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The presence of chemicals in the environment is affecting the prospects for some animal species as well. In 1962, biologist Rachel Carson warned in Silent Spring that the continuing use of DDT could threaten the survival of predatory bird`s, such as bald eagles and peregrine falcons, because of its effect on eggshell formation. More recently, there is growing concern that a family of synthetic chemicals associated with pesticides and plastics, so-called endocrine disrupters, could be affecting the reproductive process in some species of birds, fish, and amphibians.

The global atmosphere also faces growing stress. As our fossil – fuel – based global economy has expanded, carbon emissions have overwhelmed the capacity of natural systems to fix carbon dioxide. The result it a buildup in CO₂ from roughly 280 parts per million at the beginning of the industrial era to 363 parts per million in 1998, the highest level ever experienced. This buildup of CO₂ and other greenhouse gases is responsible for rising temperatures over the last century, according to leading scientists. The 14 warmest years since record – keeping began in 1866 have all occurred since 1998 is projected to be both the highest ever and the largest annual increase ever recorded.

If the world stays on the present fossil fuel path, atmospheric CO₂ concentrations are projected to reach twice pre – industrial levels as soon as 2050 – and to raise the Eart`s average temperature 1-3,5 degrees Celsius (2-6 degrees Fahrenheit) by 2100. This is expected to bring more extreme climate events, including more destructive storms and flooding, as well as melting ice caps and rising sea levels. A new computer simulation by Britain's Hadley Centre for Climate Change in late 1998 projected major reductions in food production in Africa and the United States as a result of climate change. The Hadley scientists also identify the potential for a «runaway» greenhouse effect after 2050 that could turn areas such as the Amazon and southern Europe into virtual deserts.

The global climate is an essential foundation of natural ecosystems and the entire human economy. If we are entering a new period of climate instability, the consequences could be serious indeed, affecting virtually all of Earth`s ecosystems, accelerating the pace of extinction, and leaving few areas of economic life untouched.

Even in a high – tech Information Age, human societies cannot continue to prosper while the natural world is progressively degraded. Our food crops and medicines are derived from wild plants, and even genetic engineering is based on rearranging the genes that nature has created. Moreover, our crops, industries, and cities require healthy ecosystems to store our water and to maintain a nurturing climate. Like the early residents of Easter Island, we are vulnerable. But them, we can see the problem coming.