Fly Metamorphosis Is a Beautiful Nightmare | Deep Look

Like the beloved butterfly, a house fly goes through an incredible metamorphosis. To make its grand entry into the world, it deploys a specialized, fluid-filled balloon on its head called the ptilinum (till-EYE-num) to break open its pupal casing, freeing itself to buzz around your kitchen.

DEEP LOOK is an ultra-HD (4K) short video series created by KQED San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Explore big scientific mysteries by going incredibly small.

House flies start out their lives as eggs. Maggots hatch from those eggs and eat (and eat and eat) until they’re ready to pupate and turn into flies. Emerging from their pupal home takes a lot of effort. In fact, they evolved a whole organ just to break free from that hard case. They use that organ, called a ptilinum, a pulsing sac filled with hemolymph – or bug blood – just once in their lives, to get out of their pupae.

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#deeplook

[PikaPetey]

im so glad insects are tiny cause they are horrifying up close. I love and hate Deep look everytime they post a video.

[vivi_tch]

"It's realized its full potential; to fly off into your house and drive you mad"
What a more true statement

[EldritchDoodler]

So what you’re telling me is, that weird gap on a fly’s face I’ve always been curious about is in fact the remnants of a blood-filled battering ram

[jimb.]

*"Fly Metamorphosis is a Beautiful Nightmare"*

Yes. Jeff Goldblum and David Cronenberg demonstrated that to me already....

[shardinalwind]

Goodness, the narrator has so much talent, they even manage to make the most hated pests seem cute

[youngspark]

Soo much effort and dedication just to annoy me while I'm eating my favorite donut

[evilferris]

Boy, did I pick a bad time to eat an overripe orange while watching science YouTube.

[dirt]

woah, i had no idea flies had to do that to get out, straight through the face?! for some reason knowing each house fly has a scar makes them cooler...! i love this channel!

[sablesaber]

"uuugh I'm going to my room"

Stop it 😭😂

[TonyTylerDraws]

Metamorphosis is such a weird, complex process

[zli]

Always hated flies but always been fascinated by their biology. Thanks for not ignoring the more common and annoying insects!

[MagicianFairy]

I knew flies had a pupal stage but never once have i ever seen it before. Wow. What a struggle to get out of it's former bean body.

[Duo_Fish]

The ptilinum is an ingenious temporary organ as it not only helps the fly to break open its pupae, but also gives it a place to move hemolymph from the rest of its body allowing it to slim down a bit to better squeeze its way out of its tight pupae. Other insects and arthropods have a myriad of different ways to escape their pupae and molted skin that vary from being able to wriggle tiny hairs covering their bodies to having enough segments that they can just ungulate to escape. Boy I'm glad we don't have exoskeletons to worry about.

[shelleyeatz]

That maggot “hi” 🤣🤣🤣 got a nice goosebumpy chuckle out of that

[gowokegobrokee]

Legitimately my favorite channel on YouTube and I’m 30!! The filming is impeccable, the narration is soothing and engaging. Just perfection all around well done deep look team!!

[octologue]

I honestly really like insects. They're so alien to us, sometimes in a gross way, but personally I think there is a quite beautiful aspect to it.

[StacheCam]

After being sick for 5 days I’m now okay enough to watch YouTube and today I learn how flys become flys

[mayurlagad]

As you try to understand nature more and more, you get mesmerized by its elegant beauty!!!

[TheWhiteScatterbug]

Flies are such underrated animals! They can look really funny or cute too! Big-headed flies (Pipunculidae) have heads that are basically just eyes and bee flies (Bombyliidae) are all fuzzy and adorable!

[deshawnglosson]

Y'all I never felt so grossed out and educated at the same time... everyone please stay safe and blessed much love from San Antonio...