, which is also the name of this period.

4. The Permian-Triassic extinction
After the collapse of the rain forest, the most successful animals that live on land are those that lay eggs.
This species rapidly dominate other species before it has a chance to recover and their diverse, producing a wide range of reptiles and synapsids dominant, the reptile-like mammals and also the ancestors of mammals.
252 million years ago, Earth's disaster that has never been seen before and never seen again. This is caused by a meteorite impact or volcanic activity that radically changed the composition of the air. Between 90% to 99% of all life extinct. This is the largest mass extinction in history, and is known as "The Great Dying".
For reference, let's look at the animal extinction caused by humans. During our time, high estimates indicate that we have caused nearly 1000 species of animals become extinct. and There are approximately 8 million species alive today, which means that even under the most pessimistic estimates, we have eliminated 0.01% of all animal life. Although this was not proud of, but the number is very small when compared to the nature of mass extinction of life on the early Earth

3. The Triassic-Jurassic extinction
After the devastation caused by the end of the Permian period, reptiles and dinosaurs became dominant again appear. Dinosaurs are not dominant over the other reptiles, and dinosaurs in this period no bigger than the horse. And Dino Nation who became famous because of the size and shape is creepy to this day their descendants
All larger dinosaurs, tyrannosaurus, stegosaurus, triceratops, and the giant long-necked sauropods, came in the days of Jurassic or Cretaceous period.
205 million years ago, 65% of the Triassic dead, including all large land animals. Many dinosaurs survived because of its small size. Most mass extinctions last one million years or more, but this one just takes ten thousand years. This is probably caused by a massive volcanic eruption that spewed massive amounts of carbon dioxide or sulfur dioxide, which cause abrupt climate change.

2. The extinction of late Jurassic Period
During the Jurassic period, giant marine reptiles like the Plesiosaur dominated the ocean. Master pterosaurs and dinosaurs roamed the Earth sky. Stegosaurus, Diplodocus long, and a great hunter allosaurus common. Conifers, cycads, ginkgoes, and ferns growing in a dense forest.
Small dinosaur and bird feathers began to have started to emerge. 200 million years ago, 20% of this life suddenly disappeared from the fossil record, most of the marine species.
Shells and corals have been dispersed, but they almost completely disappeared. Few survivors managed to replenish the sea gradually over millions of years. Extinction does not greatly affect land animals, and only a few species of extinct dinosaurs.
Exclusive cause of extinction in the ocean is still a matter of debate, but one possibility is that the tectonic ocean plates sink a little more so as to make the deeper ocean.
Creatures in the ocean that were previously adapted to the shallow depth of many who perished in the sea getting in and kept away from the surface.

1. Extinction at the Cretaceous Tertiary Period
It is the most famous extinction event. After ending of Jurassic, dinosaurs continue to proliferate and evolve over the next period of the lime. They specialize in the many forms that we know today
More importantly, it was only during the period of chalk that alive finally recovered from the extinction of the Early Ordovician-Silurian. Growing number of species eventually exceed the amount of the Ordovician period, 300 million years earlier, for the first time. Synapsids eventually evolved into a small, rodent-like creatures, which is the first mammals appeared.
65 million years ago, a large meteorite impact at Chicxulub fallen to the earth (now called Mexico), disturbing the atmosphere and causing global warming that worse, in turn, kills 75% of all species.
These meteorites contain large amounts of iridium, which is usually very rare on Earth, and on the surface of the rock world 65 million years old shows a thin layer of iridium rest of the impact of these events.
A group of small reptiles and mammals species were among the survivors of the extinction. Mammals and dinosaurs began to replace the role as the dominant animal on the land surface. - 10 Biggest Extinction Ever Happens on Earth

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