Interaction With Humans
In the past, Native Americans ate the flesh of horseshoe crabs, and used the tail spines as spear tips and the shells to bail water out of their canoes. More recent attempts to use horseshoe crabs as food for livestock were abandoned when it was found that this gave the meat a bad taste. Horseshoe crab blood contains a clotting agent, Limulus Amebocyte Lysate, which is now used to test antibiotics and kidney machines to ensure they are free of dangerous bacteria, and to detect spinal meningitis and some cancers.
Cooked tarantula spiders are considered a delicacy in Cambodia, and by the Piaroa Indians of southern Venezuela. Spider venoms may be a less polluting alternative to conventional pesticides as they are deadly to insects but the great majority are harmless to vertebrates. Possible medical uses for spider venoms are being investigated, for the treatment of cardiac arrhythmia, Alzheimer's disease, strokes, and erectile dysfunction. Because spider silk is both light and very strong, attempts are being made to produce it in goats' milk and in the leaves of plants, by means of genetic engineering. There were about 100 reliably reported deaths from spider bites in the 20th century, compared with 1,500 from jellyfish stings.
Scorpion stings are thought to be a significant danger in less-developed countries, for example they cause about 1,000 deaths per year in Mexico but only one every few years in the USA. Most of these incidents are caused by accidental human "invasions" of scorpion's nests. However medical uses of scorpion venom are being investigated for treatment of brain cancers and bone diseases.
Ticks are parasitic, and some transmit micro-organisms and parasites that can cause diseases in humans, while the saliva of a few species can directly cause tick paralysis if they are not removed within a day or two.
A few of the closely related mites also infest humans, some causing intense itching by their bites and others by burrowing into the skin. Species that normally infest other animals such as rodents may infest humans if their normal hosts are eliminated. Three species of mite are a threat to honey bees and one of these, Varroa destructor, has become the largest single problem faced by beekeepers worldwide. Mites cause several forms of allergic diseases, including hay fever, asthma and eczema, and they aggravate atopic dermatitis. Mites are also significant crop pests, although predatory mites may be useful in controlling some of these.
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Famous quotes containing the words interaction with, interaction and/or humans:
“Recent studies that have investigated maternal satisfaction have found this to be a better prediction of mother-child interaction than work status alone. More important for the overall quality of interaction with their children than simply whether the mother works or not, these studies suggest, is how satisfied the mother is with her role as worker or homemaker. Satisfied women are consistently more warm, involved, playful, stimulating and effective with their children than unsatisfied women.”
—Alison Clarke-Stewart (20th century)
“The act of putting into your mouth what the earth has grown is perhaps your most direct interaction with the earth.”
—Frances Moore Lappé (b. 1944)
“It is quite a common and vulgar thing among humans to understand, foresee, know and predict the troubles of others. But oh what a rare thing it is to predict, know, foresee and understand one’s own troubles.”
—François Rabelais (1494–1553)