During the late Pleistocene, a mystery occurred in which large mammals went extinct in North America while they survived in other parts of the world. Scientists studying the late Pleistocene extinction provided a plethora of explanations, including overkill by humans, extraterrestrial events, and climate changes (Faith and Surovell, 2009). However, there was no unified explanation that they all agreed upon. Taking note of this, J. Tyler Faith and Todd A. Surovell conducted tests to discover whether the extinction was a single event or a long-term process. Their findings were important to other scientists in the same field, as they served as a guideline for their explanations of catalysts of the extinction.
Scientists in this field have primarily focused on the potential causes for this occurrence. The first is the overkill hypothesis. In 2002, Grayson and Meltzer revisited Paul Martin’s hypothesis of the late Pleistocene extinction, which was developed 40 years ago. The hypothesis states that the extinction of late Pleistocene animals is the result of human overkill; Grayson and Meltzer criticize this hypothesis because Martin used evidence specific to New Zealand, in which humans hunted mammals to extinction 900 years ago. Although they did not rule out human overkill for the Pleistocene extinctions, they surmised that other events might have contributed to the extinction (Grayson and Meltzer, 2003). Other scientists such as Alroy have contested this contradiction. Alroy used a computer simulation to compare the changing size of the population of humans and the changing size of the herbivore population during the end of the Pleistocene to support the overkill hypothesis (Alroy, 2001). Meanwhile, Haynes used “black mats”, or or...
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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.
Forsyth, K., Taylor, R., Kramer, J., Prior, S., Richie, L., Whitehead, J., Owen, C., & Melton, M.
Extinction of Dinosaurs Two-hundred and thirty million years ago, the first dinosaur-like creature roamed the earth. Within five million years it could be considered a dinosaur. The sandstones of the dinosaur. They were soon at the top of the food chain. They populated every continent.
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.
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
When I started this paper, I had many questions. I wanted to know what all the main theories of dinosaur extinction are and how many there are. I also wanted to know what factors in each theory would have killed these massive beasts. Other questions I had are: had dinosaurs been dying out before the event? Did any dinosaurs survive the Cretaceous/Tertiary (K/T) event? What religious beliefs contradict the dinosaurs’ very existence? The last question I wanted to address was whether or not an event such as this one could happen to us? After five papers and hours of research, some of the new questions I have are: what happened after the Cretaceous/Tertiary event? I would also now like to know if one of these theories could happen to us and how we would be able to handle it. I came up with these questions because I wanted to know we are living with this present danger. Whether a huge ice age could eradicate an entire population of humans is mind-boggling and would be extremely interesting to research. To come up with these new questions, I let my brain wander. I was joking a...
Thousands of years ago, hunting may have been the cause of the extinction of the North American large land mammals. “Moving up into the 1940’s and 50’s some of today’s most prominent game animals were almost non-existent.”(Kerry G) Over-hunting will directly cause the decline in the particular animal’s species. This will effect everything around it, for example ...
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...
When looking at any mass extinction event, there are a number of questions that will invariably need to be answered. When did it happen? How many species were affected? Which ones were they? What was the cause of such widespread death? How did some species survive while other, thriving ones were wiped out completely? For four of the “Big Five” mass extinction events, the Ordovician-Silurian, Permian, Triassic-Jurassic, and Cretaceous-Paleogene, the answers to these questions are all agreed upon, almost universally. The remaining event, known as the Late Devonian mass extinction, lacks a definitive answer as to the cause.
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of species due to a variety of causes. Included is out competition, depletion of resources
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