When the weather warms, fruit flies just appear.

Out of nowhere.

Next to the fruit bowl, near the trash, everywhere.

And once they arrive, they are determined to stay

no matter how many you swat, squash, or seize.

Now as far as we know, fruit flies can't teleport

into our homes from another grosser dimension.

So where do they come from, and why are they so hard

to get rid of?

Meet Drosophila melanogaster:

your standard fruit fly.

It can smell a meal from more than a kilometer away

all thanks to the tiny antennae on top of its head.

These antennae are specially attuned to

sniff out chemicals like acetic acid

let off by rotting fruit,

and once they're locked on to the scent,

it's nearly impossible to keep them out of your home.

That's because fruit flies are about

the size of a sesame seed,

so they can slip through almost any crack,

screen, or gap.

But contrary to popular belief,

it's not just the smelly fruit they're after.

They're also hunting for the source of that rotting stench,

specifically, fungi and other microorganisms.

Yum!

And once they land for the feast, things turn even nastier.

You know how you never see just one fruit fly?

That's because they have incredibly fast life cycles.

A single female fruit fly can

lay up to 100 eggs a day, which hatch in less than 24 hours.

The maggots then tunnel under the fruit skin,

feeding on the microbial rot.

In just a few days later, they pupate

into fully fledged fruit flies.

By the time day 11 or 12 rolls around,

they're ready to have little maggots of their own.

Aww.

That's why your home can go from fruit-fly free

to infested in under two weeks.

Now, by this point you might start

swatting them down one by one.

But it's not so easy, right?

Perhaps even...fruitless?

Well, scientists have discovered why.

Turns out fruit flies are mathematical wizards of escape.

For starters, they have around 270-degree vision,

so they can see you coming from almost any angle:

front, back, or side to side,

and they will actually calculate the angle

of your attack and plan their escape accordingly

all in as little as 100 milliseconds.

Scientists figured this out because

of how a resting fruit fly will reposition

its legs when it senses an attack.

If your hand's coming from the front, for example,

fruit flies move their middle legs forward,

lean back, and raise their legs, allowing for

a fast backwards takeoff.

Once in midair, killing them isn't much easier.

They can change directions within

one one-hundredth of a second and quickly accelerate

by flapping their wings 200 times per second.

Not bad for a brain that's even smaller

than a house fly's.

So then, how do you get rid of them?

Some experts suggest making a trap.

Fill a container with 2 centimeters of cider vinegar,

cap it with a funnel, and then tape around the perimeter

so that no flies can crawl out.

You see, fruit flies are smart enough to find fruit

but not the hole they entered.

But here's the thing.

Even if you trap every last fly,

they will come back as long as there's something to eat.

And unfortunately for you, fruit flies aren't picky.

They love rotten fruit, sure,

but wine and other fermented liquids,

which are chock-full of those microbes they adore,

are also tasty,

as is the slime that builds up in your kitchen sink.

So really, the only thing you can do

to get rid of them is to,

well, clean up.