For as long as the Earth has existed, living beings have had little influence over its processes and development, until the 20th century, when everything changed. Since the 1940’s the human ability to affect the entire planet and its environment became highly dangerous. They began to pollute the air, soil and water, and the damage they caused was mostly irreparable. The radiation produced by the manipulation of the atom, and the effect of synthetic substances which are not found in nature, drastically altered the delicate balance that would take generations to restore.
Every year, 500 new chemicals are added to the list. Since 1945, over 200 extremely harmful compounds have been created to kill weeds, destroy pests, and exterminate insects. The justification for these practices was, and still is, that these chemical compounds are necessary to protect agricultural production, when in reality the United States is dealing with a problem of overproduction. In 1962, US taxpayers paid over a billion dollars in taxes for the transport and storage of agricultural surpluses.
There is another aspect of this shift to consider: the diffusion of insects in the world is changing. All the way back in the cretaceous period, (some 100 million years ago) when the seas separated the continents, biological islands were formed, and on each one different species evolved. When some land masses were joined together again, about 15 million years ago, insects began to migrate to other territories, and not only is this movement still in progress, it is also given a significant boost by the migration, movements, and actions of humans. The importation of plants is the primary agent in the modern spread of species, since animals have almost invariably gone along with the plants, with quarantine being a somewhat ineffective innovation.