Damian's first task as Robin was to rescue Tim. As of the "New 52", Damian continued to work with his father, but temporarily gave up being Robin as his mother put a price on his head , and went under the identity of Red Bird. Damian met his end at the hands of Heretic, an aged-clone of Damian working for Leviathan , bravely giving up his life. Batman eventually started a difficult quest to resurrect him, returning Damian to life with Darkseid 's Chaos Shard.
A Batman story from the s featured the young Bruce Wayne assuming the identity of Robin, complete with the original costume, in order to learn the basics of detective work from a famous detective named Harvey Harris. The purpose of the secret identity was to prevent Harris from learning Wayne's true motivation for approaching him, which could have led to the detective attempting to discourage the boy from pursuing his obsession. Post-Crisis, there was one instance in continuity when Bruce Wayne adopted the Robin persona.
In an effort to keep up the illusion of Batman, Bruce had Tim adopt the Batman identity while he is forced to be Robin. By the s, Grayson had become an adult, and was a lawyer and the ambassador to South Africa. He adopted a more Batman-like costume, but still fought crime as Robin.
Although in semi-retirement for a time, he was called back to active duty when he rejoined the Justice Society during the period when he, Power Girl and Star-Spangled Kid , assisted them as The Super Squad. He appeared to have died during the miniseries Crisis on Infinite Earths , in which the DC Multiverse was reduced to one Universe, and this version of Grayson, as well as the Earth-Two Batman, were deemed never to have existed.
The Earth-2 concept was revived and reimagined twice subsequently, following the comic books 52 —7 and Flashpoint In the DC One Million storyline, members of the Justice League of America encounter a variety of heroes from the future, including an rd-century Batman who patrols the prison planet Pluto.
This version of Batman is accompanied by a robotic Robin who contains a transcribed copy of his own personality from before his parents were murdered by Plutonian criminals. This Robin who calls himself "the Toy Wonder" is a member of the Justice Legion T in addition to serving as a deliberate counterbalance to Batman's dark personality. Elseworlds versions of DC characters are ones that exist in alternate timelines or realities that take place in entirely self-contained continuities.
She becomes Robin, and is accepted by the Batman after she saves his life. Unlike the previous Robins, Carrie is not an orphan, but she appears to have rather neglectful parents who are never actually depicted one of them mutters "Didn't we have a kid? It is hinted through their dialogue that they were once activists and possibly hippies during the s, but have since become apathetic stoners. She was the first female Robin and the first Robin with living parents. Crime Syndicate version of Robin on Earth-3, associate of Owlman.
Talon first appeared in Teen Titans vol. In the final issue of 52 , a new Multiverse is revealed, originally consisting of 52 identical realities. Among the parallel realities shown is one designated " Earth-2 ". As a result of Mister Mind "eating" aspects of this reality, it takes on visual aspects similar to the pre-Crisis Earth-2, including Robin among other Justice Society of America characters.
Indeed, in Justice Society of America 20, published in December , Starman explains that during the re-expansion of the DC Multiverse , Earth-2 was reborn "along with everyone on it", including Robin. Following Flashpoint and The New 52 reboot, this Earth is replaced by another reimagining of Earth 2, one where Batman's daughter Helena Wayne served as Robin until an incident five years prior to the relaunch sent her to DC's primary continuity, Earth-0, where she works as Huntress.
The series Earth 2: World's End establishes that Dick Grayson never served as Robin on this Earth, and was instead a reporter who married Barbara Gordon and had a son. During Darkseid 's invasion of Earth 2, Barbara is killed, and Dick is trained in how to fight by Ted Grant and goes on a mission to find his missing son. The first Robin miniseries was printed in following Tim Drake's debut as Robin. The series centered around Tim's continued training and set up villains linked to the character.
With Batman out of town, it was up to Tim and Alfred to end the Joker's latest crime spree. In , the success of the three miniseries led to the ongoing Robin series which ran issues until The title was replaced by a Batman and Robin series following the Battle for the Cowl mini-series, as well as an ongoing Red Robin monthly which continues the story of Tim Drake.
The ongoing Robin series has taken part in a number of crossovers with other comics, especially Batman and related series. These include:. According to Entertainment Weekly in , Robin is one of the "greatest sidekicks". Robin Dick Grayson was portrayed by Douglas Croft and Johnny Duncan , respectively, in the and fifteen chapter Batman serials. Burt Ward played him in the — Batman television series and the related film. The animated series Teen Titans features Robin voiced by Scott Menville as the leader of a team of young heroes; it is hinted in several episodes that this Robin is Dick Grayson.
In another episode, Raven reads Robin's mind and sees a man and a woman falling from a trapeze an event known only to have happened to Grayson and not to any other Robin. In another episode, Starfire travels to the future and discovers that Robin has taken the identity of Nightwing. Menville reprises his role as Robin in Teen Titans Go!
Robin is also seen in the Zeller's commercial, which features the infamous catchphrase, "Well said, Robin! His portrayal is based mainly on Burt Ward's Dick Grayson. Extensive biography on Dick Grayson. Extensive biography on Jason Todd. From Wikipedia, the free encyclopedia. For the Swedish cartoon slacker character, see Robin TV series. For the British children's magazine, see Robin magazine. For other uses, see Boy Wonder disambiguation. Dick Grayson as Robin. Main article: Dick Grayson. Main article: Jason Todd. This article needs additional citations for verification.
Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Main article: Tim Drake. Main article: Stephanie Brown comics. Main article: Damian Wayne. Further information: Alternative versions of Robin. See also: Batman. Main article: Robin Earth-Two. See also: Crisis on Infinite Earths. See also: DC One Million.
Main article: Carrie Kelley. See also: Robin in other media. Batman: The Complete History. Chronicle Books. Retrieved September 14, Retrieved April 6, Retrieved May 12, Entertainment Weekly. New York: Workman Publishing. Court of Owls League of Assassins. Robin Red Robin. Bob Kane Bill Finger Other contributors. Batboat Batcopter Batcycle Batmobile Batplane. In film In video games In amusement parks In children's books. Baby robins cannot fly for the first few days after they leave the nest. Their parents lead them to low shrubs and trees where they first learn to climb and jump. Within a day or two, their wings grow stronger and they begin to take short flights.
Their parents continue to feed them, and within a week or two, they are ready to be on their own. When the young are strong enough, the robins may roost in big groups. Nesting up to three times each year, male robins may watch over the fledging young, while the female incubates the next clutch of eggs. An overview of mason bee basic biology and life cycle, and detailed descriptions of what is needed to start keeping mason bees, including desirable plants, nesting sites and types of nests, and caring for the cocoons over fall and winter. There are many helpful color photos throughout.
Attracting hummingbirds to your garden is easy. You have a good chance of keeping them there if you meet their basic needs for cover, food, water, and space by planting a hummingbird habitat garden. This publication offers information on bats and ways to create roosting habitats for them. It also offers information on native species, natural history, bat houses, simple roosts and more.
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Discusses ways to reduce problems with unwanted wildlife around homes. Covers species from rodents to big game, bears, and cougars. Recommendations include eliminating food and shelter, trapping, hunting, fencing, and hazing. While it can be challenging to find the balance, there is much that we can do to meet our objectives for wildlife while controlling weeds and reducing fuels.
Recent research at OSU can help us make informed decisions about some of the tradeoffs. Oregon has lots of ants. Why aren't there any anteaters or aardvarks? Total fish eaten may now exceed the combined harvest by commercial and recreational fisheries. Natural resource managers need to plan and budget for activities to deal with an invasive animal like the lionfish.
Findings have important implications for understanding how salmon navigate across the wide range of habitats they encounter. Oregon State is the first Pac university to sequence its school mascot. We have experts in family and health, community development, food and agriculture, coastal issues, forestry, programs for young people, and gardening. Home Outdoors and Environments Wildlife How to help robins through the winter in your yard and garden.
Story Source Nancy Allen. Presentation Shared habitat: How we can unpack potential wildlife conflicts Presentation about avoiding conflicts with wildlife in the garden. By Dana Sanchez,. OSU Extension Catalog Nurturing Mason Bees in Your Backyard in Western Oregon An overview of mason bee basic biology and life cycle, and detailed descriptions of what is needed to start keeping mason bees, including desirable plants, nesting sites and types of nests, and caring for the cocoons over fall and winter. By Ramesh Sagili, Brooke Edmunds. Living with Nuisance Wildlife. By Brian Tuck.
Balancing weed control, fuels reduction, and wildlife. So it is that the activities of the insect predators and parasites are little known. Perhaps we may have noticed an odd-shaped insect of ferocious mien on a bush in the garden and been dimly aware that it was a praying mantis, which lives at the expense of other insects. But we see with an understanding eye only if we have walked in the garden at night and, here and there, with the aid of a flashlight, have glimpsed the mantis stealthily creeping up on its prey.
Then we sense something of the drama of hunter and hunted. Then we begin to feel something of that relentless force by which nature controls her own. The predators are of many kinds. Some are quick, and, with the speed of swallows, snatch their prey from the air. Others plod methodically along a stem, plucking off and devouring sedentary insects, like the aphids. The yellow jacket captures soft-bodied insects and feeds the juices to its young. The mud-dauber wasp builds a columned nest of mud under the eaves of houses and stocks it with insects on which its young will feed.
The horse-guard wasp hovers above herds of grazing cattle, destroying the blood-sucking flies that torment them. The loudly buzzing syrphus fly, often mistaken for a bee, lays its eggs on the leaves of aphis-infested plants; the larvae, when they hatch, consume immense numbers of aphids. Ladybugs, or lady beetles, are among the most effective destroyers of aphids, and of scale insects and other plant-eating insects as well. Literally hundreds of aphids are consumed by a single ladybug to stoke the fires of energy that she requires to produce a single batch of eggs. Even more extraordinary in their habits are the parasitic insects.
These do not kill their hosts outright. Instead, they utilize them for the nurture of their young. Some deposit their eggs within the larvae or the eggs of their prey, so that their own developing young can consume the host. Others attach their eggs to a caterpillar by means of a sticky solution; on hatching, the larval parasite bores through the skin of the host. Still others, led by an instinct akin to foresight, merely lay their eggs on a leaf, so that a browsing caterpillar will eat them.
Everywhere, in field and hedgerow and garden and forest, the insect predators and parasites are at work. Here, above a pond, the dragonflies dart, and the sun strikes fire from their wings. So their ancestors sped through the swamps where huge reptiles lived.
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Now, as in those ancient times, the sharp-eyed dragonflies capture mosquitoes in the air, scooping them in with basket-shaped legs. In the waters below, their young, the dragonfly nymphs, or naiads, prey on the aquatic stages of mosquitoes and other insects. And there, almost invisible against a leaf, is the lacewing, with gauzy green wings and golden eyes, shy and secretive, descendant of a race that lived in Permian times.
The adult lacewing feeds mostly on plant nectars and the honeydew of aphids, and in time she lays her eggs, each on the end of a long stalk, which she secures to a leaf. From these emerge her children—strange, bristled larvae called aphis lions, which live by preying on aphids, scale insects, or mites, capturing them and sucking them dry of fluid.
Each may consume several hundred aphids before the ceaseless turning of the cycle of its life brings the time when it will spin a white silken cocoon in which to pass the pupal stage. And there are many wasps and flies whose very existence depends on the destruction of the eggs or larvae of other insects. Some of the egg parasites are exceedingly minute, yet by their numbers and their great activity they hold down the abundance of many crop-destroying species. There is, for example, a tiny wasp of the genus Trichogramma, whose fragile body may be smaller than the eggs of her prey.
She flies tirelessly through the cotton fields, seeking out the eggs of the bollworm and the leafworm, or through orchards, to find the eggs of the codling moth, or into the cane fields, where the sugarcane borer, a brown moth, deposits her eggs on the stalks of growing cane. What unerring instinct—what scent trail that man knows nothing about—leads her to these places?
Finding the eggs of her prey, by whatever means, the wasp pierces them one by one, depositing one of her own eggs within each. The egg so invaded does not complete its own development but supplies nourishment for the infant parasite now developing within it; thus each parasitized egg becomes a Trojan horse from which will emerge an enemy of its kind.
All these small creatures are working—working in sun and rain, during the hours of darkness, even when winter has damped down the fires of life to mere embers, waiting to flare again into activity as soon as spring awakens the insect world. Under the white blanket of snow, below the frost-hardened soil, in crevices in the bark of trees, and in the shelter of caves, the parasites and the predators are able to tide themselves over the season of cold. The eggs of the mantis are secure in little cases of thin parchment attached to the branch of a shrub by the mother, whose life span ended with the summer that is gone.
The female polistes wasp has taken shelter in a forgotten corner of some attic, carrying in her body the fertilized eggs, the heritage on which the whole future of her colony depends. She, the lone survivor, will start a small paper nest in the spring, lay a few eggs in its cells, and carefully rear a small force of workers. With their help, she will enlarge the nest and develop the colony.
Then the workers, foraging ceaselessly through the hot days of summer, will destroy countless caterpillars. Thus, through the circumstances of their lives and the nature of our own wants, all these creatures have long been our allies in keeping the balance of nature tilted in our favor. Yet now we have turned our artillery against our friends. The terrible danger is that we have grossly underestimated their value in holding off a dark tide of enemies, and that without their help the enemies can overrun us. The prospect of a general and permanent lowering of environmental resistance becomes increasingly real as the number, variety, and destructiveness of insecticides grows.
Each year, we may expect serious outbreaks of insects—both disease-carrying and crop-destroying species—in excess of anything we have ever known. A recent review of the subject contained references to two hundred and fifteen papers reporting or discussing unfavorable upsets in the balance of insect populations because insecticides had killed off various predators and parasites.
Sometimes the end result of chemical spraying has been a tremendous upsurge of the very insect that the spraying was intended to control, as when black flies in Ontario became seventeen times as abundant after spraying as they had been before, and as when, in England, an outbreak of the cabbage aphid—an outbreak that had no parallel on record—followed a broad program of spraying.
The spider mite, for example, has become practically a world-wide pest as DDT and other insecticides have killed off its enemies. The spider mite is not an insect. It is a barely visible eight-legged creature, belonging to the Arachnida, the class that also includes spiders, scorpions, and ticks.
It has a prodigious appetite for the chlorophyll that makes the world green. It inserts its stiletto-sharp mouth parts in the outer cells of leaves or evergreen needles and extracts the chlorophyll. A mild infestation gives trees or shrubbery a mottled, or salt-and-pepper, appearance. When there is a heavy one, foliage turns yellow and fans, which is what happened in some of the Western National Forests a few years ago, following a program of spraying some eighty-five thousand acres of forested lands with DDT.
The spraying was done by the United States Forest Service in , with the intention of controlling the spruce budworm, but the next summer it was discovered that a problem worse than budworm damage had been created. From the air, vast blighted areas could be seen where the magnificent Douglas firs were turning brown and dropping their needles. In the Helena National Forest and on the western slopes of the Big Belt Mountains, and then in other areas of Montana and in Idaho, the forests began to look as though they had been scorched. It was evident that this summer of had brought the most extensive infestation of spider mites in history.
Almost all the sprayed area was affected; nowhere else was any such damage evident. Why does the spider mite appear to thrive on insecticides? Obviously, it is relatively insensitive to them, but there seem to be two other reasons as well. In nature, the spider mite is kept in check by various predators, such as ladybugs, gall midges, predaceous mites, and several pirate bugs, and all of these are extremely vulnerable to insecticides. The other reason has to do with population pressure within the spider-mite colonies.
Normally, a colony of mites is a densely settled community, huddled under a protective web for concealment from its enemies. When such a colony is sprayed, the mites, irritated by the chemicals, scatter in search of places where they will not be disturbed. In doing so, they find a far greater abundance of space and food. Their enemies are now dead, so there is no need for them to spend their energy in secreting a protective web. Instead, they devote it all to producing more mites; it is not uncommon for their egg production to increase threefold.
The situation brought about by insecticides abounds in ironies. In unsprayed orchards, the moths were not abundant enough to cause real trouble. Far off, in the eastern Sudan, a few years later, some sixty thousand acres of cotton were sprayed with DDT. One of the most destructive enemies of cotton is the bollworm, but the more the farmers sprayed, the more bollworms appeared. Unsprayed cotton suffered less damage to its fruits and, later, to its mature bolls than sprayed cotton, and in twice-sprayed fields the yield of seed cotton dropped significantly.
Although some of the leaf-feeding insects were eliminated, any benefit that this might have brought was more than offset by bollworm damage. In America, farmers have repeatedly traded one insect enemy for a worse one as spraying has upset the population dynamics of the insect world. Indeed, both the fire-ant-eradication program in the South and the spraying in the Middle West against the Japanese beetle had precisely this effect; the former permitted the sugar-cane borer to gain a foothold, and the latter resulted in an enormous increase in the corn borer.
A particularly ironic series of events has occurred in the citrus groves of California. In , a scale insect that feeds on the sap of citrus appeared in the state, and within the next fifteen years the fruit crop in many groves was so near a complete loss that the growers gave up and pulled out their trees.
In , however, a parasite of the scale insect was imported from Australia—a small lady beetle called the vedalia. Within only two years, the scale insect was under such thorough control that one could search for days among the orange groves without finding a single specimen. The importation of the vedalia had cost the government a mere five thousand dollars, and its activities had saved the fruitgrowers several millions of dollars a year.
Then, in the nineteen-forties, the citrus growers began to use the glamorous new chemicals in an effort to get rid of other insects, and the populations of the vedalia in many sections of California were wiped out. The scale insect quickly reappeared, and the damage to the citrus trees exceeded anything that had been seen for fifty years. Now control of the scale insect has become enormously complicated. And, regardless of what the citrus growers do, they are more or less at the mercy of the owners of adjacent acreages, growing other crops, for severe damage has been done by insecticidal drift.
If Darwin were alive today, he would be astounded and delighted by the impressive verification that his theories of the survival of the fittest are receiving from the insect world. Under the stress of intensive chemical spraying, the weaker members of the insect populations are being weeded out, and in many areas and among many species only the strong and fit remain, defying our efforts to control them. Nearly half a century ago, a professor of entomology at Washington State College, A.
In the pre-DDT era, when inorganic chemicals were applied in quantities that would seem extraordinarily modest today, strains of insects emerged here and there that could survive spraying or dusting. About , Melander himself ran into difficulty with one of the scale insects. For some years past, the insects, which are a common pest of fruit trees, had been satisfactorily controlled by spraying with lime sulphur, but that year, in the Clarkston area of Washington, they became refractory; they were harder to kill there than elsewhere.
And suddenly the scale insects in other parts of the country seemed to get the same idea—that it was not necessary for them to die under the sprayings of lime sulphur. In Illinois, Indiana, Arkansas, and other states, thousands of acres of fine orchards were destroyed by the insects. Then, in certain areas of California, the time-honored method of placing canvas tents over citrus trees and fumigating them with hydrocyanic acid began to yield disappointing results—a problem that led to research at the Citrus Experiment Station, beginning about and continuing for a quarter of a century.
In the nineteen-twenties, still another insect learned the secret of resistance—the codling moth, which had docilely succumbed to lead arsenate for the previous forty years. It was the advent of DDT and its many relatives, however, that ushered in the true Age of Resistance. It should have surprised no one with even the simplest knowledge of insects or of the dynamics of any animal population that within a matter of a very few years an ugly and dangerous problem had clearly defined itself.
Yet awareness of the fact that insects possess an effective weapon for countering aggressive chemical attack seems to have dawned slowly. In fact, even now only the research workers who are concerned with insects that are vectors, or carriers of disease, appear to have become thoroughly aware of the nature of the situation; the agriculturists, for the most part, still put their faith in the development of ever more toxic chemicals. But if understanding of the phenomenon of insect resistance has developed slowly, it has been far otherwise with resistance itself.
Before , only about a dozen species were known to have developed resistance to any of the pre-DDT insecticides. With the new chemicals and the new methods of intensive application, resistance began a meteoric rise, which by had reached the alarming level of a hundred and thirty-seven species. And no one conversant with the situation believes that the end is in sight. Sometimes resistance develops so rapidly that the ink is scarcely dry on a report hailing successful control of species by means of some specific chemical before an amended report has to be issued.
In South Africa, for example, cattlemen had long been plagued by the blue tick, from which, on one ranch alone, six hundred head of cattle had died in a single year. The tick had for some years been resistant to arsenical dips. Then, about , the chlorinated hydrocarbon called BHC was tried, and for a very short time all seemed to be well.
Reports issued early in the year declared that the arsenic-resistant ticks could be controlled readily with the new chemical; later that year, a bleak notice of developing resistance had to be published. To that list of about a dozen agricultural insects that showed resistance to the inorganic chemicals of an earlier era there have been added a host that are resistant to such chlorinated hydrocarbons as DDT, BHC, lindane, toxaphene, dieldrin, and aldrin, and even to the organic phosphates, from which so much was hoped.
In , the total number of resistant insects of importance in agriculture had reached sixty-five. Resistance in cabbage insects is creating another serious problem. Potato insects are escaping chemical control in many sections of the United States. Although insect resistance is a matter of concern in agriculture and forestry, it is in the field of public health that it has awakened the most serious apprehensions.
The relation between insects and many diseases of man is an ancient one. Mosquitoes of the genus Anopheles may inject into the human blood stream the single-celled organism of malaria. Other mosquitoes transmit yellow fever. Still others carry encephalitis. The housefly, which does not bite, may nevertheless, by contact, contaminate human food with the bacilli of some types of dysentery, and in many parts of the world it also plays an important part in the transmission of eye diseases. The list of diseases and their insect vectors also includes typhus and body lice, plague and rat fleas, African sleeping sickness and tsetse flies, and various fevers and ticks, among innumerable others.
These pose an important problem, which must be solved. No responsible person contends that insect-borne disease should be ignored. The question that has now urgently presented itself is how responsible it is to attack the problem by methods that are rapidly making it worse The world has heard much of the triumphant war against disease through the control of insect vectors, but it has heard little of the other side of the story—the defeats and also the shortlived triumphs that now strongly support the view that the insect enemy has actually been made stronger by our efforts.
What is even more alarming, we may have destroyed our very means of fighting it. A distinguished Canadian entomologist, Dr. Brown, was engaged by the World Health Organization to make a comprehensive survey of the resistance problem.
In the resulting monograph, published in , Dr. The list of resistant species now includes practically all the insect groups of medical importance. Apparently the black flies, the sand flies, and the tsetse flies have not yet become resistant to chemicals. On the other hand, resistance among houseflies and body lice has now developed on a global scale; malaria programs are threatened by resistance among mosquitoes; and the Oriental rat flea, the principal vector of plague, has recently demonstrated resistance to DDT—a most serious development.
Countries reporting resistance among a large number of species represent every continent and most of the island groups. Probably the first medical use of modern insecticides occurred in Italy in , when the Allied Military Government launched a successful attack on typhus by dusting enormous numbers of people with DDT, to control body lice. This program led to one of the earliest and most widely publicized achievements of DDT. Then, in the winter of , DDT controlled lice that had afflicted some two million people in Japan and Korea.
Some premonition of trouble might have been gained by the failure of DDT to control a typhus epidemic in Spain in , but even after that encouraging laboratory experiments led entomologists to believe that lice were unlikely to develop resistance. Events in Korea in the winter of were therefore startling. When DDT powder was applied to a large group of Korean soldiers, the extraordinary result was an increase in the infestation of lice. Some of these lice were collected and tested, and it was found that five-percent DDT powder caused no increase in their natural mortality rate.
Similar results among lice collected from vagrants in Tokyo, from an asylum in Itabashi, and from refugee camps in Syria, Jordan, and eastern Egypt confirmed the ineffectiveness of DDT for the control of lice, and thus of typhus. In , again in Italy, extensive applications of residual sprays for the control of malaria mosquitoes were begun.
The first signs of trouble appeared only a year later. Houseflies and also mosquitoes of the species Culex pipiens —the common house mosquito—began to show resistance to the sprays.
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In , a new chemical, chlordane, was tried as a supplement to DDT. This time, good control was obtained for two years, but by August of chlordane-resistant flies had appeared, and by the end of that year all the houseflies, and the Culex pipiens as well, seemed to be resistant to chlordane. As rapidly as new chemicals were brought into use, resistance developed. By the end of , methoxychlor, dieldrin, and BHC had joined the list of chemicals that were no longer effective.
The flies, meanwhile, had become enormously abundant. The same cycle of events took place elsewhere. What happened in one Egyptian village epitomizes the problem. Insecticides gave good control of flies in , and during the same year the infant-mortality rate was reduced by nearly fifty per cent. The next year, flies were resistant to DDT and chlordane.
The fly population returned to its former level; so did infant mortality. Resistance in other areas followed. Attempts to restore control with dieldrin met with little success; indeed, in some places the flies developed strong resistance to this chemical within two months. After running through all the available chlorinated hydrocarbons, control agencies turned to the organic phosphates, but the story of resistance was simply repeated.
Extensive indoor spraying was begun in , with the usual early success; by , however, observers noticed that adult mosquitoes were resting in large numbers under road bridges, though they were absent from houses and stables that had been treated. Soon this habit of outside resting was extended to caves, outbuildings, and culverts, and to the foliage and trunks of orange trees. Apparently, the adult mosquitoes had become sufficiently tolerant of DDT to escape from sprayed buildings and rest and recover in the open. A few months later, they were able to remain in houses, and were found resting even on treated walls.
This was a portent of the extremely serious situation that has now developed. Resistance to insecticides by mosquitoes of the anophelene group has surged upward at an astounding rate, being created by the very thoroughness of the house-spraying programs designed to eliminate malaria. In , only five species of these mosquitoes displayed resistance; by early the number had risen to twenty-eight. Among other mosquitoes, the pattern is being repeated. A tropical mosquito that carries parasites responsible for such diseases as elephantiasis has become strongly resistant in many parts of the world.
In Some areas of the United States, the mosquito vector of western equine encephalitis, which can be transmitted to man, has developed resistance. An even more serious problem concerns the vector of yellow fever, which for centuries was one of the great plagues of the world. Resistant strains of this mosquito have occurred in Southeast Asia and are now common in the Caribbean region. The consequences of resistance in terms of malaria and other diseases are indicated by reports from many countries. An outbreak of yellow fever in Trinidad in followed failure to control the vector mosquito because of its resistance.
There has been a flareup of malaria in Indonesia and Iran. In Greece, Nigeria, and Liberia, the mosquitoes continue to harbor and transmit the malaria parasite. In Western sections of the United States, loss of control over the mosquito vector of encephalitis poses a problem. A reduction of diarrheal disease that had been achieved in Georgia in the early nineteen-fifties through fly control was wiped out within about a year. A decline in acute conjunctivitis in Egypt in the late nineteen-forties, also achieved through fly control, did not last beyond Less serious in terms of human health, but vexatious as man measures economic values, is the fact that salt-marsh mosquitoes in Florida are also showing resistance.
These are not carriers of disease, but their presence in bloodthirsty swarms had rendered large areas of coastal Florida uninhabitable until control—of an uneasy and temporary nature—was established. But by the late nineteen-forties control had been lost. The fact that the ordinary house mosquito is developing resistance should give pause to many communities that now regularly arrange for wholesale spraying. The wood tick, vector of spotted fever, has recently developed resistance, imitating the brown dog tick, whose ability to escape a chemical death has been widely and thoroughly established for some time.
This ability poses problems for human beings as well as for dogs. The brown dog tick is a semitropical species, and when it occurs in the north it must live through the winter in heated buildings, rather than out-of-doors. John C. Pallister, of the American Museum of Natural History, reported in the summer of that his department had been getting a number of calls from neighboring apartments on Central Park West.
They seem immune to DDT or chlordane or most of our modern sprays. However, laboratory findings on resistance to this group of insecticides in confront the exterminators with the problem of where to go next. Agencies concerned with vector-borne disease are at present coping with their problems by switching from one insecticide to another as resistance develops.
But this cannot go on indefinitely, despite the ingenuity of the chemists in supplying new materials. Brown has pointed out that we are travelling a one-way street. No one knows how long the street is. If the end is reached before control of disease-carrying insects is achieved, our situation will indeed be critical. The chemical industry is perhaps understandably loath to face up to the unpleasant fact of resistance. Yet, however hopefully the industry may turn its face the other way, the problem simply does not vanish.
The cost of insect control by means of chemicals is increasing steadily. For one thing, it is no longer possible to stockpile materials well in advance; the most promising of insecticidal chemicals today may be a dismal failure tomorrow, and the very substantial financial investment entailed in backing and launching an insecticide may be swept away. Rapidly as technology may invent new uses for insecticides and new ways of applying them, it is likely to find the insects keeping a lap ahead. There are good reasons for this.
Spraying kills off the weaklings. Inevitably, it follows that intensive spraying with powerful chemicals only aggravates the condition that it is designed to correct. After a few generations, there is no longer a mixed population of strong and weak insects but, instead, a population consisting entirely of tough, resistant strains. In an Army camp In southern Taiwan, for example, bedbugs were found actually carrying deposits of DDT powder on their bodies.
When these bedbugs were experimentally placed in cloth impregnated with DDT, they lived for as long as a month, and laid their eggs there; the resulting young grew and thrived. The means by which insects resist chemicals are not yet thoroughly understood, but it is thought that they probably vary.
Some of the insects that defy chemical control are believed to be aided by some sort of anatomical advantage, but there is little accurate information on this point. The quality of resistance does not necessarily depend on physical structure, however. DDT-resistant flies possess an enzyme that allows them to detoxicate the insecticide to the non-toxic chemical DDE. The enzyme occurs only in flies that possess a hereditary factor for DDT resistance. Flies and other insects are believed to detoxicate the organic-phosphate chemicals by means of other enzymes.
Some behavior pattern may also place the insect out of reach of chemicals. Many fieldworkers in spraying campaigns have noticed the tendency of resistant flies to rest on horizontal surfaces, which are seldom treated, rather than on walls, which habitually are. Some malaria mosquitoes that have been sprayed in huts have a habit that reduces their exposure to DDT so drastically as to make them virtually immune. Irritated by the spray, they leave the huts, and outside they survive. Usually, resistance takes two or three years to develop.
Occasionally, however, it will do so in only one season, or even less; at the other extreme, it may take as long as six years. The number of generations produced by an insect population in a year naturally accounts for a good part of the difference, and this varies with species and climate. Flies in Canada, for example, have been slower to develop resistance than flies in our Southern states, where long, hot summers favor a rapid rate of reproduction. Resistance is not something that develops in an individual. If an individual possesses at birth some quality that makes him less susceptible than others to a certain poison, he is more likely to survive and to produce children.
Resistance develops in a population only after a lapse of 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. Our aim should be to guide natural processes as cautiously as possible in the desired direction rather than to use brute force. 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. Humbleness is in order; there is no excuse for scientific conceit here. Over the past decade, most of those people who are best fitted to develop natural controls have been laboring in the more exciting vineyards of chemical control.
Why does this situation exist? One important reason is that major chemical companies are pouring money into the universities to support research on insecticides. Biological-control studies are never so well endowed, for the simple reason that they do not promise anyone the sort of fortune that is to be made in the chemical industry.