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  • What's the worst bug on the planet?

  • You might vote for the horsefly or perhaps the wasp, but for many people, the worst offender is by far the mosquito.

  • The buzzing, the biting, the itching, the mosquito is one of the most commonly detested pests in the world.

  • In Alaska, swarms of mosquitoes can get so thick that they actually asphyxiate caribou.

  • And mosquito-borne diseases kill millions of people every year.

  • The scourge that is the mosquito isn't new.

  • Mosquitoes have been around for over a hundred million years and over that time have coevolved with all sorts of species, including our own.

  • There are actually thousands of species of mosquitoes in the world, but they all share one insidious quality:

  • They suck blood, and they're really, really good at sucking blood.

  • Here's how they do it.

  • After landing, a mosquito will slather some saliva onto the victim's skin, which works like an antiseptic, numbing the spot so we don't notice their attack.

  • This is what causes the itchy, red bumps, by the way.

  • Then the bug will use its serrated mandibles to carve a little hole in your skin, allowing it to probe around with its proboscis, searching for a blood vessel.

  • When it hits one, the lucky parasite can suck two to three times its weight in blood.

  • Turns out, we don't really like that too much.

  • In fact, humans hate mosquitoes so much that we spend billions of dollars worldwide to keep them away from us.

  • From citronella candles to bug sprays to heavy-duty agricultural pesticides.

  • But it's not just that mosquitoes are annoying, they're also deadly.

  • Mosquitoes can transmit everything from malaria to yellow fever to West Nile virus to dengue.

  • Over a million people worldwide die every year from mosquito-borne diseases, and that's just people.

  • Horses, dogs, cats, they can all get diseases from mosquitoes too.

  • So, if these bugs are so dastardly, why don't we just get rid of them?

  • We are humans after all, and we're pretty good at getting rid of species.

  • Well, it's not quite so simple.

  • Getting rid of the mosquito removes a food source for lots of organisms like frogs and fish and birds.

  • Without them, plants would lose a pollinator.

  • But some scientists say that mosquitoes aren't actually all that important.

  • If we got rid of them, they argue, another species would simply take their place and we'd probably have far fewer deaths from malaria.

  • The problem is that nobody knows what would happen if we killed off all the mosquitoes.

  • Something better might take their spot or perhaps something even worse.

  • The question is, are we willing to take that risk?

What's the worst bug on the planet?

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