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  • Mosquitosthose brazen little buggers that buzz off with a bellyful of your blood.

  • Bah-humbug!

  • They can ruin a nice picnic in the park, camping out with your friends, even your own humble

  • abode!

  • Ugh, mosquitos are the single worst thing about summer!

  • Why do they have to bite, and why does it itch like crazy?

  • It's high time we got some answers!

  • Nature is a strange thing indeed.

  • Australia's got platypuses - mammals that lay eggs and have beaks like ducks.

  • There are jellyfish that can potentially live forever.

  • There are so many exotic and extremely rare creatures that can be called true oddities

  • or even miracles of nature.

  • But mosquitos?

  • Come on, they're nothing like that!

  • They're innumerable, and they come in swarms just about anywhere you go.

  • Still, and I really don't want to accept it myself, they appear to be a miracle of

  • nature as well!

  • First of all, mosquitos are ancient critters thought to have evolved between 50 and 100

  • million years ago.

  • That means even the dinosaurs weren't free of their irritating presence.

  • (Imagine a T-Rex trying to swat one away!

  • With his tail -- Poor thing…)

  • And, of course, they spread everywhere.

  • Chances are the first human being on this planet was bitten by a mosquito probably more

  • than once in their life!

  • Mosquitos proved to be a highly adaptable species.

  • Except for Antarctica, they live on all continents in a variety of climatesfrom tropical

  • Sub-Saharan Africa to the cold forests of Siberia Russia.

  • There are about 3,000 different species of mosquitos all around the world.

  • All they need for survival is some water and a warm meal.

  • No, not your Granny's home-cookingthey only want what's pumping through your veins!

  • So, how did they become adapted to feed on the blood of animals?

  • Just to get things straight right from the start, not all mosquitos suck blood.

  • I'm not talking about different species of this insect but about severe differences

  • between female and male mosquitos.

  • Only females drink blood, while male specimen feed solely on nectar.

  • It's as if all the men on Earth were exclusively vegetarian by nature!

  • Such a critical difference in feeding behavior between males and females is extremely rare.

  • The good news is, you can tell the difference between the two!

  • Male mosquitos are a bit smaller than females.

  • And if you see one nearby with fancy-looking feathered antennae, don't rush to smack

  • it just yetit's a male and it won't bite you no matter what.

  • You see, the wings of female mosquitos move so swiftly that they resonate on a very high

  • frequency from 300 to 500 beats per second.

  • This makes that annoying high-pitched buzzing sound that can have you scouring your house,

  • slipper in hand.

  • The males' feathered headpieces are specifically attuned to locate this sound so that they

  • can find a mate.

  • As for the antennae of female mosquitos, they're smooth.

  • A mosquito's lifespan is only about a month or two.

  • Well, that's for the females.

  • The guys live a lot shorter: around 2 weeks.

  • All this time, they must keep busy, especially females since their job is a lot harder.

  • They need to find a source of blood meal to be able to produce eggs.

  • But I'll go into that more a bit later.

  • Once their eggs are ready, it's time to find a nice place with standing water to release

  • them.

  • Since they're in a race against time, they look for a source of blood usually within

  • 1 or 2 miles of the breeding ground.

  • And that's exactly why you shouldn't have any standing water near your house if you

  • don't want a mosquito invasion!

  • Ok, but what about that bug zapper you have on your front porch?

  • Sorry, not much use here.

  • Contrary to popular belief, mosquitos don't search for their prey looking for lights.

  • To be fair, there aren't many species that prefer human blood at all.

  • Most of them would rather feed off mammals that, ya know, don't grab a shoe or newspaper

  • and squish them!

  • But there are even more that like to feed only on birds or even reptiles and amphibians.

  • Well, if they don't use light, then how do they find you?

  • They have a variety of methods, but they mostly use scent.

  • More specifically, they're sniffing for your body heat and the one thing every living

  • breathing thing produces constantly: carbon dioxide, or CO2.

  • Every time you exhale, you allure loads of flying pests.

  • A mosquito can sense a tiny concentration of pure CO2 in the air from more than 75ft

  • away!

  • Hey, just hold your breath!

  • Well no.

  • At closer distances, they'll go towards the heat and anything that moves.

  • They have a couple things to help them with that latter bit: 1) compound eyes with hundreds

  • of lenses that give them a wide field of vision and 2) tiny hairs all over their body that

  • guide them towards the movement of big animals.

  • So when you're out mowing the lawn, your body is moving the air around you, and the

  • tiny hairs on a mosquito's body can sense this!

  • Still, the true mystery of mosquitos is in their feeding habits.

  • What you perceive only as a short stinging feeling is, in fact, a long and ingenious

  • process.

  • When a mosquito finds its prey, it approaches it carefully.

  • The buzzing kinda gives them away, but I guess they can't do much about that since the

  • sound comes from their flapping wings.

  • The task is even more difficult since they need 3 minutes to fill their belly.

  • That's 3 minutes of the constant threat of being smashed by their prey!

  • Has anyone ever told you that waving your hands or swatting at mosquitos to scare them

  • away is pointless?

  • Next time, you can answer back with this: a 2018 study led by biologist Dr. Jeff Riffell

  • proved that mosquitos can remember the scent of a particularly aggressive prey and avoid

  • it completely for 24 hours.

  • That means, if a mosquito tries to bite you and you decide to brush it off or swat at

  • it, it'll probably choose someone else to bite next!

  • And that's wise of it because even if it manages to land undetected, it won't be

  • able to sting immediately.

  • A mosquito's mouthpiece, or proboscis, is far more complex than just a sharp straw to

  • suck blood through.

  • It consists of 6 separated long and thin parts called stylets protected by an outer lip of

  • sorts.

  • Yes, they stick not 1 but 6 needles in you!

  • Some of those have razor-sharp teeth that cut through the skin.

  • Fun fact: medical scientists were inspired by the form of a mosquito's stylet to make

  • needles less painful!

  • Well that's good.

  • Other parts of a mosquito's feeding equipment serve different purposes.

  • Some find blood vessels in the skin, and others inject the mosquito's saliva.

  • The saliva itself is crucial in the whole process.

  • Remember, they need around 3 minutes to get enough blood.

  • But the most dangerous part is the moment they pierce the skin because that's when

  • the prey can feel the bite.

  • So, the mosquito injects its saliva immediately after it bites you.

  • The saliva consists of more than 100 different components, most of which are these organic

  • substances called enzymes.

  • They serve one purpose: to stop blood from clotting and improve its flow.

  • There are also other components used like a local anesthesia.

  • From the moment they're in, the prey won't feel anything.

  • That is, until the mosquito leaves and the bite mark starts itching.

  • The reason for that reaction is simplemost people are allergic to those enzymes.

  • And I say 'most' because there are those rare individuals who won't itch at all if

  • a mosquito bites them!

  • Hah!

  • Must be nice!

  • But the last and most important question remains: why do they need blood?

  • Especially if the males can just live off nectar.

  • Like I touched on earlier, females need blood to develop eggs.

  • More specifically, she needs loads of protein and iron, which blood happens to be rich in.

  • After a good meal and a belly bloated full of the red stuff, a mosquito will need a day

  • or two off just to digest it.

  • Then, she lays her eggs, and the whole cycle starts again.

  • Good thing we don't take first place on her menu of preferred meals!

  • And we humans are well prepared for their invasion no matter how many of them come.

  • My only advice is to use methods that mask your scent, like candles, herbs, and sprays.

  • The best traps are probably the ones that properly use science to lure mosquitos to

  • their demise in masses by producing the carbon dioxide they seek.

  • Still, any repellent will do the trick so that you're not left itchin' like the

  • dickens!

  • Alright, how about you?

  • What do you do to keep mosquitos at bay?

  • Leave your tips down in the comments!

  • If you learned something new today, then give this video a like and share it with a friend.

  • Buthey now! – don't go buggin' out just yet!

  • We have over 2,000 cool videos for you to check out.

  • Just click on that video to the left or right, and enjoy!

  • Stay on the Bright Side of life!

Mosquitosthose brazen little buggers that buzz off with a bellyful of your blood.

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蚊に刺されたらどうなるの? (What Happens to Your Body When a Mosquito Bites You)

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    zx12960q に公開 2021 年 01 月 14 日
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