The Effects Of Climate And Low Nutritional Status Of Australian Soils

The scale and pace of change is dramatic; for example, the extinction of species is occurring at around 100-fold pre-human rates4. The population sizes of vertebrate species have, on average, declined by half over the last 45 years5. More than 2.3 million km2 of primary forest has been felled since 20006. About

Over the years many people have made studies of what they believe were the important factors

One criticism of this research is that it is correlational. Therefore, we cannot infer a causal

| The discussion is focused on the topic with ample evidence from the literature. The literature is critiqued. (21.5-25)

It has been suggested that food production has changed some biomes in Australia, from natural systems to systems completely dominated by humans.

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

Humans played a major role in the extinction of large mammals because hunters possibly killed them off. They were also slaughtered with knives and stampeded over cliffs at that time at which their species became less and less. to extinction in a period already providing great stress due to the receding ice sheets as the last glacial maximum came to an end. Later, this would mean a lack of analogues

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.

Second, the reading states that park wildlife was affected as well. In contrast, the professor in the lecture averts that the small plants that grow create ideal

The overkill hypothesis stresses the fact that people were the main technicians behind the late pleistocene extinction of fauna in Northern Eurasia and North and South America. Paul Martin of the University of Arizona and others see a subsequent and spontaneous connection between the presence of people and the vanishing of numerous species of large mammals. According to the overkill hypothesis, the spread of humanity correlates to the extinction of mammals at the same precise location they migrated to. The humans got to be big game

.The first scenario that is given is that climate lead to the extinction of the megafaunas. The article claims that throughout the period in which megafaunas were in risk of extinction a climate change took place. Therefore making it more dier which resulted in a lack of greenery for megafaunas to survive off of. The second scenario given was that due to human hunting megafauna became extinct. Despite the low population of people hunting it is claimed that it still hugely impacted the megafaunas population as they had low reproduction rates. Lastly Hanneke Meijer states that the third possible explanation for the megafaunas could be the combination of human hunting them and the lack of food for them due to climate changes.

However, in response to the inconclusive evidence as basis against the soundness of the L.A.P.D. study supporting the second premise, some may counter that just as

There have been five well known extinctions on this earth. The one most well known is the mass extinction that ended the dinosaurs. Mass extinction is often described as the elimination of a large number of species in a short period of time. Despite what many think, the elimination of species is almost commonplace at this point. The Earth is currently in the middle of a sixth mass extinction, and it’s been caused by the human race.

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