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Name: Burbank School
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Why do mosquito bites itch?

I believe itching is understood to be a very small pain feeling, so then the question becomes why do mosquito bites hurt. The simple answer is because the skin is damaged by the bite. But I think it's important that it is damaged chemically more than physically, by a substance in the mosquito's saliva that it injects to prevent the blood clotting while it tanks up. There are beasts that can suck your blood without the process hurting, including leeches and vampire bats (I think). Leeches are used in surgery to drain excess blood for this reason. You'd think that over time mosquitoes would evolve painless anti-clotting spit, so they can drink in peace without alarming you by the hurt and making you swat them. But, on the other time, perhaps *we* have evolved the pain as a warning sign that we are being bitten, and nasty diseases (encephalitis, malaria) may be being transmitted.

Christopher Grayce

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