At first, I thought the March 1945 Audubon magazine I found tucked inside an old book would only be interesting to look at for its visual content and design:
It has a two-color cover, but the inside is black-ink-only.
I especially liked this spot illustration for the letters page...
...and this ad for a martin colony (I love bird houses!).
But as I paged through it I realized it contained an article called "In Praise of Insects" that is perhaps more relevant today than it was even when it was written:
And so I thought I would type it in and upload it to the interweb for posterity.
In praise of insects…The writing — 17 years before Rachel Carson's Silent Spring was published — is a bit florid and some of the references are dated (yay, tobacco!), but the message is clear: life on earth is a complex web and humans can't wipe out the inconvenient ones without negative effects on other life forms, including humans ourselves.
A protest against their indiscriminate destruction
By Herbert F. Schwarz, photographs by Edwin Way Teale
Since the discovery of its uses as an insecticide only a few years ago, DDT (dichloro-diphenyl-trichloroethane) has become an instrument of transcendent importance in medical entomology. It has solved the louse problem and hence has removed fear of typhus. It has been claimed that it is the most effective weapon against malaria due to its destruction of mosquitoes. It has been applied with good results to other vectors of disease in the insect world. Because of these triumphs, a wider sphere of usefulness is now envisioned for it. Forest and field are to be purged of the pests that infest them, and everything is to be well thereafter.
It is at this point that serious doubts begin to assail one. The very potency of this destructive agent should make for caution in applying it on a broad scale. The insect world is a highly complex on. As yet we know all too little of the hundreds of thousands of species that are spread over the glob and of their interrelations and interdependencies. But we do know that the insects are our allies though sometimes a nuisance and capable of creating economic losses; we are apt to take for granted the helpful activities of our insect friends at the same time that we denounce those which in the course of their activities affect our lives adversely in this way or that.
It seems appropriate, therefore, to make an appraisal of the insects and to emphasize the some of the ways in which they are essential to our well-being and to the ordered harmony of life. There was a time when the value of a bird was measured almost solely by its stomach contents: how many flies it had caught, how many caterpillars it had swallowed. Today we may still pay tribute to the bird for its part in maintaining the balance of nature through its food habits, but surely we no longer limit its value to the purely economic aspects of its activities. Instead we render homage to it as one of the most inspiring things in creation, something that by its flight, song and featured beauty answers an inner craving of our nature. But in proportion as we value birds for the inspirational qualities, we must develop a greater feeling of tolerance toward the insects—even those that may annoy us—on which birds are dependent. For what is to become of that large division of the birds that requires insect food if insect extermination is ever undertaken on a ruthless scale? Even the insects that the average man looks upon as nuisances because they chew up his shade trees and skeletonize its foliage may be valued by some bird as an essential meal. Forests, it would seem, are to be favorite experimental grounds for DDT. A general destruction of silvan insect life might well result in sonless and inanimate woodlands.
Although insects are essential to bird life as we know it, they play a role no less vital in the life of many of the flowering plants. It is upon the bees and to a lesser extent upon the flies—especially the Syrphidae—and the butterflies and moths that these plants are largely dependent for their perpetuation. It has been estimated that there are possibly 20,000 different species of bees. All of these, true to bee development, go through a larval stage, and all all bee larvae are reared on nectar (or honey) and pollen, which is the male germ cell of plants. The adult female bee flies from flower to flower gathering these essentials of life for the coming generation but not all of the pollen grains remain attached to the forager. Some are accidentally shed or rubbed off as the bee explores the recesses of the flower. If they drop opportunely on a female flower of the same species from which the pollen grains were gathered, fertilization is assured and the possibility of reproducing itself is offered to the plant.
One cannot overestimate the tremendous importance of this service performed by the bees, not only as it affects the plant but more importantly as it bears indirectly on man and his very existence. True, certain plants are wind-pollinated, including some of those, like wheat, that provide the staff of life. Nevertheless, the vast majority of our fruits and of our vegetables require the agency of insects in order to develop, and without this aid we should lack an almost unthinkable number of the essentials of existence.
All our garden products with the exception of corn are pollinated by insects. The coffee, tea or cocoa that we may consume at various meals in the course of the day are made possible through the cooperation of our hexapod friends. The grapefruit or baked apple we enjoy at breakfast, the cherries, plums, pears, and other fruits served at lunch and dinner, we owe to the same helpful agencies. Orange juice, lemonade, wine, cider (and its derivative vinegar), the ginger of ginger ale, the hops of beer–all of these beverages or ingredients of beverages and many others we owe to the activity of insects. The spices of the East would not be available without their services as pollinators.
It is not food alone that is assured to use by our insect helpers. Their activities in our interest extend into other spheres. There are moments when a cigarette is more desired than nutriment; a pipe is the companion and consolation of many a perennial puffer; and a good cigar often is the last enjoyment of the day. For all of these pleasant indulgences we are indebted to the pollen-carrying insects, which visit the tobacco flowers, cause the plant to set seed, and thus assure next year’s plants with their fresh crop of leaves.
Although we might conceivably get on without tobacco—at one time the Old World, at least, actually did—it is almost unthinkable that we could find adequate substitutes for cotton and wool. Yet the cotton plant is directly dependent on the action of insects for its pollination and, as for wool, that too, while it is the produce of the sheep, it is also linked indirectly with insect activity. For sheep—and the same might be said for cattle—red clover is a very nutritious diet. In the pollination of red clover bumble-bees are at least the chief agents.
Some regions of the earth—among them New Zealand and Australia—have no indigenous bumble-bees. For a long succession of years sheep-raisers in New Zealand had to import annually all their red clover seed in order to assure proper pasturage for their animals. Then bumble-bees were introduced and from that point on the New Zealand clover was self-perpetuating, thanks to the ministrations of the bees. To Australia bumble-bees were also transported, but their establishment on that continent has been less successful than in New Zealand. We who number bumble-bees among our native avifauna should safeguard these valuable allies, to which we are indirectly indebted not only for world but also for mutton.
Purple vetch is another flower that is visited almost exclusively by bumble-bees. Such partnerships between a given insect and a particular flower or between a given group of insects and a genus of plants occur elsewhere in nature. Sometimes the degree of specialization that each of the partners has attained in the interests of the partnership is such that the destruction of one partner involves the doom of the other. In view of their interrelations, an undiscriminating attack on the insect world would have profound repercussions upon the world of plants.
One might write at length with zest and enthusiasm regarding the products that we owe to insects. For centuries, silk, the output of the silk warm, was the world’s choicest raiment, and, notwithstanding the fact that nylon and rayon are disputing its preeminence, silk culture is spreading. Several of our Latin American neighbors are engaged in sericulture and in the Belgian Congo, too, this activity has taken root. More astonishing still, a beginning has been made of silk-raising in the environment of New York.
The value of honey is universally recognized. It was relished by the cave men of Europe. It was sold in the markets of Egypt. Apiculture has today spread over much of the world. Beeswax has been an invaluable product, too, and over the centuries has found innumerable uses.
Before the discovery of aniline dyes, cochineal, obtained from a Mexican insect, was a favorite coloring agent. The cochineal insect, like the more valuable Indian insect that produces shellac, belongs to the order Coccoidea that includes many insects the beneficial uses of which we may not yet have discovered. This should be remembered by way of offset when we denounce such Coccoidea as the pernicious San Jose and oyster scales.
Many other products should find mention in a panegyric of the insects but consideration of space limits me to the few examples cited, for it is high time that praise be bestowed on those insects to which we are indebted for keeping within proper bounds other insects that might otherwise become excessively destructive. The majority of the insects that make a nuisance of themselves are exotics that have reached our shores unaccompanied by the insects that prey upon them or that parasitize them in their country of origin. Hence they run rampant to the destruction of our crops and our foliage. The only reason that the same thing does not occurring in the case of our native insect fauna is that fauna is kept in check by other native insects that feed on them.
The insects that as predators or as parasites attack other insects are often highly selective of their pretty, confining themselves to certain species or grumps of species. Hence the serious reduction in the numbers of a given insect that exercises a control over the population of its prey may result in the inordinate abundance of the prey, which thereby has been liberated from the persecution to which it is normally subjected.
Due to the potency of DDT and its abiding toxic quality it is bound to deal destruction to those insects on which man is today dependent for his well-being as well as to those that affect him adversely. As yet it would seem that most of the experiments testing the destructiveness of DDT have been confined to the so-called harmful insects. Yet even among these the results have not been uniform, some species within a single family showing more resistance to the toxic qualities than others. It is fair to assume that many disparities would reveal themselves if the the experiments were applied more widely, and that instances would come to hand where the insects we seek to control are more resistant to the poison than the insects that prey upon them.
The difference in susceptibility to the poison on the part of different organisms is, however, only one element of concern. It must be remembered that, while many insects lead an exposed existence, others spend at least their larval life secreted in the earth or in the trunks and branches of trees. Thus inequalities are likely to assert themselves in the mortality of this species or that true to the different degree of security enjoyed.
What about the aquatic insects? It is claimed that one pound of DDT in a 5% solution of Diesel or fuel oil is sufficient for the destruction of the larval stages of mosquitoes present in a stretch of 5 acres of water. That is a measure of the tremendous potency of this insecticide. But what about the insect larvae other than those of mosquitoes that share this water habitat? What about the May flies, for instance, and the dragonflies that are both important in man’s economy? What about the fish that feed on aquatic insects and what about the fishermen whose avocation depends upon the presence and well-being of those fish?
The account here given is not intended as a challenge to the legitimate uses of DDT but is an expression of hope that DDT may be applied with the discreet caution that should attend the employment of anything so devastatingly effective as this chemical is claimed to be. The power of life and death over fauna as inclusive and significant as that represented by insects calls for restrain lest that which from time immemorial has established its place in the scheme of things be put in jeopardy or be injured beyond redress.
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