Rachel Carson,
Silent Spring,
.gif)
(ISBN 0-395-45390-9)
Rachel Carson, |
Silent Spring,
|
|
|---|---|---|
|
|
|
|
| (Boston: | ||
| Houghton Mifflin, 1962. | ||
|
(ISBN 0-395-45390-9) |
|
The importance of Rachel Carson's works?
William O. Douglas, Supreme Court Justice said:
"The most important chronicle of this century for the human race."
1. Interpretation of nature's value to humankind
2. Visualization of the ecological relations among living things, or web of life
3. Reconcile the picture of reality (biocides) with the words (pest control) or allegedly "safe" forms of insecticides.
Chapter 16. The Rumblings of an Avalanche
IF DARWIN were alive today the insect world would delight and astound him with its impressive verification of his theories of the survival of the fittest. Under the stress of intensive chemical spraying the weaker members of the insect populations are being weeded out. Now, in many areas and among many species only the strong and fit remain to defy our efforts to control them. Nearly half a century ago, a professor of entomology at Washington State College, A. L. Melander, asked the now purely rhetorical question, ‘Can insects become resistant to sprays?’ If the answer seemed to Melander unclear, or slow in coming, that was only because he asked his question too soon—in 1914 instead of 40 years later.(p. 137)
"To have risked so much in our efforts to mold nature to our satisfaction and yet have failed in achieving our goal would indeed be the final irony . . . . The truth is, . . . that nature is not so easily molded and that the insects are finding ways to circumvent our chemical attacks on them." (245)
"We stand now where two roads diverge . . . . Our only chance to reach a destination that assures the preservation of our earth." (276)
"The 'control of nature' is a phrase conceived in arrogance, . . . when it was supposed that nature exists for the convenience of man . . . . It is our alarming misfortune that so primitive a science has armed itself with the most modern and terrible weapons, and that in turning them against the insects it has also turned them against the earth." (297)
5. How Silent Spring is significant for us:
A. historically -- ecological revolt 1949-1969B. scientifically -- Darwin's natural selection
C. personally -- we are nature hiding from ourselves
6. Reconciliation of competing values:
A. the middle landscape is unraveling
B. the organic revolt (1850-1900) as a parallel
C. Conservation needs to be ecologically redefined
Chapter 16 | speed of growing resistance | malaria | resistance appeared | enzymes | Chapter 17
Chapter 16. The Rumblings of an Avalanche
In the pre-D-D-T era, inorganic chemicals, applied on a scale that today would seem extraordinarily modest, produced here and there strains of insects that could survive chemical spraying or dusting.
But it was the advent of DDT and all its many relatives that ushered in the true Age of Resistance.
Only those concerned with disease-carrying insects seem by now to have been thoroughly aroused to the alarming nature of the situation; the agriculturists still for the most part blithely put their faith in the development of new and ever more toxic chemicals, although the present difficulties have been born of just such specious reasoning.
A distinguished British student of animal populations, Dr. Charles Elton, has said, ‘We are hearing the early rumblings of what may become an avalanche in strength.’
pp. 137-138.
Although insect resistance is a matter of concern in agriculture and forestry, it is in the field of public health that the most serious apprehensions have been felt. The relation between various insects and many diseases of man is an ancient one.
138.
No responsible person contends that insect-borne disease should be ignored. The question that has now urgently presented itself is whether it is either wise or responsible to attack the problem by methods that are rapidly making it worse.
A distinguished Canadian entomologist, Dr. A. W. A. Brown, was engaged by the World Health Organization to make a comprehensive survey of the resistance problem. In the resulting monograph, published in 1958, Dr. Brown has this to say: ‘Barely decade after the introduction of the potent synthetic insecticides in public health programs,the main technical problem is the development of resistance to them by the insects they formerly controlled.’
Malaria programs are threatened by resistance among mosquitoes. The oriental rat flea, the principal vector of plague, has recently demonstrated resistance to DDT, a most serious development.
p. 138-139.
As rapidly as new chemicals were brought into use, resistance developed. By the end of 1951, DDT, methoxychlor, chlordane, heptachlor, and benzene hexachloride had joined the list of chemicals no longer effective."
p. 139.
Resistance to insecticides by mosquitoes of the anophelene group has surged upward at an astounding rate, being created by the thoroughness of the very house spraying programs designed to eliminate malaria. In 1956, only 5 species of these mosquitoes displayed resistance; by early 1960 the number had risen from 5 to 28!
P. 140.
Less serious in terms of human health, but vexatious as man measures economic values, is the fact that salt-marsh mosquitoes in Florida also are showing resistance. Although these are not vectors of disease, their presence in bloodthirsty swarms had rendered large areas of coastal Florida uninhabitable until control—of an uneasy and temporary nature—was established. But this was quickly lost.
p. 140.
They seem immune to DDT or chlordane or most of our modern sprays. It used to be very unusual to have ticks in New York City, but now they’re all over here and on Long Island, in Westchester and on up into Connecticut.
p. 141.
Dr. Brown has pointed out that we are traveling ‘a one-way street’. No one knows how long the street is. If the dead end is reached before control of disease-carrying insects is achieved, our situation will indeed be critical.
The first cases of DDT resistance among agricultural insects appeared in the United States in 1951, about six years after its first use.
The chemical industry is perhaps understandably loath to face up to the unpleasant fact of resistance. Even in 1959, with more than 100 major insect species showing definite resistance to chemicals, one of the leading journals in the field of agricultural chemistry spoke of ‘real or imagined’ insect resistance.
Darwin himself could scarcely have found a better example of the operation of natural selection than is provided by the way the mechanism of resistance operates. Out of an original population, the members of which vary greatly in qualities of structure, behavior, or physiology, it is the ‘tough’ insects that survive chemical attack.
p. 141.
Nevertheless, the quality of resistance does not necessarily depend on physical structure. DDT-resistant flies possess an enzyme that allows them to detoxify the insecticide to the less toxic chemical DDE.
p. 142.
'If insects can become resistant to chemicals, could human beings do the same thing?’ Theoretically they could; but since this would take hundreds or even thousands of years, the comfort to those living now is slight. Resistance is not something that develops in an individual. If he possesses at birth some qualities that make him less susceptible than others to poisons he is more likely to survive and produce children. Resistance, therefore, is something that develops in a population after time measured in several or many generations. Human populations reproduce at the rate of roughly three generations per century, but new insect generations arise in a matter of days or weeks.
p. 142.
We need a more high-minded orientation and a deeper insight, which I miss in many researchers. Life is a miracle beyond our comprehension, and we should reverence it even where we have to struggle against it... The resort to weapons such as insecticides to control it is a proof of insufficient knowledge and of an incapacity so to guide the processes of nature that brute force becomes unnecessary.
p. 143.
Chapter 16 | speed of growing resistance | malaria | resistance appeared | enzymes | Chapter 17
Chapter 17. The Other Road
WE STAND NOW where two roads diverge. But unlike the roads in Robert Frost’'s familiar poem, they are not equally fair. The road we have long been traveling is deceptively easy, a smooth super highway on which we progress with great speed, but at its end lies disaster. The other fork of the road—the one ‘less traveled by’—offers our last, our only chance to reach a destination that assures the preservation of our earth144.
‘Any science may be likened to a river,’ says a Johns Hopkins biologist, Professor Carl P. Swanson. ‘It has its obscure and unpretentious beginning; its quiet stretches as well as its rapids; its periods of drought as well as of fullness. It gathers momentum with the work of many investigators and as it is fed by other streams of thought; it is deepened and broadened by the concepts and generalizations that are gradually evolved.’So it is with the science of biological control in its modern sense.
p. 144.
As we have seen in, the mission was crowned with spectacular success, and in the century that followed the world has been combed for natural enemies to control the insects that have come uninvited to our shores. In all, about 100 species of imported predators and parasites have become established. Besides the vedalia beetles brought in by Koebele, other importations have been highly successful. A wasp imported from Japan established complete control of an insect attacking eastern apple orchards. Several natural enemies of the spotted alfalfa aphid, an accidental import from the Middle East, are credited with saving the California alfalfa industry. Parasites and predators of the gypsy moth achieved good control, as did the Tiphia wasp against the Japanese beetle. Biological control of scales and mealy bugs is estimated to save California several millions of dollars a year—indeed, one of the leading entomologists of that state, Dr. Paul DeBach, has estimated that for an investment of $4,000,000 in biological control work California has received a return of $100,000,000.
The predator and the preyed upon exist not alone, but as part of a vast web of life, all of which needs to be taken into account. Perhaps the opportunities for the more conventional types of biological control are greatest in the forests. The farmlands of modern agriculture are highly artificial, unlike anything nature ever conceived. But the forests are a different world, much closer to natural environments.
p. 151.
The current vogue for poisons has failed utterly to take into account these most fundamental considerations. As crude a weapon as the cave man’s club, the chemical barrage has been hurled against the fabric of life—a fabric on the one hand delicate and destructible, on the other miraculously tough and resilient, and capable of striking back in unexpected ways.
These extraordinary capacities of life have been ignored by the practitioners of chemical control who have brought to their task no ‘high-minded orientation’, no humility before the vast forces with which they tamper. The ‘control of nature’ is a phrase conceived in arrogance, born of the Neanderthal age of biology and philosophy, when it was supposed that nature exists for the convenience of man. The concepts and practices of applied entomology for the most part date from that Stone Age of science. It is our alarming misfortune that so primitive a science has armed itself with the most modern and terrible weapons, and that in turning them against the insects it has also turned them against the earth.
pp. 154-55.
Chapter 16 | speed of growing resistance | malaria | resistance appeared | enzymes | Chapter 17
Words as indicative of meaning, etymology, and intentions when writing.
Marshes of the Ocean Shore Terms | Glossary | Word webs | Basic vocabulary | Advanced Vocabulary | Antonyms | Synonyms
Writing | Interviews | Free Writing
Home | Site Map | Quick Look
