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  • In 2018, a cockroach crawled inside a sleeping man's ear

  • and laid an egg sac.

  • Luckily, roaches don't go out of their way to do this,

  • so it doesn't happen very often.

  • But there are a bunch of other unsavory bugs

  • that will lay eggs all over your body on purpose.

  • First up, the human botfly.

  • These insects, which are native to Central

  • and South America, glue their eggs to mosquitoes

  • and other blood-sucking insects.

  • When the mosquito bites you, the eggs hatch.

  • Then the larvae wriggle into your skin,

  • creating a painful pimple that leaks pus.

  • Or, as the baby botflies call it, lunch.

  • After five to 10 weeks, they escape.

  • Not long after that, they reach adulthood,

  • ready to mate, and start the cycle all over.

  • Another tropical parasite is Tunga penetrans,

  • more commonly known as the sand flea.

  • Females burrow into the bottom of your foot

  • and slurp your blood.

  • They start off smaller than a grain of sand

  • but grow to 2,000 times their size within a week

  • as they swell with your blood and up to 200 eggs.

  • Those eggs fall to the ground and hatch,

  • waiting for the next bare foot to pass by.

  • But some egg-laying parasites go more than just skin deep.

  • Tapeworms, for example, invade your intestines.

  • Adults can grow to be longer than a bowling lane

  • and block up your digestive system.

  • But it gets worse,

  • because they lay tens of thousands of eggs,

  • which can hatch and migrate,

  • spreading throughout your lungs,

  • muscles, and even your brain.

  • If that sounds gruesome, just wait till you hear

  • about the Loa loa worm.

  • It can be passed from human to human

  • by hitching a ride inside of deer flies.

  • When the flies bite you, the larvae enter through the wound.

  • After five months growing beneath your skin,

  • they reach adulthood and start to release

  • thousands of embryos a day.

  • Sometimes you can even see the worms

  • moving under your skin or across your eyeball.

  • But, hey, not every egg-laying invader is sinister.

  • Face mites, for example, are pretty innocuous.

  • They live on pretty much everyone's face,

  • and most people just never notice.

  • After all, they feed on facial oil, not flesh.

  • When it comes time to breed,

  • females just lay one egg inside of your pores.

  • Even better, researchers can now study your face mites

  • to track how your ancestors migrated across the planet,

  • because we usually pass them from parent to child,

  • so the mites stay in the family.

  • But face mites aren't the only helpful bug around.

  • Green bottle flies might be useful in medicine.

  • They lay their eggs inside of open wounds,

  • and then the maggots hatch and devour the damaged flesh.

  • That sounds brutal, but one day

  • we might be able to harness this process

  • to treat diabetic foot ulcers

  • and other slow-healing wounds.

  • Because when the maggots go to town,

  • they actually clean the area

  • and remove a lot of the dead tissue.

  • They even secrete proteins that reduce inflammation.

  • So maybe botflies, fleas, and tapeworms

  • could learn a thing or two

  • and at least make themselves useful

  • if they're going to move right in.

In 2018, a cockroach crawled inside a sleeping man's ear

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B2 H-INT hatch lay egg skin egg laying adulthood

The Bugs That Lay Eggs All Over Your Body

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    林宜悉   posted on 2020/10/24
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