It doesn't matter if you watch a little TV or a lot of TV, dramas or comedies, network shows or Netflix, you've likely noticed a startling trend. An epidemic, if you will. Everyone (well, every woman) on TV has the same damn hair. The same straight-up-top, loose-curls-on-bottom hair.

This is the kind of hair that does not occur in nature. Natural waves are never this three-dimensional, and natural curls contain way fewer strands per spiral. This hair, this everywhere TV hair, is entirely artificial, heat tool-engineered for your viewing pleasure.

You don't see it in real life particularly often, and if you do, you think, "That girl's hair is really done." But on TV, it's the norm. Every female character regardless of role, age, or race has this hair. It's why your Hulu welcome screen may look like this:

Let's use Jane the Virgin as an example. Jane, the show's delightful protagonist, is seated in the middle next to her mom, Xiomara. They both have The Hair.

Petra, who has edged her way into A-story territory this season, has The Hair while laid up in the hospital. You know who else does? Her doctor! Who is an extra! With barely one line!

Here is The Hair on exceedingly boring secondary character Detective Susanna Barnett:

And here's The Hair on Dr. Bolton, who appears in exactly one episode of the show:

So many questions, but mostly: why? Also, when?

"Over the last couple of years, straight hair went out and embracing more of a curl or wave took over," says Cynthia Vanis, a hair department head for film and television who has worked for Younger, Law & Order: SVU, and Louie. "Also, it's so much more manageable with shooting. Straight hair moves a lot, and if one piece is out of place, you can totally tell. You can cheat easier when there's more movement within the hair."

Not only does it help with continuity, The Hair also makes shooting easier in other ways.

"It opens up the face," she continues. "You can have your hair down without it hanging directly over your eyes, which is the biggest criticism every director has: 'Can we get her hair out of her face?' You curl the hair back, and it's automatically opening up the face and especially the profile, which is the hardest thing to shoot on a woman with her hair down."

Looking good from all angles is important, whether you're a lowly publishing assistant who is secretly 40, like Liza on Younger...

...or an HBIC, like Cookie on Empire.

As Vanis explains, "It's super relatable and versatile. It's not specific — it works for people with shorter hair, with longer hair. TV lives in this world of sort-of-done, but sort-of-effortless looks. That's why they all have this hair. It's like, 'You could attain this at home, but I also look really polished and put together.'"

You could indeed attain this at home with a curling wand or even a creatively-employed flat iron, but you would run the risk of looking like a beauty pageant contestant and/or a (cool!) Texas mom.

"There's a little bit of fantasy that comes in on television because everything looks distorted from what it looks like to your normal eye," she says. "You might be like, 'Wow, that hair looks crazy, why is there so much height in the crown?' in person, and then you look on a camera screen and it's like, 'That looks normal.' There's a weird distortion that happens between fantasy life and real life, and you're bridging that gap between a relatable quality and looking presentable on TV."

Which is why you can have The Hair as the new girl on New Girl:

Or as a random pawn on How to Get Away With Murder:

And also when you're on the most perfect show on television:

Or its blatant, inferior ripoff:

The Hair: case closed.