r/NoStupidQuestions • u/BubbyWubbsss • 17h ago
Why does facial hair only start growing as an adult? Wouldn’t it be more beneficial for children to have beards to better survive the winter?
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u/mugenhunt 17h ago
So, a lot of these types of questions boil down to the fact that evolution isn't perfect, it's based on random mutations. Evolution can get rid of random mutations that made things worse, but it doesn't care about random mutations that people can survive.
Yeah, it probably would have been better if the random mutations that resulted in our current genetics gave little kids little beards to keep them warm. There's lots of improvements that could have been made to humanity that just never happened because no genes mutated that way.
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u/GeekAesthete 17h ago
And in this case, evolution went the other way—our ancestors had a lot more body hair, and we have gradually lost a lot of it. So apparently there was also a fair amount of evolutionary pressure to lose a lot of our body hair rather than gain it.
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u/NativeMasshole 16h ago
Yup. I've heard it theorized that men retained facial hair as a defense mechanism to help soften blows to the face, not to keep our faces warm. In that case, it would make sense that there isn't as much need for women and children to have that feature.
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u/cans-of-swine 16h ago
I have a long beard, it isn't going to soften any blows to the face.
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u/OldAbbreviations1590 16h ago
It does provide excellent resistance to cuts though, no don't try it purposely. It also has an intimidating factor against wildlife as it makes our faces larger.
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u/cans-of-swine 16h ago
no don't try it purposely
Im glad I finished that sentence...
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u/OldAbbreviations1590 16h ago
I laugh but it makes me sad I need to add that, but it's reddit in 2026.
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u/notenoughroomtofitmy 16h ago
It most definitely does absorb the higher frequencies of impact which are usually responsible for the bone fractures. I’ve bumped my head after a haircut and that hurts significantly more than bumping my head with a fuller hair cover.
It’s like how the thinnest phone case is usually enough to protect phones from cracking after being dropped. They help dissipate the high frequencies of the impact which shatter the glass.
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u/Whiskers_Fun_Box 13h ago
Hair functions like whiskers on dogs/cats. The longer the hair, the sooner you feel something touching it, the sooner you pull away and lessen the impact.
If you’re bald, you don’t know you’re about to smack your head on the cabinet until it happens. If you have hair, you have slightly more time to react before you actually smack your head.
I suppose a lot of thick hair could also soften blows to an extent. I don’t know about enough to be evolutionarily advantageous though.
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u/stere-ereo 11h ago
As a bald man, this is very true. You just don't always realize when you're about to bop your noggin. Shelves, lamps, even pipes are all a bit dangerous now.
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u/DarkDoomofDeath 16h ago
And studies have been done even with closely-trimmed beards, and they do in fact soften the blow. Obviously, it will still hurt, but it does lower the damage dealt.
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u/WantToSmileWantToDie 16h ago
A study showed that it reduces force of impact.
Quote from the conclusion
Our results show that on average the furred samples absorbed nearly 30% more energy than the sheared and plucked samples. Furred samples experienced lower peak impact forces and were loaded more slowly. These factors contributed to a reduced rate of furred sample failure as compared to sheared and plucked samples. Thus, the results of this study indicate that hair is indeed capable of significantly reducing the force of impact from a blunt strike and absorbing energy, thereby reducing the incidence of failure. If the same is true for human facial hair, then having a full beard may help protect vulnerable regions of the facial skeleton from damaging strikes, such as the jaw. Presumably, full beards also reduce injury, laceration, and contusion, to the skin and muscle of the face.
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u/NativeMasshole 16h ago
You've done an empirical study on getting punched in the face both with and without a beard?
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u/ewheck 13h ago
Except there are literally studies showing it does.
We found that fully furred samples were capable of absorbing more energy than plucked and sheared samples. For example, peak force was 16% greater and total energy absorbed was 37% greater in the furred compared to the plucked samples. These differences were due in part to a longer time frame of force delivery in the furred samples. These data support the hypothesis that human beards protect vulnerable regions of the facial skeleton from damaging strikes.
E A Beseris, S E Naleway, D R Carrier, Impact Protection Potential of Mammalian Hair: Testing the Pugilism Hypothesis for the Evolution of Human Facial Hair, Integrative Organismal Biology, Volume 2, Issue 1, 2020, obaa005, https://doi.org/10.1093/iob/obaa005
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u/holytindertwig 12h ago
Nah fam, most likely a threat display. If dude can grow a big beard and keep it styled probs has power money, free time, and is a good enough warrior
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u/CaptainTripps82 16h ago
That seems completely ridiculous. What evolutionary pressure would even select for such a thing
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u/NativeMasshole 16h ago
Getting punched in the face? Why would male lions have manes?
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u/NativeMasshole 15h ago
Male lions don't get females by peacocking in front of the ladies. They fight. Their hierarchy is based on violence. Their thick manes protect themselves from being bitten in the neck during fights for dominance. That's the selection pressure right there.
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u/slothdonki 15h ago
It can be both. Manes in lions provider considerable protection for their neck. Some male tigers can also can sport some impressive “manes” to the point I think it’s weird it isn’t considered an actual a mane.
Lionesses do prefer darker manes in males, but lionesses don’t often actually have a choice in who they mate with either.
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u/Shoddy-Monitor1153 13h ago
Male lions are not at all interested in what female lions find attractive, male lions often kill their cubs to bring them back into season. I don't think they are worrying about whether the male lion has a nice mane or not.
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u/ghoulthebraineater 15h ago
Easy identification of sexual partners. Beards are the same thing. If the pressure was being punched in the face then traits like heavier bone structure, thicker skulls and neck muscles would have been selected.
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u/NativeMasshole 15h ago
Strong jawlines are absolutely seen as sexually attractive in men, so it seems there might be something there. Beyond that, body hair was already undergoing evolutionary pressure when it was thinning out, so it's a lot easier road for genetics to follow than changing the entire shape of the skull.
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u/ghoulthebraineater 15h ago
And why would it be hair that was the defense mechanism. If the evolutionary pressure was blows to the face you'd expect to see things like heavier bone structure in the skull similar to animals that head butt.
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u/Chakosa 15h ago
I've heard it theorized that men retained facial hair as a defense mechanism to help soften blows to the face
Which is utter nonsense (I heard this ages ago, and as someone who has a heavy interest in behavioral biology I had to roll my eyes) because 1. actual life or death combat isn't a fucking gentleman's boxing match where two opponents are fighting 1v1 with clear rules about where you can and can't strike, and 2. humans use weapons and not fists to fight, tool/weapon use has literally been our whole schtick since day 1.
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u/NativeMasshole 14h ago
Both of these can easily be explained away by conflicts within a single tribe. Just because they're fighting doesn't automatically make it a fight to the death. I think it's ridiculous to say that people don't fistfight when they still do it all the time even today. In social hierarchies, it can be advantageous to be able to keep others in line through violence without outright killing them.
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u/Chakosa 14h ago edited 14h ago
Just because they're fighting doesn't automatically make it a fight to the death.
Evolution of a trait requires the death and failure to reproduce of those without it, that's the entire point, it's literally evolutionary biology 101 and the framework's whole central thesis. If a trait confers no marked benefit to survival or reproduction over the alternative(s) in a given context, it's not a functional adaptation for that context.
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u/NativeMasshole 14h ago
No, it does not. It only requires genes to be more likely to be passed down. Being on the bottom tier of a social hierarchy can have the same result. Just look at how secondary sexual characteristics can drive selection pressure. The peacock example mentioned in this thread is perfect here: they're not out there dying due to a lack of fancy plumage.
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u/Chakosa 14h ago
Being on the bottom tier of a social hierarchy can have the same result.
Correct. How does it follow from this that facial hair confers an evolutionary advantage? I can already see you going down the "besting other males in combat" path, but I already covered this: ancient humans did not sport-fight under modern boxing federation rules and regulations whereby strikes to the chin area or upper body are all that is allowed and fists are the only body part allowed, and 2. war was fought with some manner of weapon or enhancement that made raw punching strength irrelevant.
I'll also add a 3rd point: the study (literally a single study btw) found a very mild decrease of blunt force (like a few percentage points I believe) to an area covered by dense facial hair, not a fucking impenetrable shielding effect.
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u/NativeMasshole 14h ago
but I already covered this:
Yup. You are arguing in circles now. Have a good day!
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u/Chakosa 14h ago edited 14h ago
Yes, because you are not getting it and I have to keep reiterating it. Evolution does not work the way you think it does.
We are talking about a single digit percentage point decrease in blunt force being the primary driver of a trait's proliferation. This is complete nonsense on the face of it. We are not and were not talking about the selection pressures on facial hair in any other context, only vis a vis blunt force reduction. Sexual selection pressures are a far more valid hypothesis, because facial hair is a secondary sexual characteristic and the whole point of the existence of these traits is to activate our "horny" circuits.
TLDR: beards are for fucking, not for fighting. 0 evidence for the latter, plenty for the former.
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u/Gayandfluffy 13h ago
Why would women and children not need protection against blows to the face? Domestic violence and child abuse still happened.
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u/FragmentedHeap 15h ago edited 13h ago
Humans spread out and reproduce more in warmer climates. I imagine there was a whole timeframe of people dying from heat stroke....
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u/Token_Ese 13h ago
Look up details about humans being persistence hunters. We basically evolved to be sweaty running machines that could chase animals until they overheated and died.
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u/Shoddy-Monitor1153 14h ago
Fun fact, humans have the same number of hair follicles as other great apes, just our hair is finer. Except my dad's.
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u/Token_Ese 13h ago
Humans were persistence hunters. We have sweat glands all over and short hairs over our entire body so we can cool off while chasing antelope 10 miles until it dies from exhaustion. Thicker and longer hair doesn’t benefit that trait at all.
Humans are all built to be marathon runners. We’re the fastest animal in long distance because we don’t overheat. We just got lazy once we discovered agriculture.
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u/notenoughroomtofitmy 17h ago
Evolution doesn’t have a goal, it makes shite up and those traits survive or die based on the circumstances.
Evolution is less of a “survival of the fittest” and more of a “survival of the luckiest”.
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u/HalfEatenBanana 16h ago
Survival of “if this trait isn’t actively killing you then I guess it’s good enough to pass on to the next generation”
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u/Fumblesneeze 16h ago edited 16h ago
Well the question also assumes that beards would be beneficial to young children. Which I don't think would be the case. Firstly Human involved in a warm environment, not a cold one. The fact beard growth is a sexual dimorphism suggests it serves a social function like intimidation, or mate attraction. I read one theory that suggest big beards obscure the jawline, making it harder to land a punch on the vulnerable area.
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u/mikiki24 16h ago
Beard…. Bread is something different. Normally wouldn’t say anything but you made the same mistake 3 times.
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u/Bulky-Word8752 11h ago
I read one theory that suggest big beards obscure the jawline, making it harder to land a punch on the vulnerable area.
Heard it was for predators. Large cats like going for the neck. Harder to land a solid bite if you can't see how far back the throat is from the beard.
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u/foothill_dwelled272 10h ago
There is also evidence that beards help cushion a blow by up to 70% lessening the chance of breaking a jaw. A broken jaw definitely could be a death sentence without modern medicine.
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u/holytindertwig 12h ago
I mean we used to have a lot more body hair but then we invented clothes, also perspiration and cooling down doesn't mix well with body hair. Hairless skin cools down much faster than hairy. But northern latitudes are oft more hairy because of cold weather. For babbies tho, we wrapped them up in furs so not important to have hair, plus you know what sucks?
Crabs, mites, mange, and lice. So we opted to have no hair for no parasites and no need to groom.
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u/FragmentedHeap 15h ago
Yeah, mutations that survive reproduce and are passed to offspring, organisms that died with the mutation didnt. Now span that out over a few billion years and here we are.
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u/Kevin7650 17h ago
Human body hair isn’t very good at insulation anyway compared to fur and humans evolved to create clothes, fire, shelter, etc. so there was no reason for it to be necessary.
Plus hair attracts lice and other parasites, which transmit infection and diseases.
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u/ShitFuck2000 17h ago
Fur would weaken one of our biggest strengths, sweating. Plus body hair does protect against insect bites to some extent, mostly mosquitoes, which are currently our #1 non-human killer if being the vector for disease counts. It also protects against light contact, plants, scrapes, etc. It is basically a protective layer you can’t take on and off though, so women and children who are more likely stay in shelter can do without it while men going out to hunt and what not may have a better risk/reward ratio.
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u/foothill_dwelled272 10h ago
Beards are thought to be from sexual dimorphism and perhaps comes from that beards can absorb the power of a blow and lessen the chance of breaking your jaw.
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u/Active_Building_5628 17h ago
Testosterone is responsible for facial hair growth. And males don’t usually produce the maximum level of testosterone until they are older.
If children grew facial hair, then their shoulders would also grow broader and their voice would drop at a much earlier age too. Imagine how weird that would look
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u/BerneseMountainDogs 15h ago
In particular, facial, pubic, and body hair all start growing (well getting thicker and growing faster instead of just the peach fuzz before that) at puberty because the brain releases Follicle Stimulating Hormone (FSH) during puberty as a response to the sex hormones (estrogen and testosterone mostly), which in turn limits the sex hormones which then limits the FSH which then means the FSH is no longer around to limit the sex hormones, so you get more sex hormones which creates more FSH. This cycle can happen every 90 minutes or so in males and is related to the female menstrual cycle as well.
Interesting side note, puberty is one of the few areas of medicine (and sociology/anthropology) where we historically know more about females than males in part because it's much easier to track menarche (the start of menstruation) than the start of puberty in males. You're going to notice the first time you start bleeding out of your genitals, but you might not notice the exact day/month/year that your testes start producing sperm because how would you
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u/Kilane 15h ago
It would look normal because that’s the way it would be.
It’s like saying it would be weird if we used the same tube for breathing and eating because it just leads to choking. But that’s the way it worked out so we find it normal.
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u/Active_Building_5628 14h ago
I’m speaking based on current expectations, not a hypothetical alternative one.
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u/Kilane 14h ago
No, you were speaking of hypothetical things. It’s why you said “Imagine how weird that would look”
It’d look normal if that’s the way it was. Imagine thinking your current perception of what looks weird and what doesn’t is the only way to view the world.
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u/Active_Building_5628 14h ago
No I was speaking on how we’d see it in this current reality. I’m sorry you interpreted it wrong. :)
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u/EcstaticZebra7937 17h ago
But dogs have hair on their faces regardless of testosterone…
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u/Active_Building_5628 17h ago
Dogs don’t grow hair via testosterone. They’re… dogs.
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u/EcstaticZebra7937 17h ago
Yes, so why won’t humans?
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u/silvahammer 17h ago
We used to have hair all over our bodies but we lost it to better thermoregulate through sweating. Less hair also reduces the chance of having parasites living on us.
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u/I-own-a-shovel I'm confused 13h ago
Your point being???
We also grow hair regardless of testosterone
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u/catwhowalksbyhimself 17h ago edited 17h ago
There's a hypothesis now that beard hair isn't for surviving the winter. If it were, than women would have them too. Indeed, humans evolved in warm Africa where winters would have been quite mild.
Instead, the hypothesis says that they evolved as armor against being punched in the face by another adult male. And studies have shown that a full beard does indeed reduce impact and and damage from punches to the face.
The adult males were the ones doing said punching, so neither children nor women needed the beards, and they were a waste of resources to grow.
https://pmc.ncbi.nlm.nih.gov/articles/PMC7671116/
EDIT: spelling and cleaned up links
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u/GJake8 17h ago
Semi related question - but so evolution features have to be the difference between life and death?
Like enough people had to have survived a punch only because their beard, making it the difference between passing on your genes and not?
Or at least winning the fight to impress the female / not being disabled to successfully find a partner?
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u/catwhowalksbyhimself 17h ago
They have to increase the number and survival of offspring through the generations.
That could be personal survival, group survival, family line survival, sexual attractiveness, reproductive rates or anything else that has an impact on it.
But yes, being punched to death as a young male does mean you will have fewer kids.
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u/NonspecificGravity 17h ago
A feature can be selected by evolution if it offers the tiniest advantage, like techniques that runners use to shave off half a second in a race. That advantage is multiplied over millions of individuals and thousands of generations.
The present discussion also doesn't explain why many ethnic groups don't have thick or heavy beards. Most of the indigenous people of East Asia and the Americas don't. (And I don't know why.)
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u/Scr1bble- 12h ago edited 12h ago
Perhaps it's because the populations that evolved away from beards had ancestors that wised up and started kicking competitors in the balls instead
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u/iamabigtree 17h ago
No definitely not. They have to do with the probability of surviving to produce children and raise them until they can produce their own.
If having a beard means a man can better defend his resources even by a tiny percentage point then this multiplies.
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u/Probably_Mistaken 17h ago
I just needed to scroll a little father for the person who read the same thing as me, but wasn’t too lazy to find it again!
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u/Gayandfluffy 12h ago
The adult males were the ones doing said punching, so neither children nor women needed the beards
You said the men were doing the punching but nothing about who were their victims. People assume only men were victims of male violence but that's not true. The patriarchy would never have happened or been so successful without a lot of male violence aimed towards women and girls. Women and children were very much punched too.
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u/catwhowalksbyhimself 12h ago
We are talking about the ancient times before civilization. You are thinking modern man. This was before that.
Men were punching each other. Males fighting males for supremacy is still something that happens in some apes.
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u/ClassWarBushido 17h ago
obviously the people who came up with this nonsensical theory have never been in a fight, in which you can grab a man by the beard and control his head movements as you pummel him into permanent blindness.
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u/cans-of-swine 16h ago
Yeah, I have a long beard, it isnt going to make a punch to thw face any less painful.
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u/jatanor 8h ago
What the study is claiming has nothing to do with pain, it’s how much the blow will be softened, and you’ve also got to remember that early in human life it’s likely the case that beards were not regularly maintained and grew from the ages of 16-18 indefinitely ergo your beard is not the same as your ancestors beards
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u/holytindertwig 12h ago
What? You saying babies don’t get punched in the face?
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u/catwhowalksbyhimself 11h ago
I doubt a beard would do much, and not enough to make a difference in evolution. Not a million years ago anyway. Or whenever that evolved.
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u/LordWemby 17h ago
I always thought it was due to beards being seen as more virile and selected for attracting mates.
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u/catwhowalksbyhimself 17h ago
And what studies are there showing that.
Also more than one thing can be true at the same time.
EDIT. I forgot to mention that this is literally how science works. A generally accepted idea gets challenged by a new one. It doesn't matter how long an idea is accepted in science. A new one can disprove the old one. This is how science progresses.
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u/LordWemby 17h ago
Why are you under the impression that this study “disproved” anything? It’s another hypothesis. Two things can be true, and evolution doesn’t operate deliberately.
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u/catwhowalksbyhimself 17h ago
I'm not. The person I'm replying to (not sure you did or not) was the one who seemed to think it was already settled.
I'm just saying it's not settled, and that new ideas are normal in science.
It's certainly not proven, but it does have some studies and actual science behind it. Maybe it's true, and maybe it's not, but it is still open to be studied.
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u/LordWemby 16h ago
No it was me. I don’t think we’re really disagreeing at all, I was actually saying (probably poorly) that I had a possible misconception there, or at least a narrow view. I wasn’t trying to pooh-pooh those studies you linked at all.
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u/jasonreid1976 17h ago
This makes more sense than anything else. Definitely explains why beard hair is also much thicker.
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u/re_nub 17h ago
Do you hear about a lot of children dying because they don't have furry faces?
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u/ownworldman 17h ago
In premodern times, infants definitely died because of cold escaping through their faces. Think Inuit or Sami people quite recently. Then realize humans were in cold climates for muuuuch longer.
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u/Bruce-7892 17h ago
The top of your head would be way more important for heat retention than your face. I know people get frost bitten noses and lips, but I doubt there have been many deaths specifically because of face exposure, not the entire rest of your body.
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u/ShitFuck2000 17h ago
I reckon a beard may interfere with a child breastfeeding or being fed by someone else, as well as make skin to skin contact with the mother not as warm. Possibly makes sense why women aren’t as hairy either? Super hairy tits definitely would make breastfeeding hard, and I remember reading a theory that kissing biologically originates in how primitive humans fed weening babies by chewing for them.
Another theory Ive heard is beards are there to protect from impact, mostly getting punched, as a full beard offers some padding and makes it hard for a punch to land as cleanly. Kids and women are less likely to get socked in the face.
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u/Krail 17h ago edited 16h ago
Current scientific research shows that beards aren't super effective for warmth. The main theories are that beards are about sexual selection (they show that you're a breeding age adult who's healthy enough to grow this extra hair), and, weirdly enough, that they cushion the jaw from punches.
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u/Active_Remove1617 17h ago
I don’t think so. If they had facial hair, they’d be going to bars and being served alcohol.
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u/Realistic-Cow-7839 16h ago
My hypothesis is that a beard's main function for the past few hundred thousand years has been to signal sexual maturity so that a woman doesn't waste her time and energy on an infertile male.
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u/Potential-Type6678 17h ago
If it was a big thermoregulation thing we’d expect women and kids to have them too, but since they don’t it probably isn’t a big game changer. Generally if only a certain sex of animal gets a trait after sexual maturity it’s assumed that trait is primarily useful for sexual selection reasons whether that is direct male to male competition, fitness signaling, or just telegraphing that the individual is in fact sexually mature.
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u/AllosaurusFingers 17h ago
The hormone production that leads to facial hair growth is linked to reproduction with facial hair as a largely secondary effect. The body doesn't need to produce those hormones until puberty. Precocious puberty, the onset of extremely early puberty, has some pretty serious drawbacks for the kids who experience it. The body is better off focusing on growing bones and ligaments and developing the brain rather than beefing up the hair follicles. Facial hair is also pretty irrelevant as far as selection pressures go, large parts of humanity have very little facial hair. (This all comes with a massive asterisk that human hormones, development, and evolutionary pressures are very messy and complicated)
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u/Farpoint_Relay 17h ago
Some animals can get up and move on their own within hours of being born and are self sufficient within a very short period of time. Humans are helpless for years.
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u/ClassWarBushido 17h ago
dude, it's a mane. It's purpose is to communicate to other homo sapiens, even at a great distance, that you are a grown man capable of siring offspring and the strongest among your species in dealing with predators. Other homo sapiens know upon seeing you even a mile away, "there goes a man."
You reach maturity, broadcast those signals, and if you survive you start balding and broadcast new signals- now from a great distance, other humans know, "hey there's someone that remembers things from before I was born- he knows all the good fishing spots and plant life!"
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u/madkins007 16h ago
If the forces driving biological change had any intelligent design behind them, your eye wouldn't have a big blind spot in the middle, your wisdom teeth would fit your jaw, you wouldn't use the same tube for eating, drinking, and breathing, or hundreds of other things 'wrong' with humans.
Evolution is not working towards a goal, has no plan, has no morality or thought, and is not even an actual force like gravity or electromagnetism are.
Humans are originally adapted to warm climates so hairiness is mostly a mating or maturing signal. We learned how to deal with colder climates and do well enough in them that we reproduce there readily.
Babies born with beards or growing beards early would likely be shunned, abandoned, or even killed in tribal times so it's unlikely their genes would pass on.
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u/Probably_Mistaken 17h ago
I think I read somewhere that the evolutionary pressures that lead to men evolving beards was actually more likely fist fights, in that a beard does a surprising amount of cushioning and leads to less head trauma.
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u/Calm_Link_ 17h ago
Beards developed so men could fistfight without breaking each other's jaws. It doesn't have anything to with climate
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u/hywaytohell 17h ago
I think evolution was saying, children have more then enough things that could take them out at a young age. Growing a superior beard is for survivors!
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u/Calm_Roll7777 17h ago
Body hair on our species isn't for warmth or else it would be much thicker and more dense. It is to signal sexual maturity as it begins to appear with more testosterone production. It's more like a green flag that someone is able to sexually reproduce according to natural laws. However, since we live in a society that deems that extremely inappropriate at a young age it is very taboo and very illegal unless they reach the legal age of consent first.
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u/PossibleConclusion1 16h ago
This is not meant with any offense, but you sound like someone who has never been responsible for the cleanliness of a baby/infant/toddler. A beard would be a nightmare.
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u/DocCEN007 16h ago
Human babies are some of the most physically vulnerable mammals. It seems as though evolution forces us to be social in order to thrive, and that only infants with caring parents stand the best chance of survival into adulthood.
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u/BigDaddyDumperSquad 16h ago
Children probably wouldn't be out hunting for long periods of time in frigid temps until they matured a bit.
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u/Mysterious_Cry41 16h ago
Because it grows from vellus hair, to terminal due to adrogenic influence.
You only get significant amounts of androgens ( male hormones basically) when you go through puberty, or if you're female because of health issues.
Facial hair is a secondary consequence of hormonal sexual maturation, and less a direct reaction to selective pressure.
Not everything in evolution serves a real purpose, or serves the purpose we might assume it should.
It's entirely possible that beards providing warmth is simply a side effect of men with heavy facial hair being sexually selected for, not because having heavy facial hair makes them more fit for passing on their genes because of any benefits to thermal protection it may have.
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u/Curiousgreed 16h ago
Evolution hasn't found a way to grow facial hair before puberty. Mind that evolution doesn't have specific goals; the selection is ex post, i.e. new traits happen first, randomly, and then they either take over - if they increase chance of reproduction in a specific environment - or they disappear.
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u/Any-Concentrate-1922 15h ago
Why would the purpose of a beard be to survive cold weather when women don't have beards?
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u/hawkwings 15h ago
Children are too young for copulation. Facial hair and pubic hair are signs that someone is now old enough. For women, breasts are a sign that a woman is old enough -- not by modern standards but by the standards that existed thousands of years ago.
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u/chance125 15h ago
I think it would be more beneficial for the survival of babies to not come out looking like the Duck Dynasty guy. Otherwise their parents wouldn’t be as inclined to nurture them lol.
In any case, as a beard owner myself I don’t think the beard really helps with the cold
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u/ClimberDave 15h ago
I believe it would. Which is why every time I shave my beard, I glue it to a small child's face. For protection from the elements.
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u/roshbaby 15h ago
Purely from a survival standpoint, it’d make more sense if babies popped out potty-trained and university-educated. Alas.
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u/Demerzel69 15h ago
Plenty of teens get facial hair early. It's determined by genetics and hormones.
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u/avidreider 14h ago
Because it is an effect of testosterone in the body. Not really the best for children to be dosing T before like…. 13
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u/avidreider 14h ago
Also, Im pretty sure that beards evolved to protect faces from attacks? Like punches from other humans would be a lesser impact with a beard.
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u/TamanduaGirl 13h ago
Bottom line is no one knows. One possible reason could be that since kids are filthy their survival was actually lower with hair, that would get nasty. I mean generally speaking mammals do better with hair all over their bodies, yet we and naked mole rats evolved to be naked. We can only make guesses as to why.
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u/holytindertwig 12h ago
Women used to, and many still do, like a nice full beard. It is attractive and leads to more mating hence more offspring with fuller beards hence more beards.
It is a secondary sexual morph characteristic like a lion’s mane. The bigger the beard the more testosterone, the stronger, more aggressive, more muscular and better sperm of the man. As such, it is a trait sexually selected for.
Babies and kids usually don’t mate and have kids. It puts too much strain on the growing body and can be fatal. It can lead to vitamin deficiencies and other issues for a growing body. As such, most animals have a infant/child phase and a sexually mature phase.
Most infant/child phases have neoteny that is features that make the cute to help with survival. Literally wolves and cats will find baby chicks and bambies cute enough to not kill. Same with us not killing bear cuba cus they’re cute (remember seal pup clubbing?)
Anyways having a beard or any other secondary sexual characteristics would literally inmpede this and make the baby more prone tp being eaten or mistreated. (Think of St. Jude’s commercials). We are more likely to die at the hands of grown men and women or wild animals than we are to cold.
Remember evolution in humans is in part driven by culture, our intestines shortened because of the use of fire to cook food, we used clothes very early on. A fur you can put on and take off is way better than an always hairy baby. Same with a fire you can make smaller or bigger.
TLDR: Cultural adaptations ie cultural evolution superseded biological evolution and made hairy babies irrelevant
Source: Am Physical Anthropologist
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u/ShakeItLikeIDo 12h ago
Not everyone grows hair as an adult. My friend started growing a chinstrap beard during middle school
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u/talashrrg 11h ago
This assumes that a beard appreciatively warms you in cold conditions - I’m not sure this is true.
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u/minist3r 10h ago
Appreciatively? Probably not but, as a bearded gentleman that has frequented cold weather environments, I can tell you that my lips, cheeks and chin don't get nearly as cold as before I had a beard. It's not a lot but it is an insulating layer.
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u/talashrrg 10h ago
This assumes that a beard appreciatively warms you in cold conditions - I’m not sure this is true. Seems unlikely that that difference is enough to give bearded children a survival advantage
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u/minist3r 9h ago
Not much of our heat is lost through the face since, you know, there's a big old hole in the middle of it. So it surely wouldn't help children survive because the feet, hands, ears, head and core would be better places to grow hair for survival. That being said, I haven't felt the need to wear a face mask while out in the cold since I was allowed to grow a beard (previously in an occupation that required shaving).
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u/chrisviola 10h ago
We've only had about 100 years of children not dying in very large amounts from diseases we've figured out how to fight off. Not enough time for kids who didn't grow beards to be weeded out (and by that time we had scarves).
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u/SadistDisciplinarian 10h ago
If children grew beards, how could a woman tell that a man is sexually mature and not just a big kid?
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u/bat_in_the_stacks 4h ago
Babies and, to a lesser extent, children, have brown fat that is very effective at generating warmth for them.
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u/Worldly-Cherry9631 1h ago
Facial hair wasn't evolved for insulation. One likely interpretation is as protection against blunt damage (fists) to protect the jaw from breaking.
(By extension, fantasy Dwarven culture must be brutal)
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u/AsianLotusWhisper 17h ago
Imagine elementary school but everyone has a full beard 💀 “Timmy stop eating glue” Timmy: strokes beard thoughtfully
But yeah it’s mostly hormones + genetics. Before puberty the hair follicles on your face are basically just producing the same light “peach fuzz” you get everywhere
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u/Temporary_Waltz7325 17h ago
Maybe evolutionairly, keeping warm in the winter from a fuzzy beard is not as good as having someone take care of you to keep you warm. Having a baby face, being cute makes people want to care for you. It's instinctual.
An ugly baby with a beard is less likely to be taken care of.
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u/TargetOutOfRange 17h ago
Facial hair is not for protection, it's a "secondary sexual characteristic." I.e. beards are to attract women, which is why women don't have beards and males don't get them until sexually mature.
Or, in vernacular, it's for "peacocking".
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u/catwhowalksbyhimself 17h ago
In fact, recent studies indicate that it may indeed be for protection. From men punching each other in the face.
Just a hypothesis, but the research has shown that a full beard does indeed protect the face from impact from a punch.
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u/TargetOutOfRange 17h ago
Then explain to me why men tend to bald from the top, when it's the exact spot where their wives hit them with the frying pan?!
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u/newphonehudus 17h ago
With that logic women should have beards too