Why Do We Have Such Crooked Teeth?

A lot of humans need or want braces to fix their crooked teeth, but why do you never see a dog walking down the street with headgear? Our ancient ancestors and mac and cheese may be to blame!

*Correction: Even though hyraxes look similar to rodents, they're actually in the order Hyracoidea, not Rodentia! They're more closely related to elephants and manatees than to mice and guinea pigs.*

Hosted by: Hank Green
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Uploaded by: SciShow

Views: 632154
Added: 2 months ago
Runtime: 2:58
Comments: 1492

Tags for this video:SciShow  science  Hank  Green  education  learn  teeth  hunter  gatherer  hunter-gatherer  human  biology  braces  animation  agriculture  early man  anthropology  skull  bone  food  cooking  dentist  jaw  chewing  evolution  genetics  development  developmental plasticity  pasta  meat  macaroni and cheese  vegetable  beaver  

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π_Rolπ_Rol (13 days ago)
This isn't always the case for some people. We also have to mention that skull shape is also important in this matter, people with flat skulls tend to have more space for their jaw than people with rounded skulls [by flat and round, I mean the way it looks from behind]. In some cases, the teeth might not even crook at all despite the diet of the person.

Peter van RynPeter van Ryn (14 days ago)
Yea. Mac n cheese. mmmmm

Victoria FamoriyoVictoria Famoriyo (15 days ago)
I like his shirt

Erwin SchrödingerErwin Schrödinger (16 days ago)
Since Kid I have my teeth so crooked that I'll replace them with implants.

frank Guanfrank Guan (16 days ago)
So vegans will more likely to have crooked teeth :)

Teeyah ArroyoTeeyah Arroyo (20 days ago)
I'll be wearing braces next week since my teeth aren't crooked although in the front area, I have three of my tooth below that are place onwards so my teeth are considered under bite. I am hoping that a normal brace will do a job, maybe I'll be wearing them more than 2 years. I am excited yet nervous. Love your vids! 🙏 FROM PHILIPPINES ❤

Ima DorkIma Dork (21 day ago)
Crooked teeth are so cute though. Anyone with me?

ShironShiron (14 days ago)
ew no

NoNameC68NoNameC68 (21 day ago)
I never got braces when growing up, so my teeth are a bit crooked. However, I also never had to get my wisdom teeth removed. I'm wondering if allowing my teeth to become a bit crooked gave my wisdom teeth room to come in.

Straight teeth are over rated.

AusintuneAusintune (21 day ago)
no?? crooked teeth??? fix your diet e.e

polyanthesispolyanthesis (21 day ago)
i never needed braces and still have my wisdom teeth, no crowding.

Littletwinkster AJLittletwinkster AJ (21 day ago)
You should see my dog's teeth..

GoogleHelpYouGoogleHelpYou (22 days ago)
So the reason we have wisdom teeth is not because of descent with modification, but rather we eat softer food?

joe4490joe4490 (24 days ago)
At the head of the episode you said people "need or want to have their teeth straightened". You answered part one but didn't get at part 2, the "want" part - which is that modern humans in certain cultures place a lot of emphasis on the visual appearance of teeth. The 'crooked teeth' of an American will often be perceived as normal teeth in many other parts of the world. This leads to a much higher emphasis in certain countries or cultural spheres on attaining a certain look or arrangement of teeth, which has little to no impact on comfort or functionality outside of societal perceptions. So perception of tooth crookedness is at least partly cultural, and not genetic OR plastic.

TheMysteriousUnicornFamiryTheMysteriousUnicornFamiry (24 days ago)
Lol there was an add about Dentist doctor Daniel Daniel :=

Amanda HydroAmanda Hydro (24 days ago)
I feel like a lot of people don't "need" braces, slightly crooked teeth aren't a medical problem.

PyroJohn19PyroJohn19 (25 days ago)
Hyraxs are not rodents!

Ayab41Ayab41 (26 days ago)
What about tooth gaps? I have them but im getting braces

Alice in OverwatchAlice in Overwatch (26 days ago)
i was born with 2 adult teeth missing (the 2 next to your front teeth) and 2 wisdom teeth down the bottom and none at the top............. now to be "aesthetically pleasing" i have to pay $10k... how tf is that fair... and that was after $8k my mum paid for bracers when i was growing up... should do a video on why dentist charge so much.

Bill ClodBill Clod (26 days ago)
It would be enough to have a toy to chew. We could keep the delicious food and have big jaws!

Born HaterBorn Hater (27 days ago)
My teeth is pretty straight already. I don't need braces.

Ryan GorsegnerRyan Gorsegner (27 days ago)
Does this mean if I chew gum a lot I don't have to get my wisdom teeth removed?

Kami ChanKami Chan (27 days ago)
braces are death

BigFatCornBigFatCorn (28 days ago)
Never been to the dentist never need to. My teeth are really good but my front teeth are slightly pointed outwards.

TomDelonge's FunnyPictureTomDelonge's FunnyPicture (28 days ago)
This video made my teeth go gray

Siddharth ChoudharySiddharth Choudhary (29 days ago)
girls with braces are super cute!

Sten saxpåseSten saxpåse (29 days ago)
Mewing helps with crooked teeth and wisedom teeth

Side Ponytail .GirlSide Ponytail .Girl (29 days ago)
Nobody in my family ate too much soft foods growing up (except for toddlers, naturally), I remember always biting in whole carrots and apples as snacks, thus nobody in my family ever needed braces. However, my perfectly straight teeth started getting crooked once all four of my wisdom teeth came in. They just pushed them around a little. So annoying.

you-are-the-pelican-manyou-are-the-pelican-man (29 days ago)
my teeth are not crooked why are you telling me they are.

dallen3000dallen3000 (1 month ago)
could this be a reason why small kids chew on things, because they subconsciously want to make their teeth stronger?

Cornhole JacksonCornhole Jackson (1 month ago)
so like if i have a kid i just have to feed it lots of tree bark.

BushDid9/11BushDid9/11 (1 month ago)
I wanted to brag about my naturally straight strong healthy teeth but i have a feeling my wisdom teeth, grinding, and tmj are going to eventually start biting me in the ass for it 😂

A Fucking Human BeingA Fucking Human Being (1 month ago)
lol brush ur fucking teeth so you won't wear braces they're nasty

Max DumontMax Dumont (1 month ago)
can you do my Honors Biology Homework Hank?

SCdreamdrawerSCdreamdrawer (1 month ago)
Now I wonder how your jaw and teeth would be affected if you were raised on an all liquid diet like Soylent or Queal.

KingCamembertKingCamembert (1 month ago)
Could chewing gum and such increase jaw size during growing up? I mean it uses 'intense chewing power' after time.

Gabriela BarrientosGabriela Barrientos (1 month ago)
"Our jaws SHRANK"????? isn't it supposed to be "our jaws SHRUNK"?

BeatDroppingBeatsBeatDroppingBeats (1 month ago)
why can't life befair tome

Tate HendricksTate Hendricks (1 month ago)
Is anybody watching this, while we don't have crooked teeth?

Brasley BakszaBrasley Baksza (1 month ago)
Disagree. That only accounts for crowding teeth, not funky ass yuck-mouth. Jaw length and breadth varies across humans and there are populations that have higher frequency of nice teeth despite little variation in jaw:tooth size ratio.
Two conclusions: Straight teeth aren't being selected for and do more thorough research.

the memer of dankthe memer of dank (1 month ago)
im gonna need a gesher soon

Whitney SkyesWhitney Skyes (1 month ago)
I have never had braces and my teeth are almost perfect.

Hector PachecoHector Pacheco (1 month ago)
if you're Christian, then none of this applies

PhoenixPhoenix (1 month ago)
Haha,I got perfect teeth fuckers!

Samus KerriganSamus Kerrigan (1 month ago)
chewing intensifies

GlitchGaming45GlitchGaming45 (1 month ago)
Damn oreos gave me cavities

Marnie PabloMarnie Pablo (1 month ago)
Scishow why do we have stretch marks and how can we get rid of it pls a video about it.

BacchanaliaBacchanalia (1 month ago)
My teeth are biologically perfect.

Ano N. YmousAno N. Ymous (1 month ago)
2:36 'Thank you for asking and thank you especially to Oliver Patreons' jk

TheCraftingCatTheCraftingCat (1 month ago)
But are they bad? My teeth are very crooked, so my mom and the dentist are saying that I need braces. But I don't want them, I like my teeth how they are. So is it a serious problem?

Jennifer DallyJennifer Dally (1 month ago)
If they are so crooked that you can't properly clean all of them, then braces should be seriously considered, but if you can clean them correctly then it isn't as much of a necessity. You should also take into account of how old you are, if you're still in elementary or middle school, then your jaw may not have fully grown so your teeth may straiten out at least a little bit.

bandit957bandit957 (1 month ago)
Why do we all have crooked teeth? Because we're just so cool, and only cool people are allowed to have crooked teeth.

Vanessa G.Vanessa G. (1 month ago)
I've always had perfectly straight teeth since my permanent ones grew in without the use of braces or any of those other straightening methods, guess I'm just lucky 🤷🏻‍♀️ can't help but to flaunt my smile lol

Jaeger The GreatJaeger The Great (1 month ago)
My family actually has a history of being born without certain teeth, like my sister only had 3 wisdom teeth.

watts300watts300 (1 month ago)
Completely off-topic, but a still a tangent from the video -- do other cultures in the world (eastern Asia included) also enjoy macaroni and cheese as much as we Americans do?

Jennifer DallyJennifer Dally (1 month ago)
From my experience, many people from those cultures do like it when they have it, but they don't have it super frequently (mac and cheese is a ridiculously American/North American thing).

science ki vinesscience ki vines (1 month ago)
why are my teeth above jaw line? can it be fixed(above another teeth)

Nemo FilNemo Fil (2 months ago)
first of all, human jaws shrank way before the agriculture revolution happened thanks to fire and cooking meat, which allowed the the brain to get bigger in expence of the jaws. agriculture may have further shrank jaws a little bit.
but more importantly, hyraxes aren't rodent!!!! from all people i expected you hank to know this!

Geflügel HNZGeflügel HNZ (2 months ago)
Especially if it got maggot cheese!

Peter mGPeter mG (2 months ago)
Mac n cheese is like soup to me

coolsarahkry1coolsarahkry1 (2 months ago)
I love your shirt. It's...hypnotizing...

Chapter ElevenChapter Eleven (2 months ago)
so i want to get braces, cause my teeth are all messed up. or invisiline. something to fix em, yknow? but i dont want to do that until my wisdom teeth come in, since i dont wanna spend a bunch of money to get braces then have my wisdom teeth come in and fuck them all up again.
however, as far as i know, my wisdom teeth could take until im 27 to come in (thats how old my mom was when hers came in; my dad got his cut out quite painfully before they came in). if i even have wisdom teeth. do I have wisdom teeth? who knows. I havent been to a dentist in years, either.
...my teeth deserve a better host.

iicharliieii 2142iicharliieii 2142 (2 months ago)
My teeth are strange, they're straight (I've never needed braces) but they're misaligned.
My canine hangs over the first premolar one one side, and the other hangs halfway between the lower canine and first premolar.
And some of my teeth can't touch their counterpart or whatever's directly below.
It doesn't feel right, but it's never caused me problems...

David SalleyDavid Salley (2 months ago)
Your videos are very interesting, but I have and 8 AM class, so I need to go to sleep so I can work on homework for another class during that time.

Courtney CourteauCourtney Courteau (2 months ago)
I could've gotten braces but I chose not to.

Sanjuan GuestsrSanjuan Guestsr (2 months ago)
Hank's the best

Feynstein 100Feynstein 100 (2 months ago)
My canines are slightly bigger than the rest of my teeth. Was I meant to be a vampire?

IsaacSnider DoesThisOneThingIsaacSnider DoesThisOneThing (2 months ago)
Wow that shirt

eustagoesouteustagoesout (2 months ago)
blame it on the weather

M JenciM Jenci (2 months ago)
I have no wisdom teeth and in addition to that are missing three adult teeth, I still have 3 baby teeth past my 20's.... My dentist say's I'm lucky I'm missing so many teeth because my jaw is super small and they wouldn't have fit anyway, just have to be careful because those baby teeth aren't meant to last a lifetime.

MrAstronomer 22MrAstronomer 22 (2 months ago)
Please do a video on TMJ and Teeth grinding.

JBTechConJBTechCon (2 months ago)
It's actually miscegenation. If you cross-breed an ethnicity with big teeth to an ethnicity with small mouths, you get kids with crowded mouths. Same reason there are so many C-sections.

TomatoHeadGaming ­TomatoHeadGaming ­ (2 months ago)
why was I born without wisdom teeth (and also missing my upper canines)

Anujan KirupakaranAnujan Kirupakaran (2 months ago)
I'm hoping I don't get braces coz my younger sister has them and they look painful

TheMonsterAbyssTheMonsterAbyss (2 months ago)
Lol, i was searching for Papa Roach's song and I find this...

Rebecca LopezRebecca Lopez (2 months ago)
Pics would have been nice but I still learned a lot

crossfire367crossfire367 (2 months ago)
I'm pretty sure Dentists aren't all that woeful when they get to bill us for all the braces work....

gigantkraniongigantkranion (2 months ago)
"It's hard to test directly in humans though, because that would mean limiting what people could eat for a huge chuck of their lives."

"Chewing your foods forever till your teeth break"

Umm... Chewing gum?

Preferably, a really tough kind.

Damian the PhoenixDamian the Phoenix (2 months ago)
Damnit, Hank....now I have a craving for mac and cheese

NintendoPoliticsNintendoPolitics (2 months ago)
I always wondered why humans are the only creature that cannot drink directly from the water source...why do we have to clean our water to drink it?

Shaz _Shaz _ (2 months ago)
Because you will die from either toxins or bacterias. You can't find a clean water source in most areas anymore. Modern human body simply doesn't have the tools to deal with those anymore. Apparently bottled spring water suffices? You can drink that, and you can drink from clean sources.

Hortonius ImperialusHortonius Imperialus (2 months ago)
uh, but it can be demonstrated in humans.. Do you know how archaeologists can identify bones of archers, esp from medieval times, and English long-bowmen in particular? Or how they can identify those bones belonging to a viking seafarer? it has to do with their professions and how their bones responded to stress

ccggenius12ccggenius12 (2 months ago)
So, if I raise my kid on a diet of beef jerky and raw vegetables, I'll be less likely to need to drop cash for braces?

MinecraftCats CatMinecraftCats Cat (2 months ago)
I hate braces no one likes them, I have braces them WHAT NO MAC AND CHEESE that's what they SAY TO EAT DUMBO

Socks, shoes, and hatsSocks, shoes, and hats (2 months ago)
Wait... aren't hyraxes related to elephants and manatees, not rabbits and rodents?

atlastpeaceatlastpeace (2 months ago)
I got braces out of vanity. However, it did give me a few health benefits: easier flossing and brushing, also it's impossible to bite my nails now.

Fern MooreFern Moore (2 months ago)
So does that mean we should be making our kids eat raw food until their mouths are fully formed? Then we won't have to pay for expensive dentistry. lol

Johey JonssonJohey Jonsson (2 months ago)
My teeth are the product of some very fortunate genetics. Apart from one tooth I damaged when I ran my bike into a lamp post and one tooth I damaged by breaking it on a stroller at 11 months, making the second tooth come in slightly tilted, all my teeth are straight. Not even my wisdom teeth came in crooked, which in itself is a miracle.

Adam XyzAdam Xyz (2 months ago)
The real reason you're teeth are Crooked is because your jaws aren't developing properly. This means your jaw is too small for what it is supposed to be. This means your mouth posture is wrong. The good mouth posture requires your tongue to be pressed up to the roof of your mouth at all times when not eating in order for your jaw to develop properly from the tongue pressure.

Look up Dr Mike Mew

yoyomomishungryzyoyomomishungryz (2 months ago)
Some dogs have crooked teeth

SPACKlickSPACKlick (2 months ago)
Hyraxes aren't rodents, they're the closest living cousin to the tethytherians (Elephant, manatee and dugong). Very different beasties than rodents.

funmbimotifunmbimoti (2 months ago)
speak for y'all selves....my teeth are perfectly straight.....

Frank TufanoFrank Tufano (2 months ago)
Its not solely agriculture; they are plenty of people born with straight teeth in our generation. If you look at Weston A. Prices research on dental caries there were civilizations less than 100 years ago with jaws wide enough to accommodate teeth. The singer Pia Mia is a good example of someone with this jaw.

How can you say mastication has anything to do with bone and jaw development when babies were breastfed and our ancestors, at least during development periods, did not eat foods that required any more chewing now.

I know for certain being breast fed over formula fed plays a huge factor. You can also argue from that point of view that nutrient consumption of the mother during pre natal periods is important. Nutrient intake during early childhood into teenage years also plays a role but not nearly as much as the former.

Rin TohsakaRin Tohsaka (2 months ago)
My teeth are straight. I get asked whether or not I have have braces before, but I never did. My jaw just got wider as I got older.

Angel DiazAngel Diaz (2 months ago)
i never had crooked teeth. never needed braces. #blessed

Melissa NehrMelissa Nehr (2 months ago)
Removed my wisdom teeth under the belief it would prevent my crowding. It didn't =_= adult braces anyone?

Bendy the Dancing demonBendy the Dancing demon (2 months ago)

Casey MonaghanCasey Monaghan (2 months ago)
but steak is really chewy...

stay safestay safe (2 months ago)
Improper oral posture is a big culprit.

Teeth together and tongue on the roof of the mouth. Mike Mew has talked about this a lot.

Chris EastChris East (2 months ago)
There is a breakthrough in orthodontics called Orthotropics, the Man behind it Dr Mike Mew has some very convincing evidence that a big factor in crowded teeth and under developed jaws may be due to not only a soft diet but also the position of the tongue in the mouth and swallowing habits as well as mouth breathing. I would LOVE to see Sci show do something with him hes an amazing guy.

Cameron JohnsonCameron Johnson (2 months ago)
I feel bad for most people, i've never had any problems with teeth. all mine are straight and "perfect" fitting

Lovell MillsLovell Mills (2 months ago)
Who else is here because they have Braces!?

What the fuck do you mean by, "we?"

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