These men were late nineteenth-century entomologists, a humble vocation by the standards of the day. But the U. Department of Agriculture—new then, having been formed in —asked them to accomplish something not so humble: they were to learn everything there was to know about agricultural pests, and then to destroy them.
The intended beneficiaries of this project were panicked farmers whose fields were being decimated by insect invasions. Riley and Howard were charged with exterminating the very creatures they studied. If the irony registered, they never said so. Riley was the older of the two gentlemen. His big idea—the great one—was to merge the observational folk-wisdom of everyday farmers with the financial largesse of the federal government to help insects kill insects.
Biological control, we now call it. If the concept of exterminating insects with insects seemed moony, American farmers were game.
Between and —a time when agriculture began to pursue high-yielding monoculture in earnest—armies of chinch bugs, locusts, San Jose scales, boll weevils, Colorado potato beetles, and Hessian flies capitalized on the smorgasbord, moving steadily eastward and shredding the foodscape with biblical power.
He rode his bike all over D. He had six kids and doted on them. Like many entomologists, he was a brilliant illustrator of insects. When he taught entomology classes at the University of Missouri in the s, he was so thrilled to be talking shop that he would draw insects on the board with both hands at once. He grew his hair into a cascade of curls and his students adored him. Riley was instinctively wary of these new concoctions—amateurish compounds of arsenic and lead and kerosene—being sprayed and dusted over arable land and healthy soil.
Charles Darwin, for one, sent him a little fan note. Riley knew his way around a farm. DEET's most significant benefit is its ability to repel potentially disease-carrying insects and ticks. The Centers for Disease Control and Prevention CDC receives more than 30, reports of Lyme disease transmitted by deer ticks and reports of La Crosse encephalitis virus transmitted by mosquitoes annually. Each of these diseases can cause serious health problems or even death in the case of encephalitis.
Where these diseases are prevalent, the CDC recommends use of insect repellents when out-of-doors. View more information on specific products and their protection times. FIFRA requires that pesticides be used according to the approved label. Always follow the recommendations appearing on the product label. The following additional statements will appear on the labels of all aerosol and pump spray formulation labels:.
DEET is approved for use on children with no age restriction. There is no restriction on the percentage of DEET in the product for use on children, since data do not show any difference in effects between young animals and adult animals in tests done for product registration. EPA continues to believe that the normal use of DEET does not present a health concern to the general population, including children. If you suspect that you or your child is having an adverse reaction to a DEET product, discontinue use of the product, wash treated skin, and call your local poison control center or physician for help.
If you go to a doctor, take the repellent container with you. How does fly spray work? In short, fly spray insecticides disable the acetylcholinesterase enzyme that a fly needs to relax its muscles.
The non-stop muscle contraction then makes it impossible for it to breathe, so it suffocates to death. To understand precisely how fly spray works, we first need to understand some of the chemistry behind muscle contraction. Acetylcholine ACh is an organic chemical used as a neurotransmitter in the bodies of many many living things—including you and me; ACh is used to send messages from nerve cells to other cells such as muscle cells.
One such use-case is in the neuromuscular junction NMJ , where the motor neurons release ACh in order to stimulate muscle contraction. Then, an enzyme called acetylcholinesterase is released into the NMJ to catalyze the breakdown of ACh, thereby relaxing the muscles. Fly spray insecticides contain organophosphate compounds which bind to the acetylcholinesterase enzyme and prevent it from being used to break down ACh in the NMJ.
As a result of this, the fly cannot relax its muscles, causing it to enter a tetanic seizure, starving of oxygen before collapsing into its asphyxia death.
Perhaps a few seconds longer for particularly large bugs. Some of the movement you might see after those initial 10 seconds or so are possibly down to continued post-mortem muscle spasms. Particularly strong or large flies might struggle for a little longer. Many fly spray aerosols market themselves as being lethal to wasps or cockroaches as well as houseflies. Does fly spray kill spiders? Well, yes, eventually. Depending on the size of the arachnid in question, it will just require a larger spray dosage and more time for them to die.
The question of whether insects have the capacity to experience pain is a long-standing and ongoing debate among scientists and ethicists alike.
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