good question
if you want to read an absolutely mind blowingly fascinating book, check out tompkins "the secret life of plants" then try his "the secret life of soil" if you like the first one.
the insects, microbes, worms, etc job is to break down dead or diseased organic material in order to regenerate and recreate life. but! if they attacked and broke down healthy plants, then there would be no forest left! it would all be gone, gobbled up by critters. so the question is - how do they know what to eat and what not to eat?
experiments have shown that diseased plant (and human!) tissue sends out a signal of a specific frequency, this signal is picked up by insects and they hone in on it, becuase they know it dinner time. this signal is essentially like a dinner bell to them, its nature's way of saying, "okay, time to start the break down process, go gobble"
healthy tissue, on the other hand, emits a different signal that says "i am thriving here" and the insects stay away.
as for mcdonalds, it doesn't rot cause its not food.
this link mentions phillip callahan, another fascinating author to look into.
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http://www.beorganic.com/februarynews01.html
Some people still consider insects “pests”. The presence of numerous insects on a given plant indicated not a problem in itself, but a symptom of a larger problem.
Healthy plants all emit a low level of electromagnetic radiation. Every variety has a distinct resonant frequency in the infrared band. A stressed plant cannot maintain resonance and emits at a dissonance, which signals to insects its imminent demise. The insects are simply doing their assigned task.
All insects are endowed with antennas. They use these to communicate in the infrared range, as well as to determine the location of stressed plants. Electronics engineers have designed all manner of antenna shapes, every single one of which can be found in the insect world.
Insects also utilize ultraviolet light to see at night through their multi-lensed eyes. The pioneering entomologist, Dr. Phillip Callahan, has revealed most of this to us.
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this study shows diseased human flesh emits sickly radiation!
http://www.raven1.net/seclife.htm#DISEASERAD
.. Meanwhile, the research of the Russian Alexander Gurwitsch, which inspired L. George Lawrence to begin his study of the potentialities of biocommunication, despite its rejection by the U.S. Academy of Sciences, began to get a new lease on life. The distinguished bacteriologist at Cornell University, Professor Otto Rahn, was amazed to find that whenever any of his laboratory workers fell ill THEY APPEARED TO CAUSE THE DEATH OF YEAST CELLS WITH WHICH THEY WERE EXPERIMENTING. A few minutes' exposure to their fingertips EVEN AT A DISTANCE would kill vigorous cells of this carbohydrate fermeniting fungus. Further investigation showed that a chemical compound excreted from the hands and faces of the sick technicians was responsible; but how it ACTED AT A DISTANCE was a mystery. Rahn went on to prove that the continually renewed tissue of the cornea of the eye, as well as most wounds and cancer tumors, EMIT RADIATION; he set these and other findings down in a book, Invisible Radiation of Organisms, which on the whole was ignored by his colleagues.
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