Is Man Winning the War Against Insects?
WAR! The very mention of the word stirs up the senses. And to think of a continuous, nonending war can be very distressing indeed. Yet, we have been told that just such a war is being fought. The issue: The very existence of either side—for it is fought over the precious food supply both sides need for sustenance. The combatants: man versus the insects.
Some have viewed it as a war of extinction—that it is either “them” or “us.” But that is really not the case. Without insects this would be a sorry world, indeed, for man needs bees, certain flies, butterflies, wasps, beetles, ants and moths to pollinate his plants. Some crops rely on them. There would be no apples, grapes or clover, and far less of other fruits and vegetables were it not for insects. Insects supply man with honey, wax, silk, dye and shellac. Many songbirds that delight mankind feed almost entirely on insects. A number of insects are most useful in controlling weeds. Insects also perform needed tasks as scavengers, contributing to soil aeration and fertility, while disposing of wastes. And in many places people depend on them for food. The Mosaic Law specified some insects as acceptable for human consumption, and John the Baptist derived his sustenance from them while in the wilderness. (Leviticus 11:22; Matthew 3:4) Yet from within their ranks come those who, from man’s viewpoint, war with man over his food.
Although insects may be very small, indeed, in comparison to man, they can muster impressive forces. Collectively they outnumber man by about 250 million to 1. They also outweigh man by the ratio of 12 to 1. According to one estimate, there are 800,000 different insect species on earth today. The total number of individual insects is astronomical—far beyond our comprehension. Fortunately, it is only a small number of earth’s insect population—less than 1 percent—that are considered harmful to man and are warring with him over his food crops, woodlands and materials.
Their battle tactics would be the envy of any field marshal. Masters of the element of surprise, they invade suddenly and in force, as if overnight. They set up battle lines right in the midst of the food supplies that man wants to protect, forcing him into the quandary of how to destroy the one while preserving the other. Their underground and camouflage tactics, together with their size, enable them to strike undetected while inflicting heavy damage.
They breed prodigiously. A new generation of fighters, all fully trained and battle ready, can be produced in as little as a week. Infants fight as capably as adults, males and females alike join in the fray. Some divisions infiltrate and entrench themselves in man’s own home, running forays to harass and contaminate. Others are experts in germ warfare, spreading the dread diseases of malaria, yellow fever, bubonic plague and sleeping sickness, to name a few. And although poisoned by man, they can adapt and even live in such an environment. Thus the war has continued down through the ages.
At first, all man could do was wait out the attacks and hope for better times to come. Pharaoh and the ancient Egyptians simply had to endure the plagues of gnats, gadflies and locusts that God brought upon them. And what devastation they must have wrought, for an adult desert locust can easily eat vegetation equivalent to its own weight each day! One swarm covered 400 square miles and contained an estimated 40 billion locusts. It alone could consume enough food each day to feed 400,000 people for a year! And yet, breeding as profusely as they do, why have insects as yet not won the war?
The Inner War
Fortunately for man, a concurrent and unceasing war is also going on among the insects. If this were not the case, man might not have had any hope at all. One common aphid, for example, has the capability of producing 6,000 million others in its short life span. If all aphids did so, without restraints, it would not be long before these plant lice would destroy all vegetation on earth.
But nature maintains a balance. There are insect predators, parasites and diseases, not to mention other natural and climatic factors that serve to keep the insect population in check. Some plants, too, have natural defense mechanisms. Red oak trees defoliated by hungry gypsy moths fight back by chemical changes in the replacement leaves that make them indigestible. In the case of the locust plague in Pharaoh’s day, Jehovah God caused a stiff wind to drive the locusts away into the Red Sea.—Exodus 10:12-19.
Man Works Toward Self-Defeat
It was man himself who upset the balance in nature and escalated the war. Abandoning the sound agricultural practices of crop diversity and rotation that kept pests from getting firmly entrenched and that maintained plant resistance to pests and diseases, he resorted instead to massive monocultures—single-crop farming over a large area. In search of higher and more cosmetically attractive yields, he bred out much of the plants’ natural resistance to pests. New crops, along with new insects, were introduced in countries where they had never been grown before but without their natural enemies to control them. Insects formerly kept in check suddenly had conditions that allowed them to multiply at alarming rates. The battle was getting out of control and the insects were winning!
Man quickly went in search of new weaponry. Relief came with a battery of synthetic pesticides. These broad-spectrum chemical killers, beginning with DDT, destroyed insects at prodigious rates. Man thought he would win the war at last. Crop yields increased dramatically. Insect-borne diseases started to disappear. Victory appeared in sight and was proclaimed as imminent.
But in his war of utter extermination, man killed foe and friend alike. As one scientist put it: “When we kill a pest’s natural enemies, we inherit their work.” Suddenly, free from their natural enemies, they proliferated at alarming rates. Other insects, previously unimportant, joined their ranks as major pests. More potent chemicals were used, but again the insects regrouped and counterattacked. Some farmers were found to be spraying their crops as much as 50 times in a single growing season and still losing up to half the crop.
Not only were the chemicals failing to eradicate the insects but the insects were becoming immune to the chemicals, and some even thrived on them. So effective had their resistance to pesticides become that scientists were able to feed colonies of houseflies large doses of DDT without apparent adverse effects. Moreover, the birds, so useful in controlling insects, were being killed by eating the poisoned insects, seeds and fruits.
And these poisons rapidly moved up the food chain, poisoning fish and keeping birds from reproducing, upsetting the ecology and showing up in increasing amounts in man’s own food and water. Man’s chemical weapons were backfiring. “Superbugs,” some four hundred insect species resistant to insecticides, became the shock troops for renewed insect invasions and the increased spread of diseases to man. Insects were again winning the war.
Man’s New War Strategy
Man had to look quickly for a second line of defense. He began to learn the importance of the battle cry: “Know thine enemy.” Difficult, indeed, considering their variety, size and habits, but better intelligence was now absolutely necessary to turn the tide in the war. He had to learn the pests’ genetics, biology, ecology and behavior. He needed to dig deep to learn their feeding and reproductive habits, how their reproductive cycles meshed with crop maturity and the life cycles of their insect enemies, and how these were affected by weather and planting times. He even had to learn precisely just how much one insect ate, to determine how many could be tolerated before costly damage was done. He had to discover when they did the most damage and how to make them vulnerable. Man had to restore the balance in nature. He realized he could not kill indiscriminately, for he depended on the beneficial insects for his own survival.
Man also discovered that maintaining small populations of the crop pests may even be the most effective way to reduce crop losses, thus ensuring a food supply for their natural enemies and keeping them from dying out. He learned that insect-free agriculture was neither wise nor attainable, for man can win the battle but lose the war.
Coexistence and control, rather than extermination, became man’s new war strategy. A system called IPM (Integrated Pest Management) was devised. Early warning systems were set up to predict or detect a pest’s presence long before it could cause crop damage, giving the farmer a chance to take the offensive before the enemy appeared in invasion force. He then could use a variety of biological controls: natural predators and parasites, pest diseases, sterilized males to lower birth rates.
Involved also were the farmers’ returning to crop rotation and diversity, cultivation practices that discourage pest infiltration and reproduction, changing planting schedules, planting crops that are more insect resistant, and even using decoy crops to divert the enemy’s fire from the main crop. Pesticides, the atom bombs of man’s warfare, could then be used as a last resort—but only when needed and in careful and limited applications. Farmers using these methods have reported good yields, while drastically reducing their costly use of fertilizers and insecticides.
How Is the War Going Now?
But the war is far from being won. Insect pests still consume 40 percent of the world’s food crops. “We’ll never actually win,” says entomologist David Pimentel, “because insects are so pervasive around the world that it’s absolutely impossible to keep them out of crops and food.” Much has yet to be done to control the tobacco budworm, African armyworm, boll weevil, Japanese beetle, whitefly, green peach aphid, gypsy moth, red fire ant, spruce budworm, cockroach, termite, housefly and mosquito—to name just a few of the agricultural, environmental and household pests that still plague mankind.
Scientists are still experimenting with new weaponry: hormones that interfere with normal growth, pheromones (insect sex perfumes) that disrupt mating, pathogens that cause disease, antifeedants that eliminate an insect’s desire to eat. But much testing has to be done to ensure their effectiveness and harmlessness to man. Meanwhile, there is still the widespread use of chemical pesticides, as many opt for the quick kill over slower biological controls. But scientists fear that, due to buildup of insect resistance, their chemical arsenal may soon be exhausted.
The final solution lies, not with man, but in God’s intervention to establish a truce and bring all things back into perfect balance. Soon, in God’s righteous New Order, man will no longer even think of war.
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PESTICIDES