Why Does Hair Grow The Way It Does?
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- Опубліковано 1 тра 2017
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Check out more of my friend Kyle’s sweet hair on his channel “Because Science”: • Because Science with K...
All mammals have hair at some point in their lives, but none of them wear it quite like humans. Why does our hair grow where it does, and not grow where it doesn’t? How does our hair get its color? And why does it go gray and often fall out when we get older and go bald? Learn all about the science of human hair in this week’s video!
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REFERENCES:
Harding RM, Healy E, Ray AJ, et al. Evidence for Variable Selective Pressures at MC1R. American Journal of Human Genetics. 2000;66(4):1351-1361.
Randall, Valerie Anne. "Androgens and hair growth." Dermatologic therapy 21.5 (2008): 314-328.
Yablon, J. "What is the latest theory of why humans lost their body hair?." SCIENTIFIC AMERICAN 297.3 (2007): 124-124.
APA
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It’s Okay To Be Smart is hosted by Joe Hanson, Ph.D.
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Writer: Sarah Keartes
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PS - Part 3 and 4 of our human ancestry series will continue next week!
Yay!
It's Okay To Be Smart yay thx
after that, can you make a video about how bad breathing in smoke from smokers next to you is?? I am quite interested in seeing how bad it is since my nightbours smoke like 24/7 and the smoke of them is getting into my room if I have my window open.
Harley .G UA-cam only lets you thumbs up a comment once, but just know I have more for ya.
***** either the darker eumelanin will overwhelm the color, or it produces auburn tones.
you can almost say the way your hair grows depends on your hairitage
mmhmm yes, I approve
It's Okay To Be Smart how dare you partake in such evil
It's Okay To Be Smart Your Facts are good but your face is as annoying like sleepers..😋
stop the planet, I want to get off
@@Kevin-um1nq what kinda evil would you prefer, silent bob?
PBS Studios? I bet the PBS stands for Pun Based Science
+
Exactly
no its a chanel called pbs
It stands for pubis!
Yep
Guys: History
Girls: Herstory
Joe: *_h a i r s t o r y_*
100th liker baby
OMGALUL
This is underrated😂😂
Lost a couple hairs while watching this.
*help*
Are you a bot?
I am C3PO, human cyborg relations.
cut it guys
@@AbudBakri human/cyborg, all male, sexual relations
From an evolutionary standpoint, it seems we kept the hair on our heads despite losing it almost everywhere else because hair is a good indication of health. Most dermatologists will tell you the best treatment for hair is eating well. So people with good hair attracted mates and passed the traits on.
Very cool video. Great to learn why the carpet doesn't always match the drapes -- just wish we didn't watch it during lunch (very vivid pubic lice animation).
L
This was great! I'm a hairdresser and it's lovely to see the topic presented. Did you know that all natural redheads have greenish ashy color to their hair? That's why it's difficult to artificially create a "natural" redhead.
In old-school color photographs and on not terrific color television pictures, redheads often seemed to have a sort of dull green patina to their hair rather than a copper or bronze gleam. I had auburn hair that frequently appeared muddy and greenish in photographs. Now you have explained why.
That’s so interesting!!
Quite interesting!
"That's why the carpet doesn't always match the drapes" LMAO 😂😂😂😂😂😂😂
Sure, the science is interesting, but think you can beat my hair puns? Go ahead and try!
Wait the video was released 30 seconds ago and your comment is 32 minutes old
What?!
It's Okay To Be Smart you really missed a pun with the rock at the end. still a great video though!
Daksh Joshi - you can upload to private first
I would tell some chemistry puns, but all the good ones argon.
Also don't believe atoms, they make up everything.
4:14 A bald scientist figuring out how to stop hair loss... Haha
😁😁😂 I guess need is the mother of invention 😉👍
Haha.. Didn't notice that while watching the video
You didn't really answer the question in the title.
He touched on it for a bit
Didn't answer at all! I'm really puzzled about how long hair can be beneficial to us in any way. Why doesn't it just stop growing at a certain lengh like our eyebrows or pubic hair? Same for our fingernails - if you don't cut them they become curly and disturb the functioning of your hands alltogether.
It helped finding a mate such as male peacocks dont have any survival advantages having long as, fabulous feathers. Thats just a guess, though.
Yes they did ... pay attention!
Still interesting. But yea... To me, it was more about ' Why does the hair on our heads grow indefinitely?'. So I just googled it afterwards... haha
0:28 - Oh thank goodness. I was about to wig out.
One of the best Science UA-cam Channel's ever! Keep posting. Stay Curious. Cheers from a Brazilian Fan
Why is my last name so popular in Brazil?
@@Sergio-fu7mv Because one of your ancestors couldn't keep it in his pants.
@@lonestarr1490 Lmao
Is it just me bad his puns are so bad they’re actually hilarious?! Oh my god I love this guy
sooo it's a hairy situation?
I love your videos! Not to long, not to short, just right! And so informative and interesting! I freaking love it! Please keep pumping them out! I'm your number one fan!
Doctor, Doctor! My hairs falling out, Can you give me something to keep it in?
Sure! Here's a shoe box!
Cmon man step up your game you only told us why about pit hair you didn't say why we have head hair or pubes and you didn't say why we don't have hair in others places (except when you made the slight mention of "maybe we got rid of some to shed heat" and that's as far as you went...)
I downvoted for this ^ reason
Hair is portable shade, protects us against sunburn. We stand upright, so long hair on our head gives most of the body cover. Pubes protect the more sensitive areas. We got rid of the rest because we evolved in africa and it was hot enough already.
I think pubes are to prevent friction during sex,and on women they actually prevent harmful bacteria from going in the vagina.
I also wanted to know why our hair doesn’t stop growing at a certain length in some places but not others. Example, why does the hair on your arm only grow so long but hair on your hair doesn’t stop growing
It's because we don't really know lol... I think that he's just trying to strike up the conversation.
Thank you so much for uploading this video. It is helping me get through the pandemic!
I love watching your videos full of unique knowledge I can't get any where except here
You didn't really answer why, I feel like a lot more could be said for another video.
ua-cam.com/video/rf6BnOLb5xs/v-deo.html
here's a way better video about this
Thirsty Leaf That video doesn’t answer the question either. It just explain how hair grows
The interesting questions are:
- Why did we lose most hair when we became human?
- Why _didn't_ we lose head hair & pubic hair?
Bonus:
- Why do some male people grow beards while others don't?
@@cube2fox In order of appearance:
- We didn't. As said in the video, we still have about the same amount of follicles we always had. It's just not growing into dense fur anymore, probably due to evolutionary advantages this change yields. Sweat works best without fur.
- Because losing head hair didn't yield the same advantage. Plus head hair protects your brain from UV radiation to some extent, while pubic hair helps holding your scent presumably making you more attractive to the other sex (in the olden days).
- Genetics. And yeah, it bothers me as well.
@@lonestarr1490 That's a good attempt. Of course we lost the fur because this was advantageous. Otherwise we wouldn't have lost it. But why was it advantageous? If it was because we could sweat more, why was sweating more more advantageous than having fur? Most other mammals still have their fur. Sweating can't be better _per se._
Regarding UV radiation. That's an interesting theory. But why would the head be more impacted by UV radiation? It seems skin on other parts of the body are equally damaged by sunburn.
Regarding beards, "it's genetic" isn't really an argument. Of course it's genetic that e.g. Indians and East Asians don't grow much beards while Europeans are the opposite. But why the difference? Why beards at all? And why don't woman have beards?
Omg I dont think any other youtube channel has videos of better quality you guys are amazing
I like the way you make the science fanny! Keep on the good work.
You were so busy making hair puns that you forgot to answer the question, genius.
Joe Hansen worked in puns the way other artists might work in oils or clay. It was his true medium. A master.
That thumbnail though😂
Love these science videos!
Comb down with the buns guys.
You made me smile HUGELY from inside thx 😊, I don't have dep
ression btw
Mixing humour with science may entertain, but can also confuse sometimes.
I feel like no one needed this but I love it
Hey thanks Green, I’m always on the road too and love the channel!
Still waiting for Science to fix that hair loss problem.
Stiiiiiillllllll waiting.
.................waiting.
..............................just over here. Waiting.
...............................
.........................Seriously, any time now, guys.
Etaukan
I'll do it. Just give us a min
Ah, great, finally!
Get a hair transplant, mate. It's the only lasting solution. No pun intended.
My big hair question is why is head hair capable of growing with no boundaries but body hair stays the same height?
Excellent video. Didn't expect to understand two important things just a minute in.
I really like your vids and it's amazing what I learn from you and others on UA-cam
Lost most of our long hair so we can sweat and lose heat without having to stop running. I get that, but I never really figured out why we didn't lose all our long hairs. My theory is that the brain is too precious to leave naked and cold, and pubic hair helps protect against a lot of diseases.And I suppose both pubic and armpit hair is less exposed while running so there is less to gain from losing those hairs compared to others. But what about beards, and why only men? Is it something similar to Dothraki ponytails? Also, I still think it's a shame that your tagline isn't simply "Remember, it's okay to be smart."
It could all so be that people simply found hair on the head attractive. It's part of our culture today. I dont see why it wouldn't be part of our ancient ancestors culture.
Maybe evolution in this sense isn’t real?
We switched our Fig leaves for "leather" jackets. I see what you Did there. :)
i just found this channel today and i'm hooked!
That thumbnail is pure art.
let's brush the hair puns aside and cut to the point (of the blade)
i thought i get to learn why we grow eyebrows and eyelashes
They do grow the same way, anyway. When I lost all my hair through chemo, I lost it all. Everywhere. All over. And my underarm hair never came back. 'Tsokay. I hate shaving. But it felt weird between my legs.
I can tell you that without eyelashes and eyebrows, sweat would get into my eyes much more than with them. Eyelashes prevent a lot of airborne particles getting in your eyes. Camels have long eyelashes, and it gives them that kind of protection in their arid environment.
I don't know how the views on your videos are less , you make great content sir.
Thank you I have always wondered this!
You didn’t really answer the question at all??
The whole history of hair thing was interesting, but you didn’t say why humans grow hair the way we do.
Yeah he did lol
neberyx when? Because I never heard him give an actual reason of WHY it only grows where it grows. I only heard him explain WHEN it stopped growing as thick as other apes hair and why it is the color that it is.
@@diegovazquez2714 1:01 also, we evolved sweat.
Vanity. Otherwise it would look like a cootie nest.
Nothing about why some people have wooly hair while others have it straiter
0:40 A Surprise Kyle Hill has appeared
Hello. You are just so entertaining and I learn at the same time. I did not know this. Thanks 👍
Cool video mate :)
Anything: Exists
This Guy: *"Why do you exist huh? What's your aim in life?"*
SCIENCE IS AWESOME!!!
Indeed!
Chaitanya Singh You said it yourself oldtimer
A wonderful coarse indeed, I've bun waiting for this. Not a bald statement at all, it inspires my curliousity. I was braid fur this kind of stuff. You could say I'm locky.
I do hair and I figured I wouldn't know the science behind it but we learned all of this in cosmetology school !! Feeling pretty smart
You mentioned pheromones excreted by humans but I remember an episode of scishow saying there wasnt any evidence that humans had pheromones
There's been studies that showed brain activity based on odors from clothing of the opposite sex. Problem is, no one knows where pheromones are absorbed; no evidence of receptors in the nose.
Since we can't find evidence of something, it's kind of ignored or doesn't exist. After all, if you publish a paper today that states humans react (sexually) to pheromones of the opposite sex based on brain activity MRIs, but can't show the chain of events that led to this reaction, you haven't really done proper science.
Its okay to be smart
In addition to what Crouching Goat, Hidden Donkey said, there have been behavioral psychology studies showing that people have preferences for certain bodily odors on clothing in blind studies, so there's some factor in apocrine body odor that can invoke *feelings* even though we don't know what it is. Call it pheromones, call it sexy BO… whatever. It's a mysterious but probably real thing.
Thanks for the response. I wanted to be snarky about it ;) And yea female BO is a different chemical make up right?
Glad I'm not the one who noticed that.
I have a question if anyone can answer that's fine. Both my parents had blonde hair when they were born, but it started to get darker and turn to brown as they grew up. My brother and I also have that happening to us. Anyone able to explain this?
Kitkatgriffin Loves cookies also curious
Meg Griffin ok no one get angry if this is wrong it's just a guess. I know that hair texture can change during puberty, and that is also inherited. So it may be that different hormones change that when your hormones in general change
In very broad terms, it's about the way DNA works. blond hair means that there is a low concentration of dye being produced, meaning that the genes responsible for producing dye are not activated, but those genes can be activated later in life with a certain kind of protein called a transcription factor (TF). sort of the opposite of what happens with the ability to digest milk using lactase. Mammals lose the ability to digest milk as they grow older, Because they lose the ability to make lactase as their lactase gene is turned off.
What about our eyebrows? I’ve always wondered why so bushy just above the eyes none in the middle (for most people) and why doesn’t it go all the way up to our hairline?
Love your commitment to plaid only shirts
i love the puns
You didnt answer why we have thick hair just on our heads...
Today i woke up, went to the barber shop, came back, go on yt, and this is the first video i see on my home page.
Your thumbnail made me laugh so nice work on that
JUST SAW SCISHOW'S VIDEO ON WHISKERS.... MMM TODAY'S A VERY HAIRY DAY
LagiNaLangAko23 Lol
Chaitanya Singh
Cruel, your profile picture makes people clean the screen
Am I the only one who realized that louse is the singular of lice after watching this?
Thank you for the jokes in this episode. Stressful day just got better
Gave a like for featuring Kyle's hair
I’m using covid as my excuse to grow my hair out already did mustache
What I want to know is this. Before I had cancer, I had hair that was straight as a stick. But after kemotherapy for that cancer, my hair fell out, yes, ALL of it. But when it grew back, it grew curly--and still is. So, WHY! Dr Joe, why? Oh, I like it curly, but I still want to know why the difference...
What a good sense of humour
XD I got a hair loss commercial before this, and the video is about hair!
D puns m8
notification squad
You are killing me with the hair puns
I’ve learnt more whilst watching UA-cam channels like this one than being at school 🤷🏻♀️
Somewhat first
GO MELANIN
I didn't know that hair comes curly or straight because of that. How cool!
Sick video man 👌
I really like argan rain products . the product changed my life. It is stimulating new hair growth, I will continue to use it. The best shampoo is argan rain anymore for me.
First
To be last
Love that Kyle Hill Drop
great video!
But I came to this video because I wanted to know the reason we only have long hair in our heads.
Maybe we used to use our hair as a water filter when drinking water form, let's say, a waterfall or any other source in which the water comes from above. It would prevent some of the bigger particles in the water when we drank water that's passing through it, wouldn't it?
wtf
Don't ever do a video on Gender Fluidity...please.
I'll have to cut you off man.
Nothing personal....stay Texan!
finally caught up with new videos :)
Thor, Loki and Wesley was a great reference😆
I WANTED MORE HAIR PUNS IN THAT INTRO!
"but, dub-ye the actual eff is it" - perfection
2:44 Yeah.... sure.
I observe one thing that I caught my beard coming when I was 15 but the people who are native to other countries, some got late and some get more early than me. Therefore, there must be variation according to the countries to which the person belongs.
The thumbnail omg GORGEOUS HAIR AND MOUSTACHE
Lol the thumbnail is hilarious!!!! I thought he would wear that during the video though...... 😭
Love that intro and that thumbnail.
0:26 the pun-o-meter level just went Over 9000!
What a starting!!!! 😂
The Weasley reference got you an upvote.
When he said "Or a Weasley " I died XD POTTERHEADS 4 LIFE
Awesome thumbnail by the way 😂😂😂
What would happen if i pull out a strand of hair? Would the angle of follicle change too?
4:17 missed opportunity to show the rock instead of vin diesel
I may have this slightly off... In Australia one's pubic bush is called the Tasman(ia). Look at a mad if you're clueless.
Kyle is an impressive human :P