It produced large volumes of carbon dioxide that caused global warming. The eruptions burned forests four times the size of Korea. Volcanic eruptions that continued for 1 million years released around 300 million square kilometres of lava while more than 1750 metres of sediment was formed in the Siberian Traps. The formation of the giant continent Pangea caused immense changes in geology, climate and the environment. The third period of extinction, around 251 million years ago, during the Permian Age, was the biggest and worst that ever happened on Earth. These changes caused around 75% of living creatures to die.Įxtinction in this period impacted life in the sea which, at the time, was dominated by corals and stromatoporoids. Other causes include a drastic decrease in oxygen levels globally, the increased activity of tectonic plates, and climate change. A relentless meteor shower is believed to be one of the causes of mass extinction. The second period of extinction, during the Devon Age, happened around 359 million years ago. Some of the organisms affected by the first extinction were Brachiopods, Conodonts, Acritarchs, Bryozons, and also Trilobites that lived in the ocean. Some 86% of the population of living beings disappeared within three million years. Subsequently, the level of carbon dioxide in the atmosphere and in the sea dropped, causing the number of plants to decrease dramatically and an ecosystem chaos ensued because certain plants, used as sources of food, became scarce. The temperature dropped drastically and ice formed everywhere, lowering the water level. However, towards the end of the period - around 443 million years ago - everything changed suddenly, when the old continent Gondwana reached the South Pole. First period of extinctionĮntering early to mid period of the Ordovician Era, the Earth was still warm with an ideal humidity level for living. However, according to fossil records, only five eras have drastically reduced the population of living beings on earth to warrant the label of mass extinction. ![]() There are have been many periods of extinction, from when the first organism emerged on Earth until today. ![]() The Earth is no stranger to disappearing life forms. They argue that with more than seven billion people, human activity has drastically influenced nature and the extinction of a number of wildlife. More recently though, a number of scientists have argued that because of the nuclear bomb testings of the 1950’s and population explosion, humans have entered a new era, called the Anthropocene. We are currently in the Holocene era, which started around 11,700 years ago when the Ice Age ended. Geologists divide the periods from the Earth’s formation up until now into a number of eras based on the changes that happened in each of them. Since then, bacteria has evolved into more complex forms, though different beings have also become extinct.
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