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1. A popular theory explaining the evolution of the universe is known as the Big Bang Model. According to the model, at some time between ten and twenty billion years ago, all present matter and energy were compressed in to a small ball only a few kilometers in diameter. It was, in effect, an atom that contained in the form of pure energy all of the components of the entire universe. Then, at a moment in time that astronomers refer to as T=0, the ball exploded, hurling the energy into space. Expansion occurred. As the energy cooled, most of it became matter in the form of protons, neutrons and electrons. These original particles combined to form hydrogen and helium, and continued to expand. Matter formed into galaxies with stars and planets.
2. The ecosystems of the Earth provide an array of free public services that are essential for the support of civilizations. The maintain the quality of the asmosphere, provide food from the sea, manufacture and replenish soils, recycle wastes and nutrients, control the overwhelming majority of crop pests and disease vectors, and so on. People have no idea how to take over these activities satisfactorily. The do know, however, that the theory oce advanced in the 19th century - that the productivity of the land can be infinitety increased by the application of capital, labour, and science - is wrong. History has shown that once the natural life - support systems of a civilization have been sufficiently damaged, They cannot usually be replaced. The ancient deforestation and overgrazing of the Mediterranean region is a famous example. And today, a global civilization is ruining the global environment.
2. The ecosystems of the Earth provide an array of free public services that are essential for the support of civilizations. The maintain the quality of the asmosphere, provide food from the sea, manufacture and replenish soils, recycle wastes and nutrients, control the overwhelming majority of crop pests and disease vectors, and so on. People have no idea how to take over these activities satisfactorily. The do know, however, that the theory oce advanced in the 19th century - that the productivity of the land can be infinitety increased by the application of capital, labour, and science - is wrong. History has shown that once the natural life - support systems of a civilization have been sufficiently damaged, They cannot usually be replaced. The ancient deforestation and overgrazing of the Mediterranean region is a famous example. And today, a global civilization is ruining the global environment.