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Why Do We Smile?

Why Do We Smile?

3 күн мурун

The Viruses That Shaped Humanity
Why Skin Creams Give You Rashes
When Two Species Mix

When Two Species Mix

13 күн мурун

These Fish Eat Scales

These Fish Eat Scales

16 күн мурун

All This Noise Is KILLING Me!
How Antarctica Froze Over
The Curious Case of Colic
The Oldest Shipwreck in the World
The Male Biological Clock

The Male Biological Clock

2 ай мурун

Poor, Misunderstood Poison Ivy
I Can't Believe It's Not Wood
Why Do Humans Like to Get High?
How Big Can Black Holes Grow?
Firehawks: Nature's Arsonists
The Real Story of John Snow
Do You Need 10,000 Steps a Day?
  1. Ada H

    Ada HСаат мурун

    Dont mind me being a curious 13 year old

  2. Jon

    JonСаат мурун

    A very good tip for the burgeoning psychopaths out there. Just smile even though you are wearing aviator glasses and the sweater your dead mother knit for you 28 years ago. Humans are very easy creatures to be manipulated by a select few expressions you can master to put them at ease. Follow social norms and they will never suspect a thing.

  3. Keith Birchall

    Keith BirchallСаат мурун

    When sex is hard ? Is that not marriage

  4. Noble4Truths

    Noble4Truths2 саат мурун

    But I rarely smile

  5. Spencer Chase

    Spencer Chase2 саат мурун

    Biological cells don’t seem like robots... it just seems like you’re calling them the wrong thing. Misleading video...

  6. Møíšęş Ğōňżälëž

    Møíšęş Ğōňżälëž2 саат мурун

    Crystal meth?

  7. a

    a2 саат мурун

    :( Am I doing it right?

  8. ChestNautPlays

    ChestNautPlays2 саат мурун


  9. María Martínez

    María Martínez2 саат мурун

    Why people born blind smile?

  10. S A

    S A2 саат мурун

    We just need a new herv update

  11. Raja Khan

    Raja Khan2 саат мурун

    No i don't think we're actually showing off smiling.. . . . Because.. We also smile/laugh when we are alone.

  12. paperhabit

    paperhabit2 саат мурун

    I remember watching a documentary-type thing when I was like 10 (so I don’t know how valid or scientific it is), but it briefly explained human smiling as a behaviour that emerged from hostile teeth baring when our ancestors became more social: Imagine a human ancestor startled by a sudden noise and baring their teeth as a threat to the potential threat. When the source of the noise turns out to be another individual of their species, perhaps from the same social group, the bared teeth could come across as aggression and the first individual could be met with hostility from the others. By changing the teeth-baring into a more friendly gesture, the first individual could avoid the unintended aggression. The smile thus could have come about as a redirecting/repurpose of the initial teeth-baring to friendly faces. Again, not sure how legit this explanation is, and it could’ve just been an unverified hypothesis. Don’t even remember the name of the tv show or documentary or whatever it was. But anyway, thoughts?

  13. Mother of Chaos

    Mother of Chaos2 саат мурун

    Curare, potassium chloride...

  14. DashedEuthanasia

    DashedEuthanasia2 саат мурун

    Okay, but why do we smile uncontrollably when something really amusing has just happened? Or when we're experiencing something enjoyable, even when alone?

  15. Kazuya Muhid

    Kazuya Muhid2 саат мурун

    *samalas eruption has joined the chat*

  16. Rautik Doshi

    Rautik Doshi2 саат мурун


  17. Mark Botirius

    Mark Botirius2 саат мурун

    Thumbs down for not showing a single example. Shame on you

  18. avega2792

    avega27922 саат мурун

    On a road trip last summer I stopped in Gallup New Mexico for breakfast. Come to find out later that there was a uranium spill at Church rock just north of Gallup in 1979, the largest uranium spill in the US to date. The whole thing was abandoned and swept under the rug because the people that were affected most were low income families consisting of mostly minorities like hispanic and native Americans. There weren’t any substantial clean up efforts made for decades after the spill, and after the company running the site was allowed to close up shop and skip town. The Church rock spill is the biggest radioactive disaster in recorded US history, even bigger than 3 mile Island, and hardly anybody knows about it.

  19. W B C

    W B C2 саат мурун

    Study a full day, watch for six minutes, get immediately pumped again.

  20. Kristina Savic

    Kristina Savic2 саат мурун

    I’m a regular plasma donor 🩸 so I need to have high levels of iron & antioxidants! Love eating healthy

  21. Samantha Khan

    Samantha Khan2 саат мурун

    Why do we smile? To make ppl trust us or view us as non-dangerous... how did it actually become that signal??... brain wiring I guess...

  22. arya yudha

    arya yudha2 саат мурун

    0:38 "Back of if you don't want these to go inside of you!" 😳😳😳

  23. Henry Newcomer

    Henry Newcomer2 саат мурун

    Relating back to the idea that the exposure of teeth encourages suppression: would it not seem feasible that the new target/subject then uses that same learned trait to it's own advantage towards others, thereby encouraging a social hierarchy, hence "relationships" / "friendships?"

  24. sad potato

    sad potato2 саат мурун

    Can you talk about how mental illnesses affect one's sex life or lack of. Like how some people with bipolar have a higher sex drive and people with major depression have little to none.

  25. Kyle Pan

    Kyle Pan3 саат мурун

    This guy just seems like that nerd in school

  26. Sr. Wingtiger

    Sr. Wingtiger3 саат мурун

    Finally my coffee machine can give concent

  27. 01Phenom

    01Phenom3 саат мурун

    that fupa is getting huge

  28. Peizxcv

    Peizxcv3 саат мурун

    Because primates show weakness smiling

  29. Springtrap

    Springtrap3 саат мурун

    You should probably try working out the cure for breastfeeding cancer before. It's such a high count.

  30. B.B.R 1010

    B.B.R 10103 саат мурун

    He planted the trees to claim the land. At the time if you planted a tree on unclaimed land it was yours. He did it all to resell the land.

  31. Obverse Singularity

    Obverse Singularity3 саат мурун

    Thought the Mariana trench was the deepest. But hit me with the numbers. You mean deep relative to surface not sea level.

  32. __

    __3 саат мурун

    Quit sht stabbing then

  33. Lizzy Long Neck

    Lizzy Long Neck3 саат мурун


  34. Dana Coleman

    Dana Coleman3 саат мурун

    Here's my theory: physicists touch themselves... A lot! Or not at all... Or both. Yeah, I think I'm going to go with a lot.

  35. peekeyeseek

    peekeyeseek3 саат мурун

    Hi. How about an update?

  36. Bambino Jordanie

    Bambino Jordanie3 саат мурун

    See signs if u into rb ligne

  37. Samwise Gamgee

    Samwise Gamgee3 саат мурун

    I dont know about this. I don’t doubt that it kills brain cells. But so do a lot of things like alcohol for example

  38. Nolan Orion

    Nolan Orion3 саат мурун

    *looks at the Oleander in my garden* ... They're just pretty to look at officer I swear.

  39. Emoboy Emoguy

    Emoboy Emoguy3 саат мурун

    are you calling me an animal?

  40. Bill Boyd

    Bill Boyd3 саат мурун

    The US national debt is the deepest hole in the world, and they are still digging!

  41. DrSharkBoy

    DrSharkBoy3 саат мурун

    So we got pillar flies and might be on our way to artificially made but biological waifus? I love the future.

  42. Submersed24

    Submersed243 саат мурун

    I have crazy anxiety and high blood pressure, but I am only 23 and my heart is fine from what my dr told me. She prescribed me this instead of a diuretic, but I have been nervous to start it because I have been worried about long term effects. This is great!

  43. sprobgik

    sprobgik3 саат мурун

    so we can make living slaves without using alot of mechanical parts?

  44. Luke E

    Luke E3 саат мурун

    I think “degeneration of human sexuality” would be a far more accurate title.

  45. Mike Simonian

    Mike Simonian3 саат мурун

    The undisputed truth. Smiling Faces Sometimes

  46. Domhnall MacLean

    Domhnall MacLean3 саат мурун

    So I get a blocked nose through something I can't really control?... Great.

  47. DuckTheCat ASMR

    DuckTheCat ASMR4 саат мурун

    Judge me if you want but parasites fascinate me Even ones that aren’t real I.e headcrabs and face huggers

  48. Paige Choi

    Paige Choi4 саат мурун

    Oh, my. HANK!!!!!!

  49. Mike Roberti

    Mike Roberti4 саат мурун

    What TH is a “Clade?”

  50. TekaiGuy

    TekaiGuy4 саат мурун

    SciShow today: Why do we smile? SciShow tomorrow: Why even get out of bed?

  51. Mike Roberti

    Mike Roberti4 саат мурун

    What about a smirk?

  52. sergent popoy

    sergent popoy4 саат мурун

    Iam eating bunt toast while watching

  53. TheRedBug

    TheRedBug4 саат мурун

    "Phantom buzz says a lot about your mental health" My mental health must be perfect, my phone never phantom vibrates, it instead talks to me about its daily life

  54. Mohanad Mofeed

    Mohanad Mofeed4 саат мурун

    The prophet Mohamed said it 1400 years ago. very nice and interesting video thx❤

  55. Stars at Night

    Stars at Night4 саат мурун

    I’m writing a book. A character who had wings gets them publicly cut off the day before her execution as a form of humiliation and dishonor (wings are a huge status symbol) they do stop the bleeding (she needs to fester in her shame as part of her punishment) but is saved by here friend. She is then thrown into a river. She ends up with a group of people and I’m trying to find a way to keep her back from getting infected, (dirty cell, dirty blade, dirty river) the people scrub the wound clean with soap and water but I needed something else, asked my grandma and science teacher what they thought and they both said honey, now I am doing research on it. This stuff truly seems to be magic.

  56. Camila ,

    Camila ,4 саат мурун

    "cooperative smile" sounds very Desert Bluffs-ey to me tbh

  57. Big Mike

    Big Mike4 саат мурун

    I'm in my mid-thirties and I cannot smile on command without looking creepy. I don't think people find it agreeable.

  58. Life with Murph

    Life with Murph4 саат мурун

    Why do you assume everyone smiles

  59. Josh James

    Josh James4 саат мурун

    Us smiling to show teeth seems oddly similar to the way dogs have a "submissive grin." I wonder if they're related

  60. Hannah Kay

    Hannah Kay4 саат мурун

    We smile because of frogs,

  61. Tomas Neshoba.holba

    Tomas Neshoba.holba4 саат мурун

    White people and black people don't have that DNA

  62. Antti

    Antti4 саат мурун

    *Frantically googlin Sestrin Supplements intensify"

  63. Limerence

    Limerence4 саат мурун

    Circuluniary rhythms could explain why women's periods on average are on a 29 day cycle when the moon is also on a 29 day cycle. Obviously not every women get's their period on the full moon and not every woman has a 29 day menstrual cycle, it's just the average. But if you remove a woman's sense of time (take away all natural time tellers, clocks, sunlight, etc) her period will be thrown off so your natural body clock could use the phases of the moon to know when to do menstrual stuff. I don't know about the chimpanzees, maybe they just don't notice the moon or count in days instead.

  64. n o c d l e s

    n o c d l e s5 саат мурун

    I’m crying. it burns.

  65. dan buell

    dan buell5 саат мурун

    #7 , me, when a fly gets in and I cant go to sleep till its dead

  66. Penname Bear

    Penname Bear5 саат мурун

    So thats why moving from the tropics to australia made me get nosebleeds.

  67. Shadowstray

    Shadowstray5 саат мурун

    I forgot how this was a thing. Haven't been carrying a phone on me for many years now.

  68. Movie_addict76

    Movie_addict765 саат мурун

    Minutes after drinking coffee .. no.

  69. Hridoy Govinda Das

    Hridoy Govinda Das5 саат мурун

    B12 is the only thing you need to supplement. Not even mentioned in this video 👎

  70. Gyrre

    Gyrre5 саат мурун

    So, Bicentennial Man?

  71. Thyepiccat !¡!

    Thyepiccat !¡!5 саат мурун

    But I don't smile

  72. Ainars Kalnins

    Ainars Kalnins5 саат мурун

    I smile to scare others away. It usually works.

  73. Sean Hannan

    Sean Hannan5 саат мурун

    What about creepy smiles though? Or fake ones that are meant to give social cues to the group while signalling out a target for an isolated emotion the idea being while the recipient feels under threat the subject can deflect this with support from the social group, those who were not direct recipients but were given enough information to recall the subject smiling. The information between the group and the recipient were different and thus you have a form of emotional isolation from a fake smile. As for creepy smile it's kind of the same thing just the emotion behind the smile being different, usually one that displaying a wish to harm the other person while masked under the guise of cooperation. My inability to put the words together of what I am talking about doesn't entail I don't know what I am saying.

  74. Ps4 all the way

    Ps4 all the way5 саат мурун

    Wait this story was real

  75. Ratchet

    Ratchet5 саат мурун

    Why do I like big butts?

  76. Cai Copley

    Cai Copley5 саат мурун

    Could American scientists be thinking this because our society and culture pressures us to smile all the time, and frowns upon us who don't?

  77. Lee Pemberton

    Lee Pemberton5 саат мурун

    "I am smiling!" - Black Dynamite

  78. Mithouna Phanoraj

    Mithouna Phanoraj5 саат мурун

    Really puts into perspective what sexists are trying to do when they tell you to smile.

  79. Najwa Laylah

    Najwa Laylah5 саат мурун

    I smile when I otherwise feel like it, but not when I'm nervous (training). Though well-aware that some people don't like to be smiled at, well, that's just tough for them.

  80. Chris2008

    Chris20085 саат мурун

    I am married. I have no reason to smile.

  81. Willian Dalsoto

    Willian Dalsoto5 саат мурун

    cause I pretend to be happy

  82. Gin M

    Gin M5 саат мурун


  83. paul harmer

    paul harmer5 саат мурун

    Being a frog really sucks

  84. Eduard Qualls

    Eduard Qualls5 саат мурун

    When someone British, European or other says something snarky about the "customary" system (it's called "imperial" _only_ when referencing the British version specifically) I have to ask them how the deuce they ever cope with a clock or a calendar. *_ It seems that a measurement system, like sexuality, is unnatural to some people only if it doesn't apply to them, personally. _* Obviously, these metric-oholics have been eating too many bananas, and couldn't hit a barn with a barley corn.

  85. Yiglic Persfactious

    Yiglic Persfactious5 саат мурун

    Sestrins could be useful for long term space flight.

  86. Ashan Ariyawansa

    Ashan Ariyawansa5 саат мурун

    Couldn’t the queen unknight the guy after the collapse?

  87. Shank Adams

    Shank Adams5 саат мурун


  88. Marcus Cornwall

    Marcus Cornwall5 саат мурун

    Its interesting how they assume these computer models and reconstructions are for certain the way the moai were created. As far as it makes sense to me thats just the only way they could figure out themselves but they dont know for certain thats how it was done.m.

  89. W Peter Campbell

    W Peter Campbell6 саат мурун

    Occasionally, hypothesis can lead to finding of facts. It is a rare event. The problem with hypothesis, however, lies with the individual or group construct of what to do or think with the application of such knowledge, which may or, more often, may not, produce the desired effect.

  90. Сашко Дмитренко

    Сашко Дмитренко6 саат мурун

    I don`t smile.

  91. Lotopi

    Lotopi6 саат мурун

    I have a habit of smiling a big toothy grin in situations that don't call for it, which makes it seem more awkward than inviting. Nervous, afraid, awkward, almost anything. What's worse about it is that I don't have a good smile.

  92. Rick Harold

    Rick Harold6 саат мурун


  93. Pup314

    Pup3146 саат мурун

    So why do we and some primates yawn? Why does seeing others yawn cause us to yawn, even partially seen yawns. Even hearing or reading the word Yawn can cause us to yawn. So are you yawning yet?

  94. Daniel Shao

    Daniel Shao6 саат мурун

    So basically smiling is largely social. Maybe that's why babies don't smile?

  95. pwestan oggg

    pwestan oggg6 саат мурун

    Your fingers are purple and that’s what your worried about..? -face palm- it’s a joke if u did not know :)

  96. Fawriel

    Fawriel6 саат мурун

    It always bugs me when people focus on the "showing teeth" part of smiling. I feel like the more important aspect is that a genuine smile reaches the eyes and makes them go half-lidded. Hence why you can see a ^^ and interpret it as a smile even though it lacks a mouth altogether. And I think that perfectly explains why smiling is friendly -- it shows that you're relaxed enough to drop your guard around someone. Like a cat slowly blinking, or even a lion approaching a watering hole and yawning to show that it doesn't intend to hunt. The latter even shows teeth as well, but that's incidental to the relaxed display of meaning no harm and expecting no harm.

  97. Robert Costello

    Robert Costello6 саат мурун

    The only reason I smile is because of the 45th President of the United States, Donald J Trump. Remember to vote in November for the one man that cares about America and its citizens. #AmericaFirst

  98. Man in Town

    Man in Town6 саат мурун

    Evolution theory is lie

  99. Gacha Kat

    Gacha Kat6 саат мурун

    To step in it or not to step in it, that is the question...

  100. 48Boltz

    48Boltz6 саат мурун

    I yawned like five times while watching the last 4 minutes.