During the late Pleistocene era, which lasted from about 18,000 to 10,000 years ago, North America was filled with giant mammals. These mammals were known as the Pleistocene mega-fauna. At about 10,000 years ago, almost all of these huge animals disappear. Why? There are two main hypotheses on this phenomenon. The first one is the Pleistocene Overkill hypothesis. This states that the human beings that inhabited North America at the time hunted and killed off all of the great mammals. The second hypothesis is the Climate Change hypothesis. This states that the animals died off due to a drastic change in climate when the glaciers from the ice age melted. Evidence is strong for both of these hypotheses. Which one is correct? Further studies must be done to find out for sure, but one can make his/her decision based on the facts that are known.

Between 18,000 and 10,000 years ago at the height of the last ice age in North America the land that was not covered in ice looked like a giant park with many mixed trees and grasses. During this time giant mammals roamed the North American continent. There were

An extraordinary amount of mammals became extinct in North America during what is called the late Pleistocene era, which includes the time before, during, and immediately after the last ice age (This is between 18,000 and 10,000 years from the present day). In North America, eight different mammalian genera were extirpated from North America, and 27 mammalian genera vanished completely. Ice ages, where large areas of continental land are covered with glaciers, have occurred repeatedly during the earth's history. The last time that glaciers covered North America was from about 132,000 years ago to about 10,000 years from the present day. Changes in climate account for the advance and the retreat of the glaciers. Because the late Pleistocene extinction occurred so long ago, and involved so many species, it is difficult for scientists to be absolutely accurate about when they occurred. The best estimates are that the extinctions occurred about 12,000 years ago while the glaciers were retreating. There has been great debate about what caused the extinction of these large mammals. Some people, such as Paul S. Martin, believe that humans, the Paleo-Indians, drove the mega-fauna to extinction by hunting them. The other widely accepted theory is that the animals went extinct due to a large climate change.

There are also some problems with the climate change hypothesis. The first problem is that animals such as mammoths, sloths, mastodons, and others that went extinct during the Pleistocene era had survived similarly warm periods during previous interglacial periods. The second problem is that new world horses, which went extinct at the end of the ice age, are thriving in the same climate today. Just as the overkill hypothesis is not perfect, neither is the climate change hypothesis.

Along with all of these huge mammals, there is also the presence of another significant species, man. At this time the Paleo-Indians are roaming the North American Continent too. These peoples are using beautiful fluted points to hunt the bison, the mastodon, and other mega-fauna in the park like lands of North and South America. These people worked very little, only about eight to ten hours a week, yet they live very well. Plenty of game and vegetation was theirs for the taking; it is a world of plenty. Then, without warning, just a thousand years later, the huge ice caps, mammoths, sloths, horses, the carnivores that ate them, and the Paleo-Indians are all gone, they have vanished from existence. The climate is similar to the way it is today. The parklands are gone. There are belts of closed canopy forests on the coasts and vast grasslands in the center of the North American Continent. (Martin L.D. 1978)

It is easy to make an argument for either one of these explanations as to what caused the great Pleistocene mega-fauna extinction. It could have been the result of over hunting by the Paleo-Indian culture or it could have just as easily been the result of the drastic climate change after the melting of the glaciers. Either way you look at it, it makes sense. However, either side you take also has its holes in it. In order to figure out what really and truly happened we would have to travel back in time and watch the event unfold with our own eyes. But, without that, we still have the fossil record and other scientific techniques to rely on in order to help us piece the puzzle together. In my opinion, it was the Paleo-Indians that caused the mass extinction. We as humans are the exception to the rule when it comes to the preservation of our natural habitat. While all other species attempt to establish equilibrium with their environment in which they, and all of the other species around them can survive, humans always seem to destroy everything in their paths. We bleed our natural resources dry, we hunt off and kill certain species un

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Approximate Word count = 2610
Approximate Pages = 10 (250 words per page double spaced)