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You’re probably pretty familiar with the high-pitched buzz of a pesky mosquito
that just airlifted off your body, and the realization that you will be scratching
the bite it has left behind for quite a while.
And this whole ordeal isn’t just an annoyance for many people.
Some species are a major source of disease,
transmitting things like dengue fever, Zika, malaria, and yellow fever.
It might be tempting to use bug spray
or any type of insecticide to keep mosquitoes at bay.
But more often than not, this only kills weaker bugs, leaving behind the ones
that are stronger and potentially more resistant to these chemicals.
Which could be pretty bad for us long-term, so scientists are working on
some non-insecticide ways of controlling mosquito populations.
Female mosquitoes are the only ones that bite and transmit disease.
So, one of the options that scientists are investigating to control
mosquito populations is turning female mosquitoes into males.
No more females means no more disease.
In humans and other mammals,
sex is determined largely by the sex chromosomes.
But in other animals like insects…things are more nuanced.
You see, in some mosquito species like the Aedes aegypti,
having a Y chromosome isn't the end all be all of being male.
In fact, in this species, it’s actually determined
by a single male-determining gene within the Y chromosome.
That gene is known as Nix, and it’s located in a specific spot
in the mosquito’s Y chromosome, called the M locus.
And researchers have found that by simply inserting the Nix gene into female
mosquito chromosomes, that gene can trigger a switch from female to male.
So scientists are working on manipulating mosquito genes in females so that they
would all express an extra copy of the Nix gene, creating a fertile male mosquito.
And since this gene is in one of the sex chromosomes, the mosquito can then
pass the extra copy of the Nix gene on to its offspring that it creates
with fertile female mosquitoes to create more fertile male mosquitoes.
Eventually, all of the mosquitoes would be born male
and female mosquitoes would cease to exist.
And no more females means no more mosquito bites,
and eventually, down the road, no more mosquitoes.
The diseases transmitted by this species just wouldn’t happen.
Another way scientists are looking to get rid of mosquitoes
is by just sterilizing them.
And some researchers are already doing just that!
They’re raising male mosquitoes in labs and irradiating them to damage their DNA
and make them sterile, because remember, only the females bite.
Then, they release those unfertile males into the wild
and the females breed with them, but then they don’t have any babies.
And eventually, hopefully, you see a decline in the mosquito population.
This eradication method is a tried-and-true technique
that’s been in place since the 1950s.
Researchers have successfully used it on the Mediterranean fruit fly
and New World screwworm fly,
and are currently working on two types of mosquitoes in Florida and Italy.
If implemented correctly, sterilizing mosquitoes can be an environmentally friendly,
cost-efficient, and effective method of decreasing the natural mosquito population.
But scientists are erring on the side of caution, because they don’t want to
accidentally transmit any unintended consequences of irradiating mosquitoes
onto the creatures that the mosquitoes feed on, like, for example, us.
And some might have reservations around the idea
of wiping out mosquito populations altogether.
It is true that every species plays a role in its environment, even mosquitoes.
We did a whole episode on the impacts of wiping out all mosquitoes,
and it basically comes down to the idea that it would be really, really hard
to wipe out all the mosquitoes on this planet, because they reproduce so dang fast
and there are over 3000 species of them on Earth.
But if researchers can focus their efforts on eradicating the mosquito species that
are vessels for human diseases, which is a mere fraction of all mosquito species,
that would really go a long way toward improving public health concerns
and deaths from mosquito-transmitted diseases.
Not to mention, the risk of just having an unpleasant summertime
would go down as well.
Could you imagine this: No more annoying buzzing, no more itchy welts,
no more stinky bug spray?
Killing all the mosquitoes feels like a win-win to me!
And something else that might be a win-win for you is learning something
completely new or brushing up on a few science topics,
and there's no better place for that than Brilliant.
Brilliant is an interactive STEM-learning platform that helps you learn concepts
by working through them in visual, hands-on ways.
Brilliant has an extensive course catalog including one about statistics
fundamentals, where you can mathematically quantify predictions,
like, how many mosquitos you need to irradiate to decrease twice their population.
And if you get stuck at any point,
they have explanations to help you find out more and learn at your own pace.
If you’d like to check them out you can click the link in the description down below
or visit Brilliant.org/SciShow to get 20% off the annual Premium subscription.
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