Ecology is a word that is often used and less often understood. Ecology deals with the relationships of living things (organisms), including man, to their surroundings. It is a young science, dealing with a broad and complex subject, and has yet to reach the sophistication or predictive ability of anatomy or physics.
However, some conclusions seem clear. Among the most important are these:
1. Resources are limited. Therefore, they are passed from organism to organism. For example, the energy content (calories) of plant food matter is passed on to other living things, such as from grass to a cow to a man to bacteria, maggots, and fungi. Another way of putting this is to say that we are traveling together on “spaceship earth,” or that the earth is a closed system.
2. All organisms are absolutely dependent on other organisms. This follows naturally from conclusion 1. Most animals depend directly on green plants for food. Green plants depend on animals to pollinate them, disperse their seeds, and eliminate competitors. Animals and green plants depend on fungi and bacteria for the recycling of important materials. This interdependence is expressed in terms such as community, a word used to designate all the organisms coexisting in a particular place.
3. A community repairs itself slowly if damaged. For example, forests will reappear in abandoned fields in most parts of the United States, but only after many years.
4. Pollution simplifies communities. A pollutant is abnormal by definition. Many organisms (man, rats, and most weeds are exceptions) will survive only under a narrow range of conditions normal to them. Spilling oil, changing the temperature, or altering some other condition usually eliminates some species from ...1