We are on the cusp of the sixth mass extinction, as estimated the event to be occurring within 2200 years. Scientists have evidences supporting this statement with the extinction rates and magnitudes, and comparing the present conditions to the past “Big Five”—the previous five mass extinction events. Mass extinction is generally known as the forever disappearance of 75% of lives in the globe, therefore species lost is the main driver of such extinction events. With the current high extinction rates and increasing trend of extinction magnitudes, the sixth mass extinction is expected. Such event is mainly due to human impacts: pollution, over extracting of resources, invasion of non-native species, leading to abnormal changes in the Earth system, for instant causing a rapid and anthropogenic increase in atmospheric carbon dioxide level or coextinction of species. With the current situation, the sixth mass extinction might be similar to the Permian mass extinction event, the most disastrous in the past 540 million years. Human may also face extinction, expecting a rapid decrease in human population within several decades.
Introduction
As titled: Are We On The Cusp Of The Sixth Mass Extinction Event? Yes, we are indeed, as we, here defined as all the lives on the Earth at the moment. And it is estimated that the event may occur as fast as 240-540 years (Barnosky et al., 2011). Mass extinction is times when the Earth loses more than three-quarters of its species in a geologically short interval (Barnosky et al., 2011). In addition, according to the Oxford Dictionary of Geology and Earth Sciences edited by Michael Allaby (2013), mass extinction is defined as the Earth has been taken place environmental catastrophe, removes many gr...
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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
There have been five mass extinctions over the last half-billion years while the sixth extinction is currently being examined by scientists around the world. Studies have shown that this is the most shocking and damaging event since the impact that caused the extinction of dinosaurs. This one is different from all others, because humans are the cause of this disaster to our current environment. If we don’t start to realize this issue and do something about it, eventually it will be too late to try to save the Earth and ourselves. I am going to analyze the sixth chapter, “The Sea Around Us,” for pathos, ethos, visual rhetoric and other related issues
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...be brought to light. In the next thirty years, one fifth of all species will become extinct and in the next one hundred years, 50% of all species will be extinct. This is a staggering statistic and the horror of this is that one species, the human, is the cause of this mass extinction.
Extinction itself has been going on since there were living things to go extinct; it has been part of Earth’s history from the very beginning, starting from the Cambrian extinction that extinguished 92% of all life on Earth, through the more recent Mesozoic extinction that wiped out the dinosaurs, and finally the pre-Cenozoic extinction that occurred at the end of the last Ice Age. Our planet has lost millions of unique species that will never be seen (outside of the imagination of artists and film special effects specialists) again. Extinction is a normal part of the natural world, and the Earth regularly purges pr...
Long-term survival of a species depends on its ability to adapt to changing environmental conditions (Murphy, 1994). Genetic diversity within a species, which has taken 3.5 billion years to evolve, makes adaptations to these changing environments possible. Unfortunately, the rate of extinction of genetically diverse organisms is rapidly increasing, thus reducing this needed biodiversity, largely due to the human impacts of development and expansion. What was an average of one extinction per year before is now one extinction per hour and extinct species numbers are expected to reach approximately one million by the year 2000 (WWW site, Bio 65). As a result governmental and societal action must be taken immediately!
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Several mass extinctions have occurred during the Earth’s history. The Cretaceous – Tertiary Boundary (K-T) Extinction caused the loss of at least three-quarters of all species known at that time including the dinosaurs. The cause of this mass extinction is a controversial subject among scientists but the fossil evidence of it’s occurrence is abundant.
middle of paper ... ... Oxford, Manchester: Manchester University Press. Dreary, T. (1994). The Species of the World.
Our Earth has experienced five mass extinctions that were caused by natural disasters such as comet or meteor showers impacting and destroying sections of the Earth, the shifting of continents caused by the shifts of platonic plates and climate changes such as the end of the ice age that caused certain species to die out. These mass extinctions happened over a long period of thousands of years and not in the concentrated 200 years of drastic geological and biological changes that have caused scientists to believe that we are now living in the 6th mass extinction. Annenberg Learner (2013) says
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.
other species to go extinct as well. Humans can be held responsible for the temperature change
... present rate of human population growth, we might well be heading for the sixth mass extinction crisis.
Lotze, Heike K., Marta Coll, Anna M. Magera, Christine Ward-Paige, and Laura Airoldi. "Recovery of Marine Animal Populations and Ecosystems." Trends in Ecology & Evolution 26.11 (2011): 595-605. Print.