Cataclysmic Events Causing Mass Extinction

Five mass extinctions have occurred throughout the history of planet Earth. It is predicted by Author Elizabeth Kolbert, that a sixth extinction may be underway. The Sixth Extinction is a book in the viewpoint of Kolbert and narrates her travels around the globe while she studies numerous wildlife species. Kolbert claims that ¨Those of us alive today not only are witnessing one of the rarest events in life's history, we are also causing it,” (Kolbert, Page 8). Throughout her work, Kolbert claims that numerous species are decreasing in population due to harmful human activities, which could lead to a global disaster.

There have been 5 mass extinctions in Earth’s existence. The names of these are (from most recent to least recent): Cretaceous–Paleogene, Triassic–Jurassic, Permian–Triassic, Late Devonian, and Ordovician–Silurian. The most well known mass extinction, Cretaceous-Paleogene, was theorized to have occurred through a massive comet or asteroid impact. A cold winter created by the impacting object forbid any plants and plankton to carry out photosynthesis. During this time, about three quarters of all life went extinct. This happened approximately 66 million years ago. Most life forms went extinct, with some ectothermic species and tetrapods weighing less than 25 pounds. Although everything seemed to look hopeless, adaptive radiation caused evolution

An extinction event (also known as a mass extinction or biotic crisis) is a widespread and rapid decrease in the amount of life on Earth. It occurs when the rate of extinction increases with respect to the rate of speciation. Extinction occurs at an uneven rate.

I chose to focus on the most recent extinction: The Cretaceous Event. This mass extinction happened at least 65 million years ago and wiped out 76% of the Earth’s species. According to our textbooks there are many explanations as to what happened.The first one states that there had been a comet or asteroid that impacted Mexico’s Yucatan Peninsula and then that caused global destruction and rapid cooling. Another explanation that scientists have come up with is an increase in volcanic eruptions. Both explanations could have lead to the sky being clouded with debris. The Earth was then deprived of solar energy and photosynthesis could not occur resulting in the death of many plants, this then lead to the disruption of the food chain. Other alternative

The earth has been around for 4.6 billion years, and over this time 99.9% of all of the species that have existed on earth have gone extinct. (Barnosky, et al) Palaeontologists characterize mass extinctions as times in Earth’s history when the Earth loses more than three-quarters of its species in a geologically short period of time. This has occurred 5 times over the past 540 million years, and scientists are now suggesting it is happening a 6th time. We are in the midst of a sixth mass extinction that has the potential to wipe out many species of importance, and humans have a profound impact on it.

One reason a mass extinction can be plausible is because a lot of the previous periods have also been caused by mass extinctions. A lot of these extinctions were triggered by some change in the weather or atmosphere. Earth’s climate today, is becoming increasingly warmer and carbon dioxide levels are increasing which might potential be too much for humans and animals to take.

1998). We are left with some form of disruption to the carbon cycle for viable explanations, through methods of elimination. None of the five mass extinctions should necessarily be considered events; rather they have occurred due to the increasing effects of many causes acting in combination over long periods of time – up to millions of years. In all cases, however, some form of agitation of the carbon cycle is

The current extinction event is unusual in that most of the extinctions have been caused by increased communications bringing more species

Mass extinction is a species or an animal that is no longer living. We have loss 75 percent of specie in 2 million years or less that a occur in just 300 years.

It was caused by continued growth of the ice caps and it killed 70 percent of all species. “The third extinction is the most devastating in the planet’s history – as many as 96 percent of all animal species died out during it”(Regenerative. “6 Mass Extinctions.” REGENERATIVE.com, 16 Dec. 2016,). This extinction was 225 million years ago, among the Permian era. A super volcano eradicates most of all life! Of all life currently on Earth is descended from the 4 percent of species that survived this extinction(Regenerative. “6 Mass Extinctions.” REGENERATIVE.com, 16 Dec. 2016,). The forth mass extinction was 200 million years ago in the Triassic era. It was caused by an asteroid crashing into the Mexico’s Yucatan Peninsula (Regenerative. “6 Mass Extinctions.” REGENERATIVE.com, 16 Dec. 2016,). The asteroid through dust and ash in the air and blocking the sun and killing 50 percent of all life. The fifth and final extinction was 65 million

The second, third, and fourth mass extinctions of life were all results of climate change (Eldredge ) Now the fifth extinction is one of the most famous extinctions as far as science and the hollywood scene are concerned. This is the mass extinction that ended the Triassic era. Many theories have been spread far and wide from everything from a giant meteor to a volcanic eruption that ended these dinosaurs. Besides the fifth extinction what do all of these extinctions have in common? They all ended with massive climate change. What is happening on Earth right now? Well its massive climate change…

A Mass Extinction is when there is a rapid decreases in life and biodiversity in a short amount of time. This type of event may be caused by a natural disaster or a fast change in the environment and the animals can’t adapt to it fast enough. The mass extinction of Ordovician-Silurian occurred 445.2-443.4 Million years ago. The end period Ordrivacan and the strat Silurian period. Scientists believe the cause of the event was sea levels decreased because of glaciation; forming glaciers or covering over the African and South American portions of Gondwana. The plant was mostly covered by ocean with the southern half of the supercontinent Panga; Gondwana. The atmosphere was moist and hot reaching 110 Faringht. After 25% of marine families died

From the 17th century to 20th century, over 300 years, countries gradually becoming modern and human civilization developed rapidly. We changed the earth little by little, we paid more attention on how to improve the technique we had, at the same time we forgot to protect our environment which resulted many species of animals are in danger of becoming extinct. From a research it shows there are 16,928 listed endangered and 905 are already extinct.

There have been five well known extinctions on this earth. The one most well known is the mass extinction that ended the dinosaurs. Mass extinction is often described as the elimination of a large number of species in a short period of time. Despite what many think, the elimination of species is almost commonplace at this point. The Earth is currently in the middle of a sixth mass extinction, and it’s been caused by the human race.

Over 98% of all organisms that have lived on Earth are now extinct. A mass extinction event occurs when a large number of species die out within a small time frame (relative to the age of Earth). Mass extinctions are intensively studied for both cause and effect, as there is usually room for debate regarding catalysts that precede the extinction and the massive influx of new biological species that follows. There have been five major mass extinctions, dubbed the “Big Five,” that have wiped out at least 50% of the species living at those times. The most well known mass extinction of the Big Five, with the decimation of every species of non-avian dinosaur, is the Cretaceous-Paleogene