Prior to humans inhabiting a significant surface of our planet, wildfires would burn out of control until the rainy season came, volcanoes would spill pollutants, and so forth, weeds would grow out of control, animals would multiply until they would starve to death, crude oil and natural gas would spill out of the earth (like they still do in Iran, and in the ocean coast of California), overabundant fish would urinate in the rivers until they would die of nitrogen poisoning, etc.
Some people refer to those as the golden days, and want to depopulate the earth (of humans) down to half billion to 2 billion, depending on how many slaves they think they need (westerners for the brains, Chinese for laborers, Mexicans for agriculture), so the ruling elite can go hunting wildlife in pristine forests, and fly their jets in clear blue sky, while the slaves ride bicicles and busses to their jobs, reproduce with gov't permission only, after careful genetic screening for desirable traits, such as ability to work long hours on minimal food, and then are euthanized at the end of their useful lives, after a symbollic 2 year retirement.
Attention: TDR Forum Junkies 
