I could pretty much guarantee you that you won't find anyone who doesn't really, really

hate mosquitoes. Like, that noise that they make when they're flying around your ears

is the worst thing. It's true that every organism has an important role to play in its ecosystem,

but from a human perspective, mosquitoes... they suck. I'm sure that you could rattle

off dozens of things you hate about mosquitoes, starting with their horribly itchy bites,

but I can think of at least three right off the top of my head.

Number one: there are only two basic kinds of mosquitoes. Hungry ones, and lazy ones.

Of the three thousand species of mosquitoes in the world, most actually don't bite humans.

But the ones that do are plenty annoying on their own. Female mosquitoes, first of all,

are the only ones that actually bite people. They need a protein found in animal blood

called isoleucine in order to produce eggs. So if they're going to make their month long

lives worthwhile, they need to stock up, and fast. As a result, lady mosquitoes spend most

of their brief lives in a ravenous search for blood meals, drawing blood from any vertebrate

they can find. The males, they don't really do anything. They live for an average of about

10 days, and other than spending a couple of seconds mating, they just lay around, drinking

nectar from flowers and probably watching football or something.

Reason number two to hate mosquitoes: They're total discriminatory jerks. If you've ever

suspected that mosquitoes have been picking on you while leaving other people alone, you

were probably onto something. Mosquitoes actually target, like profile you might say, certain

kinds of people when they are looking for a blood meal. You might have heard that mosquitoes

are attracted to carbon dioxide and body heat, and that is true. Mosquitoes figure if you

are exhaling and you have a pulse, then you probably are a thing that has blood. But some

of us are hotter and exhale more than others. So studies have found that pregnant women

for example, tend to be singled out by mosquitoes because of their elevated body temperate.

And obese people have been found to suffer more bites because larger people simply produce

more CO2. Though mosquitoes can also detect a whole range of chemical compounds coming

out of us that we're not even aware of, like lactic acid, which we produce by metabolizing

milk, and octenol, a type of alcohol we secrete after eating certain kinds of fatty acids.

But the craziest way mosquitoes discriminate is based on our blood type. We each have a

blood type determined by a chemical marker, called an antigen, that forms on our red blood

cells. But some of us, for genetic reasons, actually have those blood type antigens circulating

through our bodies, and we secrete them through our skin and in all of our bodily fluids.

About 80% of us are these so called "secretors", and if you're one of them, that means that

mosquitoes can not only smell your blood from far away, they can actually tell what type

you are. Research has repeatedly shown that mosquitoes bite secretors more often than

non-secretors, and for some reason, they also prefer people with the "O" blood type, like

me. If that isn't discriminatory, I don't know what is.

But the biggest reason mosquitoes suck, is simply because they kill more people than

any other animal on earth. Because of their blood sucking habits and plentifulness, mosquitoes

are the most effective vectors, or carriers of disease, in the world. Every year, 30,000

people die from yellow fever for example, a viral disease transmitted by the bites of

mosquitoes throughout Africa and the Americas. Dengue fever is on the rise in the Americas

thanks these little turd wads, and then there's malaria, an incurable disease caused by the

parasite plasmodium, and its only way of getting around is by mosquito. There are more than

200 million cases of malaria worldwide, and every year more than 600,000 people die from

it, the vast majority of its victims in Africa. It's estimated that more than one million

people die every year from all the diseases carried by mosquitoes. And if you want to

do something about it, then visit our friends at malarianomore.org. Explore the science,

get the latest news, and find out how you can literally decrease world suck by fighting

the spread of mosquito-born diseases

Thanks for checking them out, and thanks for watching this SciShow Dose. If you want to

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