It is estimated that about 90% of all species that have ever lived have disappeared. This is
natural, since the extinctions have occurred through natural processes, with the fitter always
surviving. It has not been until after humans learned to hunt animals that the extinction rate began
to soar. Now a days people are destroying forests, polluting the air and water, and hunting, that
50-100 species are going extinct everyday. If we keep on destroying the earth as we are doing so,
in a few decades millions of species will go extinct, perhaps 50% of the present number. The
majority of extinctions are occurring among the invertebrates, especially the insects. The
extinction of plants is also important, since about 20-40 animals depend on each plant. When a
species of plants dies, at least one, if not more animals die. The destruction of tropical forests is
another major problem. About 70-95% of all species live in tropical forests. If we keep on killing
all the exotic species, the only animals that will survive are animals like rats, and our society will
become a “pest-dominated society.”