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Mosquitos – those 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 climates – from 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-cooking – they 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 yet – it'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 simple – most 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.
But – hey 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!
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What Happens to Your Body When a Mosquito Bites You

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zx12960q 2019 年 9 月 22 日 に公開

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