Importance of question for archeological research:
Introduction
It's hard to say that humans haven't had an impact on their environment. Climate change, for example, has been a hot issue in the developed world ever since evidence proving the existence of human-caused global warming was unleashed leading to an onslaught of theories regarding its potential effect on our future. But what impact did humans have thousands of years ago when they were first colonizing North America?
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.
In order to better understand these "implications," it is necessary to define and explain the major theories regarding North American megafaunal extinction. The two most widely supported theories are those of environmental change and overkill. Two theories finding less support within the field are those of hyperdisease and "keystone herbivores."
Theories and Proposed Implications
Paul Martin, the most famous and frequently cited proponent of the most popular North American overkill or "blitzkrieg" theory proposes the following ideas: 1) the disappearance of megafauna followed within 1,000 years the proposed first introduction of man into North America (Martin P. S. 969). 2) Kill sites are nonexistent for the majority of extinct megafauna because the prey was so ill equipped to deal with the Clovis hunters that they did not have to be tricked or trapped and disappeared s...
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...he Keystone Megaherbivore theory uses evidence from extant African large herbivores to suggest that the loss of a (352
Owen-Wilson suggests that wile megaherbivores are not particularly prone to disturbance by predators or the weather, their populations tend to grow up until the point of nutritional deficiency which curiously leads to other vegetation components being trampled or broken by the trampling of megaherbivores (Owen-Smith 355). Sometimes, such damage can actually lead to the creation of different landscapes that provide a "higher biomass of accessible forage" (Owen-Smith 355). However, not all land lends to this kind of lucky damage and megaherbivores can also severely decrease the biomass of accessible forage. In fact, whether or not the megaherbivore will help or hinder is largely dependent on the water resources in the trampled areas (Owen-Smith 356).
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
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
The causes of rising conservation include overhunting, recognizing its importance. These newfound awareness results in new policies that preserve everyone equally. When people started to see the decline of wildlife animals including bison and many colorful birds it caused a rise in conservation. A cause of the extermination of bison is “From the Great Slave Lake to the Rio Grande, the home of the buffalo was everywhere overrun by the man with a gun; and, as had ever been the case, the wild creatures were gradually swept away, the largest and most conspicuous forms being the first to go. ”(Doc.2)
“Sex, Drugs, Disasters, and the Extinction of Dinosaurs” is written by Stephen Jay Gould, professor of geology and zoology at Harvard. This essay is one of more than a hundred articles on evolution, zoology, and paleontology published by Gould in national magazines and journals. It tells about scientific proposals for the extinction of dinosaurs – a confusing but an exciting problem that humanity tries to solve. By analyzing and describing each of the claims for the reptiles’ demise – sex, drugs, and disasters – Gould differentiates bad science from good science and explains what makes some theories silly speculations, while the other, a testable hypothesis.
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.
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.
Rapidly evolving throughout the late Pleistocene to the early to mid Holocene, hunter-gatherer-fisher societies hunted megafauna creatures in a systematic and ethical way. When one species migrates to a different ecosystem, that species is not usually recognized as a threat to other species. Survival, during the late Pleistocene and Holocene era, was one of the most important aspects to life. Any organism, regardless of size, living within their environment had to stay alive and reproduce. During these two eras, it seems...
Neanderthal Extinction Neanderthals and modern humans coexisted for well over 100,000 years. Then suddenly Homo neandertalensis began to die out and surrender the earth to Homo sapiens. Paleontologists and anthropologists have entertained several possibilities for the causes of this event: interbreeding among Neanderthals and humans, competition for natural resources, and Darwin’s theory of “survival of the fittest.” What the real cause has been has plagued scientists for years. Now, due to an international research team from Germany, those possibilities have been even further deduced, making it easier to pinpoint the exact reason Homo neandertalensis became extinct.
Andrew Isenberg said that “the destruction of the bison was not merely the result of human agency but the consequence of the interaction of human society with a dynamic environment.” Humans and nature both played a large role in the ultimate demise of the bison.
To bring the readers to his level of understanding, Welz explains every term that may be new to the reader to avoid any confusions. For example, Welz defined the word "de-extinction" during the start of his writing as the whole point of the article depends on the meaning of the term. The author provides reliable sources to support his points which add plausibility to his article. By way of illustration, Welz uses the journal "Radiocarbon" written by S. L. Vartanyan in 1995 in St. Petersburg State University as a source to support his claim that wooly mammoth had gone extinct forty thousand years ago. This paper was presented at the 15th International Radiocarbon Conference, 15-19 August 1994, Glasgow, Scotland (Vartanyan) which represents that experts had proposed it. Also, the point that he provides the sources to give credit to other researchers deduces that he is a sincere scholar and is fair in his writing. Such collection of substantiated sources shows the sincerity of the author and strengthens the writer’s
In spite of the overwhelming amount of negative speculation, the practice of de-extinction might potentially produce some positive ramifications. According to Stewart Brand, a writer for National Geographic, humans should bring back extinct species “to preserve biodiversity, to restore diminished ecosystems...and to undo harm that humans have caused in the past.” If humans were to tamper with nature and bring back an extinct animal, desolate ecosystems which previously thrived, such as deserted islands, could be partially restored through their
People today use hunting as a sport. Of course, not everyone agrees with hunting, but those who like to hunt justify their actions by saying that they are helping with the overpopulation of animals, like deer. The truth is that we are affecting the population of animals. Animal overpopulation can be due to the loss of an animal’s natural predator. Predators are extremely important in an ecosystem, and they are nature’s way of controlling the animal population. In William Stolzenburg’s book, Where the Wild Things Were: Life, Death, and Ecological Wreckage in a Land of Vanishing Predators, he addresses the importance of predators in an ecosystem. He discusses an experiment done by a zoologist named Robert T. Paine. Paine decided to do an experiment to see what happens when one disrupts an ecosystem. He conducted his experiment on rocks along the shore in which a species of starfish was the top predator. Paine’s experiment consisted of grabbing the starfish off the rocks and throwing them into the ocean. His results showed that one single species has a tremendous effect on its ecosystem. After getting rid of the top predator, about half of the species that
The most significant event of the Cretaceous era came at its end. Nearly 65 million years ago, the second most severe mass extinction in earth’s history occurred. This resulted in the loss of around 80% of species living at the time. Though nowhere near as severe as the end-Permian mass extinction, the end-Cretaceous extinction is the most well known mass extinction event. This is due to the violent event that caused it the extinction, as well as the chapter of earth’s history that it closed: the Dinosaurs. The Cretaceous Event ( often shortened to K-T event) Of the animals that were killed off were the flying reptiles (pterosaurs) and the last few mosasaurs and plesiosaurs, both early marine reptiles. Many mollusks and species of microscopic plankton were killed. Terrestrial plants suffered mass extinction as well. Almost 60% of terrestrial plants were lost. This led to high extinction rates among insect populations, especially insects that were highly specialized to feed on just a few types of plants had it the worst. It took approximately 9 million years for the global insect populations to recover from the Cretaceous extinction. Immediately after the extinction, the earth saw an explosion of short term species who respond well to fire, or other external disturbance. Evidence of the catastrophe comes from a thin rock layer deposited worldwide just after the impact. It is dominated by fossil plants whose descendants recover quickly after fires of other disturbances, such as Fire Weed in Alaska. The causes of the Cretaceous extinction are still being debated by paleontologists. Scientists agree that the main cause of the extinction was a...
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.
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