What Evidence Exists To Indicate That Prehistoric Humans Had Destructive Impacts On The Environment?

AIA1000-World Prehistory

Major Essay Question: Option 3

What evidence exists to indicate that prehistoric humans had destructive impacts on the environment?

What evidence exists to indicate that prehistoric humans had destructive impacts on the environment?

In recent years, humans have become increasingly concerned with their effect on the planet and its ecosystems. While it is probably true that our impact on the environment on a global scale has never been as great, the difference to prehistoric times is simply due to our increasingly sophisticated technologies and our ever increasing population. It is tempting to believe that our predecessors lived in complete harmony with nature but evidence conducted in this field shows this not to be the case. From the very beginning of human life, people altered their environment. The key is to differentiate between natural impacts and human impacts on the ecosystem, a problem that has left countless researchers offering strong arguments for and against the idea that prehistoric humans led destructive lives.

Many of the challenges we face today-deforestation, soil erosion, desertification and salinization were problems even in ancient times. Archaeologists have evidence that small hunting and gathering groups in various parts of the world used fires to get rid of unwanted vegetation, to flush out game and to help fertilise the land to allow for new grasses to grow for their game. The earliest probable evidence of fire being used deliberately to clear forests was 60,000 years before present in the Kalambo Falls site in Tanzania (Grove, 1995). An example of the use of fire can be found on our very own shores. It is believed that 50,000 years BP human use of fire had altered vegetation patterns and perhaps even climatic patterns enough to cause extinction of numerous large mammals, called "megafauna" (Harris, D and Hillman, G, eds, 1989). Fire was used for various reasons, forcing animals to flee allowing for easier hunting, creating new grasslands, permitting the open spaces necessary for both ritual walkabouts and easy transportation in densely forested landscapes. In the short term this created an environment favourable to their needs, in the long term it created an arid environment less favourable to humans. This use also created problems with animal species that depended on plant species not favoured by this burning. An example of this is the 80-100 kg flightless bird, Genyornis Newtoni. This bird relied on the plants, which grew at the edge of wooded areas, plants which were more likely destroyed during the fires. Using amino acid racemization, a reliable dating method, on pieces of Genyornis Newtoni eggshell, Glenn Miller and his team discovered that this bird disappeared from the entire continent 50,000 years ago. Another group of scientists led by Richard Roberts demonstrated that multiple species went extinct in a stable climate and within 10,000 years of the arrival of humans. Taken together, these two reports show that the megafaunal extinctions could be linked to human action, primarily burning (Harris, D and Hillman, G ibid.)

The Tigris and Euphrates rives begin in the mountains of Turkey and in ancient times were known as Mesopotamia. By 3000 B.C the city-states of southern Mesopotamia had formed the world's first civilisation, called Sumer. In the early 20th century, archaeologists in Mesopotamia puzzled over the barren desert that had once been a rich and powerful civilisation. Over the centuries, silt carried by the Tigris and Euphrates built up the streambeds. Eventually, the surrounding farmlands were below the level of the rivers. The Sumerians constructed levees to contain the rivers but the irrigated waters went to the fields and collected on the surface. The hot sun evaporated the standing water and left behind layers of salt. The soil also became waterlogged in places and caused the water table to rise, bringing more salt to the surface. Salinization is the only solution to this problem but the rulers of Sumer based their wealth and power on the skills and labor of ever growing population and ordered the farmers to continue irrigating to produce more food. By 1800 B.C agriculture in southern Mesopotamia had almost disappeared, leaving an impoverished people who lived on a desolate and poisoned land. The world's first civilisation had created a monumental environmental disaster. This pattern of shortsightedness continued in other areas of the world. In the Indus River Valley of India, agriculture arose around 2300 B.C. Another vast irrigation system caused soil salinization and combined with their clearing of hillside forests for use in their huge kilns, the people of the Indus River Valley civilisation abandoned their once-impressive cities.

Ancient Greece and Rome also had their fair share of environmental use and abuse including; deforestation and overgrazing, destruction of wildlife, erosion of land, pollution of air, land and water, depletion of resources and so on. Taking too many animals and plants of a critical species resulted in the reduction of numbers or even distinction, and such events occurred in the past history of every group. Although the different groups set prohibitions against the indiscriminate slaughter of types of animals and oral traditions which taught rudimentary conservation, hunters and gatherers could not leave nature untouched. It is often believed that the pressure of hunting in the Stone Age led to the extinction of the larger animals of the Pleistocene period or at least acted with the climatic change at the end of the Ice Age (Hughes, 1994). Some animals from the Mediterranean ecosystem were rivals of humans as predators, such as the cave bear and the cave hyena. Some authors blame the hunters and gatherers of environmental damage through their periodic fires, but early hunters believed they were aware of the appropriate times and places to set the fires to most suit their purposes. Although hunters and gatherers made important impacts on their ecosystems, they intended to maintain and often succeeded in maintaining balance with them. Really they had little choice in the matter, since if they damaged the local ecosystem it was they who suffered. Even if they believed they were living in harmony with nature, the written evidence of the time seems to deem otherwise. In one of the most perceptive analyses in ancient times of human impact on the earth, Plato described the deforestation of Attica and the resultant soil erosion, so that "what now remains compared with what then existed is like the skeleton of a sick man, all the fat and soft soil having wasted away, and only the bare framework of the land being left" (Hughes,