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Many of the world`s scientists believe we are in the middle of another great extinction event. Such extinctions have happened periodically throughout Earths history of life. Most infamously is the K-T (Cretaceous Tertiary) event, which killed of our beloved dinosaurs. Pacing back in time, there were five known events; one at the Triassic (which may have gave way to the rise of the dinosaurs), another at the end of the Permian that produced a vanishing of species (approx 95%) never equaled until today as some will argue. Yet still other extinctions, occurred during the end of the Devonian and Ordovician periods. These past events have happened "naturally" to the history of life on the planet. Root causes taking center stage are large comet or asteroid impacts, deadly disease transversing the continents and huge amounts of volcanism; all in combination with or in addition to, global climate change of the planet. The extinction event of today however is different, as many believe homo sapiens are the main culprit, unfortunately this is not our first time at bat on the extinction mound. The disappearance of the mega-fauna during the late Pleistocene may have been our first go at eradicating entire species of animals from the planet. However, questions arise, did we act alone or with an outside accomplice? Did we even play a part or did nature simply run its course? As far as we know, this is the first time in Earth's history, a single species is responsible for the complete vanishing of many others.
One of the greatest debates among scientist today is the root cause of the Pleistocene Megafauna extinction. Human hunting tops the list with certain disciplines of science, archeologist for example who study human prehistory (the Clov...
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... (Barnosky et al., 2004)
Rapid body size decline in Alaskan Pleistocene horses before extinction
R. Dale Guthrie Nature Sept 2003
(Guthrie 2003)
Range sizes and shifts of North American Pleistocene mammals are not consistent with a climatic explanation for extinction
(Brigid S. Grund, Todd A. Surovell and S. Kathleen Lyons) (Grund, et al., 2012)
Extinctions of herbivorous mammals in the late Pleistocene of Australia in relation to their feeding ecology: No evidence for environmental change as cause of extinction
C. N. JOHNSON AND G. J. PRIDEAUX
(Johnson and Prideaux 2004)
Was a hyper-disease responsible for the late Pleistocene megafaunal extinction?
Ecology Letters (2004) 7: 859–868
(Lyons, Smith, Wagner, White, Brown)
Palaeolithic extinctions and the Taurid Complex
W. M. Napier 2010 February 21
Copyright of Monthly Notices of the Royal Astronomical Society
The Smilodon, the most recent type of saber tooth cats, went extinct about 10,000 years ago, around the time when Pangea began separating and breaking up. Sabertooth Cats did not go extinct due to lack of prey. However, around 12,000 years ago (end of the late Pleistocene) sabertooth cats, american lions, wooly mammoths and other gigantic creatures considered the “megafauna” went extinct. A die-off called the Quaternary extinction. A popular theory for the extinction is that the changing in climate during the end of the last ice age, human activity, or a combination of both killed off most large
Martin is confident that the extinctions must have been caused by “something outside the normal experience of mammals.”
The question of what caused the extinction of megafauna during the Late Pleistocene period is one that archaeologists have struggled to answer for decades, but why should it matter? Discovering with certainty the cause of megafaunal extinction would simultaneously prove or disprove any of the proposed implications of each existing theory regarding this massive extinction.
The re-wilding of North America is basically a conservation strategy (Donlan 2005), aimed at restoring the Pleistocene era (Donlan 2005, Rubenstein et al. 2006). This could be achieved by reintroducing African and Asian megafauna, these species are phylogenetically known to be direct descendents of the extinct Pleistocene species or animals of similar taxa (Donlan 2005, Rubenstein et al. 2006). Re-populating North America is essential for both ecological and evolutionary potential (Donlan 2005) and also economic gain (Donlan 2005, Rubenstein et al. 2006). In this paper I will be discussing the main arguments presented by two papers regarding the Pleistocene North America re-wilding. The first paper is written by Donlan (2005), it is a commentary paper in which he proposes the plan of re-wilding North America based on his opinions. The second paper is by Rubenstein et al. (2006), it is a research paper where he outlines some facts contrary to Donlan (2005)’s paper, unlike Donlan (2005)‘s paper his arguments were supported by variety of recent Scientific published papers which are relevant to the topic discussed.
This paper has shown how Homo sapiens had several advantages over the Neanderthals including better diets, better tools and just better luck. The Neanderthals could not survive the harsh climates they were thrust into and eventually died out. In this paper I looked at how Homo sapiens and Homo neanderthalensis had co-existed but the disappearance of the Neanderthal ius due in some part to the appearance of the more culturally advanced and genetically superior Homo sapiens. Although the How and Why of how Neanderthals went extinct, it is clear that Homo sapiens had a part in their demise. In the last one hundred and fifty years that we have been studying humans we have seen them come from savage brutes, to Homo sapiens respectable contemporary. If we had not gotten lucky in the past, Neanderthals could be studying us today.
In this period the Earth was very cold and there were multiple glaciers. It was a huge ice age. Scientists say that the reason for the ice age was because of a 100,000-year cycle related to the Earths orbit and shape. Mammals got very big and lived in cold grasslands. These animals were relatives of the elephants. They are mammoths and mastodons. The extinction of these animals was at the same time of the extinction of the ice age.
Fossil records from 12,000 years ago show the appearance of the Large Mammals followed by Paleoindian in Eastern North America. Another piece of the fossil record shows that the appearance of Paleoindian brought about the disappearance of the large mammals. Some people feel that, "there is evidence to suggest that rapacious hunting practice of the paleohunters in North and South America 12,000 years ago may have caused…The demise of the very animals they hunted" (Powell 1987). The evidence Powell suggests is that the extinction of a large mammal is usually followed by the appearance of humans in the fossil record. This coincidence is not only seen in the fossil records of North and South America but Europe and Asia as well. Powell shows that as human populations increased local extinctions of large mammals occurred. This was probably due to the fact that there were not many predators that could hunt the large mammals except man. For this reason it is also highly like likely that man and large mammals did not co-evolve which ultimately resulted in the extinction of large mammals.
Bison have been around for 10,000 years. Their ancestors where known as giant bison and they were hunted by the paleoindians that came over on the Bering Strait. The giant bison however became extinct because the paleoindians hunted them and at the end of the last ice age, most of the vegetation they fed off of was destroyed. Dwarf bison, the bison that are around today, survived the ice age because the dwarf bison were faster, reproduced more rapidly and required less vegetation to sustain them. The destruction of giant bison resembles what happened to the bison in modern day America; accept they had to survive droughts instead of extreme cold.
Hunting has contributed to the extinction of several animal species all around the world, including the Tasmanian tiger and the great auk.
For example, chapter 4 brings up the question of how much Homo Sapiens played a role in the extinction of most of the large marsupial mammals in Australia. The evidence is presented that, after Homo Sapiens arrived on the continent of Australia, “of the twenty-four Australian animal species weighing 100 pounds or more, twenty-three became extinct” (65). This is the type of evidence that cannot be disputed. It is a literal fact that certain areas with large mammal populations experienced a decrease in those populations upon the arrival of Homo Sapiens. Thus it is posited that humans have been a strong antagonist to other species for many thousands of
slow extinction, or did it happen all of the sudden? These questions bring rise to many
== = = Human beings are dependent on the Earth's diversity of species for our survival. Wild species play a vital role in the maintenance of the planets ecological functions, yet everyday on the planet 40-100 species become extinct.
The upper paleolithic era brought us many social and cultural innovations. From the development of art, to the continued development of useful tools and weapons, the people existing in this time were the true forbears of modern human civilization. The advances made in self-awareness are extremely apparent as well, with significant new trends in social networks and personal adornment leading to what would be the foundation of society as we know it. These things combined make the upper paleolithic one of the most important periods of human development.
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.
Everyone’s all seen those wildlife shows on tv. The shows on National Geographic and such, showing animals in beautiful environments, everything lush and growing and nothing at all wrong that could threaten these creatures and places. But, have anyone seen the other side? The side where all these beautiful creatures and plants starve, are decimated by predators that have never been there before, and sometime even become poisoned by their very own homes and habitats? Of course no one has. That doesn’t mean that its not happening. It is happening, and its happening everywhere. And guess who is to blame? People. Society. Humans as a race pollute the environment, hunt animals simply for their parts, fish way more than humans will ever need just for the sake of money, introduce new species to new places for our own gain, and even purposefully destroy entire regions just for human expansion. And its starting to take its toll. While it is true that nature is constantly in flux and certain species come and go, humans are causing more species to disappear in the past few hundred years then nature has ever caused since the age of the dinosaurs, and therefore it is up to humans to repair the damage caused, be it cleaning the environment and habitats of these creatures, or taking more direct action to protect and preserve the species that are on the brink of extinction.