Megafaunas Case Study

The ecological conditions might have changed quickly and the species was not able to adapt to those conditions, which eventually lead the species to go extinct.

2.-transition-habitat loss, climate change, poaching and farming, pollution- the reasons for the decrease ar that their milkweed plants are decreasing, the climate can cause them to migrate at wrong times which causes many casualties, the large usage of pesticides are killing them off fast, and pollution in the air can also cost them their life.

They aren't able to adapt and figure their new environment quickly enough. Documents B, E, and F each tell about a specific organism that was affected by the dramatic climate change, these organisms spend years trying to perfect their home, diet, and children. Document B states, “Organisms are dying out, especially in certain areas where they aren't able to adapt as quickly, but they don't have the chance to do all that work over, so they have to live with that and start over until they reach safety again.

Last, many endangered animals are becoming more at risk because of the climate change. The habitats of several endangered animals have started to disappear, and their water has become scarce, too. Document B says that these animals include snow leopards, whose forest climate is shrinking, one-horned rhinos, whose vegetation is being diminished by regular droughts and floods, and orang-utans, who are being killed in forest fires in their forest homes. This killing of endangered animals is bringing these species closer to extinction all because of the rise in earth’s

S. 969). In order to prove the viability of an overkill theory, Martin constructed a model that would consider both the expanding population of an invading people and the population of megafauna that they are hunting throughout their colonization. He determined that even a very large biomass (in this case the megafauna) of 2.3 X 10^ 8 metric tons could be overkilled within just 1,000 years by a biomass of no more than 10^6 metric tons of Clovis hunters (Martin P. S. 972). Additionally, Martin argued that carnivores that Clovis hunters were not hunting such as the saber-tooth tiger would have become extinct around this time because of the removal of their herbivore prey (Grayson and Meltzer 586).

In the next few paragraphs, one will see the evidence provided by a variety of archeologists and paleoclimatologists onto how climate change caused the breakdown of the beautiful society.

The article discussed the changes in many habitats due to anthropogenic activity. Anthropogenic is an adjective that describes changes in nature due to the people. Next, this article discussed climate change and the impact that it is having on species like clams, and fish due to ocean temperatures rising. The article also addressed carbon dating of fossils to look for cause of extinctions. Human development and agriculture have had a tremendous impact on the population of many species that are terrestrial. Deforestation is a big problem that has caused a decline in the bird species. Commercial fishing in many areas has led to a decline in fish populations. Furthermore this article

Between the scientists and the environmentalists, the theories continue. Let’s face it; no one or no thing will live forever. Big animals eat little animals; little animals eat bugs and plants. The Indians were noted to be a “super-predator” disrupting the normal ecosystem and ultimately causing the extinction of the megafauna. There is no concrete evidence to support this theory yet

When sometimes around twelve thousand years ago climate started to become warmer and ice started to melt, it created a great allowance for ancient hunters to reach North America. Native Americans started to hunt in the wider areas and supply their community with a lot of meat. When people started to have more food, especially meat that caused a fast growth of population. For some unknown reasons, at the same time big mammals and mastodons started to disappear from the Earth. It is a possibility that the climate warming and lack of water sources played a role of the disappearance these big animals. Lack of water put animals in the situation when survival is not possible. The climate change also made a big adjustment in human’s ration and style of life. When people started to spread to North America, they discovered a lot of new food sources like small animals, fish, different kind of nuts and berries.

In his article, “Future Megacity Operations – Lessons from Sadr City” Major Christopher O. Bowers argues that future conflicts will meet the challenges of megacities. The purpose of the article is to show that present lessons from Sadr City can be scaled up and used by U.S. commanders to solve upcoming challenges in a future conflict in a megacity. The article was published in Military Review May-June 2005. Major Bowers served in Sadr City, Iraq, from 2005 to 2006.

The reading suggests that two possible causes: the environmental pollution and predators attacks. However, the lecture defends that is more probabily is the predators attacks.

In the Americas Pavilion of the Toronto Zoo, two species were identified as having different reactions to the same change to the environment. The Giant Pacific Octopus and the North American River Otter are affected differently by the inconsistent climate patterns and the overall warming of the climate.

"We call them dumb animals, and so they are, for they cannot tell us how they feel, but they do not suffer less because they have no words” (Anna Sewell). There is undeniable evidence that animals are being affected by climate change. Even though the effects are difficult to measure, there are many different ways animals are being affected. With the loss of predator and prey species it affects the life cycles in the food chain. The earth’s climate change causes habitats such as snow, ice, or forest areas to alter, resulting in loss of habitat and food accessibility as well as causing extinction.

What is known is that humans used fire for a variety of purposes, such as agriculture and hunting. Humans learned that if a forest was cleared of undergrowth, it was easier to hunt for animals in the forest. In the Australia of 50,000 years ago, there were large animals – termed the megafauna – that the indigenous people hunted for food. Soon after humans arrived on the continent, however, the megafauna disappeared. There are several possible reasons for the extinction. One particularly dramatic one is that humans’ extreme use of fire, perhaps uncontrolled, caused the climate to become more arid, and making it impossible for some megafauna to survive. Possibly, the plants that were their sustenance were destroyed. Some animals – such as a large, emu-like bird – were hunted to extinction. (NPR) The climate of most of Australia is still arid.

Rapid climate change also ends up on the suspect list of possible dinosaur extinction events. During the latter part of the Cretaceous Period continents broke up causing volcanoes to erupt and fill the sky with gas and ash resulting in a drastic climate change (“Dinosaurs Climate Change and Biodiversity”). The shifting of continents changed the Earth’s landscape, altering weather patterns and overall climate (“Dinosaur Extinction Theories”). Also, over a long period of time, climate gradually changed. Ocean habits changed, temperatures grew much more extreme causing scorching summers and frigid winters (Norell, Dingus, and Gaffney). Radical temperature changes like these led to a green-house effect, making life for the dinosaurs a lot