Insects—Friends or Foes?
By “Awake!” correspondent in Peru
THE audience was paying rapt attention to the speaker, oblivious of the tropical heat and humidity that permeated the room. Suddenly an intruder with huge iridescent blue-green wings burst through a window! To the alarm of one woman, a North American unfamiliar with the local inhabitants, it headed her way!
Her first reaction was to throw her notebook at it. When this did not discourage its interest in her, she turned to her husband for help. The situation returned to normal when it was discovered that the intruder was a large but harmless grasshopper.
How would you have reacted? No doubt about it, insects can prompt a very dramatic reaction in some people. But is such a response always warranted? Or to put it another way: Are insects friends or foes? ‘Insects are such pests!’ you may say. ‘They bite. They sting. They ruin picnics. Who needs them?’
Yet, these little creatures play a vital role in the life systems here on earth. Perhaps getting better acquainted with the insect world would allay the fears of many.
Biggest Family on Earth
There are almost a million described species of insects already identified by man—more species than of all other animals combined. That means that if you learned the names of a hundred species every day, it would take you more than 27 years to learn the names of all the known species! But some sources indicate that there are yet millions of unidentified insect species.
Strictly speaking, not every little creature that crawls is an insect. How can you tell an insect? It’s very simple. Its body is divided into three parts (head, thorax and abdomen). It has one pair of antennae. Now, count its legs. If there are six, it’s an insect. If there are more or less than six, it’s not. For example, spiders, with four pairs of walking legs, strictly speaking are not insects but belong to the class known as arachnids.
How do insects contribute to the web of life here on earth? Well, man already appreciates the role of insects such as bees and butterflies in plant pollination. And ants? Why, in just one acre (0.4 ha) these tiny insects move tons of soil in a year, loosening and aerating it! Roaches and beetles feed on decaying matter; their own excreta nourish the soil. A number of insects serve as food for man, such as locusts, crickets, termites, ants and large beetles. From insects man obtains honey, beeswax, silk, shellac, dye and substances with medicinal value.
Strange as it may sound, insects even contribute to man’s pleasure. Perhaps you have enjoyed the chirp of a cricket, the murmur of busy bees on a warm summer afternoon, or the night dance of fireflies. Why, in the Amazon jungle area children can be observed playing with large beetles tied to a string!
True, some insects are terrible pests or disease-carriers. However, most really are not foes. Rather, they destroy weeds or just provide food for fish, birds, reptiles, mammals, and other insects. Let’s take a closer look at a few of them.
The Army Ants
Have you ever observed the irresistible march of aggressive ants? The march of hundreds of thousands of army ants, or driver ants, is one of the most awesome spectacles in the insect world. Any object in their path is overwhelmed by these militant columns; a tethered horse or a lethargic python can be reduced to mere bones in a few hours! Unlike other species of ants, the tropical army ant does not make a nest but marches, or advances, almost constantly, in swarms that are sometimes 16 yards (14.6 m) wide.
Scouting parties of soldiers with large heads and awesome scythelike jaws lead the way, scenting their path chemically. The main body of ants follows their scented trail. Traveling over 220 yards (200 m) in a day, moving only in daylight, this expedition is in action for about two weeks in its voracious and frantic search for food, especially to feed the ant larvae that are carried along. Then comes a pause in the advance as the queen lays 100,000 to 300,000 eggs; after about 20 days when these eggs become hungry larvae, the migration begins again. And to think that this fearsome army of soldiers and workers in all their frenzied activity are blind!
The army ant is the ‘new broom that sweeps clean,’ clearing the path of all grubs, larvae or any other creature caught unawares. Why, some natives are glad to have them pass through their rustic homes just to get a thorough housecleaning!
Large and Lovely
Not all insects are ugly. Some are quite beautiful—such as butterflies. Wouldn’t you agree? Breathtaking indeed is the sight of colorful and varied tropical butterflies, some as big as birds, who in their size and brilliance are visible hundreds of yards (meters) away. Especially admired are the morpho butterflies; their iridescent blue coloring has so fascinated men that these butterflies have been mounted in picture frames, providing a color background that defies the artist’s brush.
How big are cockroaches in your part of the world? Well, how do they compare in size to the South American Blaberus giganteus? With a length of about two inches (5 cm), it is one of the world’s largest! And what about moths in your part of the world? How would you feel if one with a wingspan of about one foot (30 cm) flew by you? That is the size of the owlet moth of South America. The world’s largest ant, Dinoponera gigantea, over one inch (2.5 cm) long, lives in the Brazilian jungle. Have you ever seen an ant that big?
Chigoe—A Tube Without Wings
There are about 1,400 different kinds of fleas in the world. Have you ever suffered the discomfort of making their acquaintance? No one likes a flea bite, but since most fleas do not live on their host, but just feed on him, the presence of a flea can be a good reminder to do a little more thorough housecleaning or to give your pet more careful attention.
Along the coast of Peru, and in other tropical areas of Central and South America, lives the most irksome member of the flea family—the chigoe. In Peru the chigoe, or chigger, is known as a pique. The impregnated females attach themselves to the feet of livestock, such as cattle or swine—or people—and penetrate the soft skin between the toes, under the toenails or any other spot where they can get a “toehold.”
The chigger buries herself under the skin with the tip of her abdomen remaining outside. Her breathing apparatus, anus and ovipositor (organ for depositing eggs) thus are outside her victim. Her abdomen then swells to the size of a small pea in a few days and will soon drop several thousand eggs on the ground. When the chigger finally dies she remains in the blister she has formed on her host; this can cause inflammation and, if neglected, a serious infection, tetanus or, worse yet, amputation of a toe! This, however, is a rare happening since the insect’s presence is soon felt and the distraught victim prefers to endure the pain of gouging out the entire blister, with its sliver-shaped culprit.
Of the almost one million species of insects already identified and named by man, how many do you know? Of the ones you know, can you explain their characteristics? The thought of thoroughly searching out this knowledge staggers the mind. But what a fascinating challenge!
So the next time you turn over a stone, slice a shovel through the soil or hear a hum in the breeze, don’t recoil at a potential foe—take a closer look at a possible friend. In doing so, you will no doubt find beauty, purpose, perhaps some amusement and enough wisdom to justify some study and contemplation.
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Columns of army ants overwhelm anything in their path
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Some butterflies are as big as birds
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South American cockroach (actual size)