[HN Gopher] Investigating the case of human nose shape and clima...
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Investigating the case of human nose shape and climate adaptation
(2017)
Author : thunderbong
Score : 125 points
Date : 2025-01-30 08:04 UTC (14 hours ago)
(HTM) web link (journals.plos.org)
(TXT) w3m dump (journals.plos.org)
| baxtr wrote:
| From the author summary:
|
| _> We find that variation in both nares width and alar base
| width appear to have experienced accelerated divergence across
| human populations. We also find that the geospatial distribution
| of nares width is correlated with temperature, and absolute
| humidity, but not with relative humidity. Our results support the
| claim that local adaptation to climate may have had a role in the
| evolution of nose shape differences across human populations._
|
| I really wonder how nose shape can affect evolution. What is the
| mechanism? How can better air lead to higher numbers of
| successful offspring or fatalities?
| kseistrup wrote:
| The parameters affect the temperature and humidity of the air
| that reaches the lungs. E.g., a long slender nose could perhaps
| moisten and warm up dry frosty air better than a shorter wider
| nose.
| 0xEF wrote:
| Speaking as someone with a long slender nose, I have my
| doubts about it moistening dry frosty air. During the
| Winters, the only thing my nose seems to be good for is
| producing blood and dried mucus wafers like some cursed
| Triscuit factory.
| croisillon wrote:
| Yay free proteins!
| kseistrup wrote:
| It's not about your nose. It's about the relative
| differences of the air reaching the lungs when inhaled
| through different nose. You may not think that your nose
| does a very good job (or perhaps I picked a wrong example),
| but perhaps the job would get done much worse by a short
| wider nose.
|
| Some environmental parameters are temperature and absolute
| humidity. But there are also significant differences in sex
| when a other parameters are equal. So perhaps the
| correlation is not so straight forward.
| ChrisMarshallNY wrote:
| Andean Indians are known for fairly wide, prominent
| noses. They also have massive thoraxes and lung capacity.
| 0xEF wrote:
| I can see that. Contrary to my personal feelings about my
| own nose, having grown up in a more Northern latitude
| where Winters were much, much harsher than what I
| experience now, there was a few key things I learned at
| an early age that stuck with me well into adulthood.
|
| Breathing through your nose in the cold while walking to
| class was one of them. I heard this a lot back then, the
| logic being as you propose; that it just gives the cold
| air a bit more time to warm before it reaches your core.
| Adding to that, you were also supposed to breathe slowly,
| rather than taking fast, gulping breathes. That just
| added to the reasons to avoid over-exerting yourself in
| the cold, which poses other risks.
|
| Other stuff had more to do with choice of clothing
| material, layering, etc, but that's not really applicable
| to this conversation.
|
| Interestingly, while it still does get cold where I live
| now, nobody really pays attention to these rules. I'd say
| the difference between the two areas is something like
| -5F on average, give or take. I am not sure how
| significant that is.
| lproven wrote:
| > Breathing through your nose in the cold while walking
| to class was one of them.
|
| After extensive nasal surgery in 2009 this became an
| option for me again, after over 20 years when it wasn't.
|
| I discovered a less-discussed rider: yes, it seems
| gentler on the lungs to breathe in through your nose in
| sub-zero weather, _but_ there is a condition: you should
| breathe _out_ through your nose as well.
|
| Exhaling warms the structures in the nose so it can warm
| the next inhalation.
|
| But, for me, that same sub-zero weather often causes my
| nose to make more mucus -- so breathing both in _and_ out
| means a lot more use of a handkerchief, or a nasty snotty
| moustache.
|
| It's sometimes simply not worth it. :-/
| homebrewer wrote:
| Honestly, all this makes zero difference if you're not
| frail or in advanced age. I regularly experience winter
| temperatures of -30degC or lower (-40deg is not
| infrequent), and it really doesn't matter how you
| breathe.
| kjellsbells wrote:
| Might make a big difference if you are exerting yourself,
| eg cycling.
|
| Discussion here from 2019 about heat exchanger masks
| seems relevant. They warm incoming air using the heat
| from outgoing breaths.
|
| https://news.ycombinator.com/item?id=39128311
| cyrillite wrote:
| Respiratory efficiency is a pillar of health and performance,
| from sleep to hunting and fighting. I wouldn't be surprised to
| find that marginal gains make a big difference and can be
| passed on.
| lm28469 wrote:
| > How can better air lead to higher numbers of successful
| offspring or fatalities?
|
| Try running XX hours after an antelope and report back, most
| animals aren't optimised for long distance, humans are, you can
| hunt most things by following them and waiting for them to
| collapse, surely having better air intake helps. It might be
| something as dumb as more antelope meat = more social points =
| you get to bang more.
|
| Why do 70%+ of the world population has brown eyes ? It offer
| marginal UV resistance but nobody becomes blind or sterile
| because they have blue eyes, certainly not before they can
| reproduce. Chances of reproduction can also be dictated by
| other things like attractiveness, and these are also very
| dependant on cultures and time periods.
| DiscourseFan wrote:
| Its more like if your tribe has access to more meat they can
| produce more offspring. I wouldn't think of this in terms of
| individual prowess.
| BurningFrog wrote:
| Pretty sure the best hunter gets the most kids on average.
| DiscourseFan wrote:
| Source?
| olddustytrail wrote:
| Pretty sure the guy who's off hunting for days at a time
| _thinks_ he has the most kids...
| capitainenemo wrote:
| Well, at least one selection pressure for blue exists -
| modestly better vision in low light levels.
| euroderf wrote:
| > Try running XX hours after an antelope and report back,
| most animals aren't optimised for long distance, humans are,
| you can hunt most things by following them and waiting for
| them to collapse
|
| According to this theory, the rhythm was to walk a long long
| time and maybe hungry too, then a burst of activity, then
| stuff your face, then pass out for a while, then repeat. It
| seems logical & sensible & probable.
| DrScientist wrote:
| Nose filters, and adjusts air temperature and humidity - it's
| not just a passive in/out hole.
|
| Evaporation is a big factor in both controlling temperature and
| water retention/loss ( that's why dogs pant in hot weather ).
|
| Remember the surface of your lungs are topologically on the
| outside - they are large and wet and are sensitive to both
| physical dust etc as well as potential infection.
|
| The nose design has to find the best balance across all these
| factors ( as well as being important in the sense of smell ).
| wiether wrote:
| Silly suggestions related to snoring:
|
| - harder to find mating partner before earplugs were inventend
|
| - easier for your enemies/predators to catch you in your sleep
| SamBam wrote:
| The article mentions an increase in upper respiratory tract
| infections in the air being breathed in is not humid enough.
| The hypothesis seems to be that in drier climates, humans need
| longer noses to increase the humidity of the air to an optimal
| level.
| justlikereddit wrote:
| >This work was supported in part by the United States National
| Institute of Justice, the United States Department of Defense
| nothrowaways wrote:
| This is how our understanding about the world moves forward.
| metalman wrote:
| There are a large amount of enviromental adaptations in many
| human populations, a lot of them to do with enzimatic
| adaptations. Climate as a term in this context is only usefull if
| you include, everything, diet, the ability to pass certain
| contaminents, such as high arsinic concentrations in water, vs
| binding say calcium. The full list, is, well, everything!,
| horribly complex, the nose ,perhaps working as a proxy indicator
| for a number of less visible adaptations, as succes in more
| extream environments is absolutly dependent on multiple
| adaptations, none of which is optional over generational time
| spans, as extream conditions, in an already extream environment,
| are going to eliminate marginal indivduals.
| microtherion wrote:
| Weirdly, I saw this paper mentioned just this morning, in the
| context of an r/AskHistorians post discounting the possibility of
| an African origin for Olmecs. Sounded interesting, and then I saw
| it linked here.
| dagenleg wrote:
| Same. Feels like we exist in a very small bubble doesn't it?
| abricq wrote:
| On a slightly related topic, I remember to have seen an
| exposition where an artist was asked to represents what a human
| who has naturally evolved to survive a car crash might look like.
| And it has a cool / terrifying website:
| http://www.meetgraham.com.au/view-graham
|
| Quite fascinating topic to wonder about: how long will it take
| for the modern era to genetically change us ?
| highcountess wrote:
| To answer your question, it already has changed us in many
| ways. You are not the only one who does not realize this
| though. It is in fact the prevailing position.
|
| We have diseases and genetic defects, among other impacts
| through modern behaviors and environments/toxins, which are
| also retained in the genetic mutational load. We even have a
| whole lot of energy and human activity working to counter
| evolutionary pressures and assure those accumulated mutational
| loads remain in the genetic code.
| amanaplanacanal wrote:
| Fitness depends on the specific environment the creature is
| in. Environmental fitness for the ancestral environment when
| all humans were hunter-gatherers is not necessarily the same
| as fitness for living in an industrial society. Evolutionary
| pressure still works just fine.
| spacebanana7 wrote:
| Humans are beyond evolution. There's no meaningful selection
| pressure in our environment that kills people before
| reproductive age, so there's no reward for adaptations.
| mattigames wrote:
| I have always considered that a bug, not a feature.
| svara wrote:
| Totally wrong, killing humans is not required for evolution.
|
| Ignoring genetic drift and taking into account only natural
| selection, all that's needed is differences in fitness, i.e.
| differences in how much an individual contributes to the gene
| pool of future generations.
| hammock wrote:
| This. "Natural selection" refers to selection and
| survivability of _traits,_ not of individuals. Evolution is
| how that selection process then manifests itself over time
| in a population.
| Galaxeblaffer wrote:
| can't remember where i read this, but significant and big
| leaps in evolution seem to often happen in times of
| crisis when the environment forces it. that's not to say
| that evolution doesn't happen all the time with little
| pressure it's just very slow when things are more stable.
| by extension big leaps in evolution can really be down to
| a low number of individuals. read an article about a
| genetic study claiming the human population was down to a
| few thousand individuals around 90k years ago.
| quesera wrote:
| Punctuated equilibrium.
|
| Not sure if he's the originator, but I'm pretty sure I
| learned about it in a Richard Dawkins book.
| pfannkuchen wrote:
| Crisis presumably doesn't affect the rate of mutation, so
| is the mechanism here just that there is a tight filter
| that from the perspective of future animals made the
| species more like themselves, because by definition the
| future animals have passed the filter?
|
| Like the traits must have already been present in some
| lower frequency pre crisis, and the crisis distills the
| traits which are selected for by the crisis.
|
| So probably less evolution moves faster during crisis and
| more that there is an interesting survivorship bias
| related to crisis when analyzing the change of a species
| over time.
| thaumasiotes wrote:
| Well...
|
| Evolution is not primarily driven by the mutation rate.
| It's primarily driven by differential success of already-
| existing genetic variation. Over the very, very long
| term, you need mutation to be the source of that genetic
| variation, but over the short term mutation is mostly
| just harmful, and this:
|
| > Like the traits must have already been present in some
| lower frequency pre crisis, and the crisis distills the
| traits which are selected for by the crisis.
|
| is correct.
|
| > So probably less evolution moves faster during crisis
| and more that there is an interesting survivorship bias
| related to crisis when analyzing the change of a species
| over time.
|
| This is conceptually wrong; in this context "survivorship
| bias" bears a technical name you've probably heard of,
| "natural selection". A stronger survivorship bias means
| faster evolution.
| hammock wrote:
| That all seems logical. What is the connection to the
| previous point?
| mattigames wrote:
| People is taking the parent comment literally but that was
| very clearly not the intent, obviously human evolution in
| the stricly technical biological sense its still happening
| (e.g. genetic diversity) but is by far currently molded by
| changes done by humanity itself (e.g. industralization,
| tech) not by factors outside their control as it happens
| with every other animal on earth, and as it adapts to the
| environment of its own creation it also loses the traits
| that favor surviving outside of such an environemnt (e.g.
| in case of disaster and we lose some of that environment,
| like a nuclear holocaust)
|
| There are ways we could avoid losing most of that
| survivability but of course they are wildly unpopular such
| as actively discourage people with terrible inheritable
| diseases to procreate (e.g. ALS, Lupus), favor reproduction
| of people with both higher intelligence and physical skills
| (e.g. goverment subsidies for their parents, tied to their
| children grades and general well being)
| washadjeffmad wrote:
| Interesting. So how do you explain menopause and other
| population or age scale adaptations?
|
| Humans aren't individuals, no matter how certain blips of
| modern culturalism pretend.
| snarf21 wrote:
| Really? I was under the understanding that we have continued
| to get taller and bigger driven by out our access to
| nutrition and medicine over the last couple of centuries.
| InfiniteLoup wrote:
| Is this really a genetic adaptation to the environment or
| rather fulfilling the inherent growth potential that would
| otherwise be inhibited by nutrient deficiency?
| _DeadFred_ wrote:
| By all the 'no one under 6'2"' tinder jokes I'd say it's
| being incorporated into genetics.
| swalling wrote:
| Dead wrong.
| https://en.wikipedia.org/wiki/Recent_human_evolution
| ninetyninenine wrote:
| There is incredibly high sexual selection. Birth control is
| effecting this.
|
| Note that sexual selection selects for health, wealth and
| reputation. Women are doing most of the selection here.
| SamBam wrote:
| Evidence?
|
| Take just the easiest to measure of those factors, wealth.
| Per your hypothesis, wealthier men should have more babies.
| Do you have any evidence that wealthier men have more
| babies?
|
| In fact, it's quite the opposite. There is a strong inverse
| correlation between wealth and number of babies. Both
| globally [1] and in the US [2]. There is some data that you
| can seek out that will suggest the trend is reversed in
| some first-world countries in the past couple of years, but
| that's no where near enough time to draw conclusions.
|
| Is there real evidence that men with greater "health"
| (besides the obvious, of, say, having a crippling disease)
| or "reputation" have more children?
|
| I'm sorry, but this sounds like "women only chose alpha
| males" junk to me.
|
| 1. https://en.wikipedia.org/wiki/Income_and_fertility
|
| 2. https://www.statista.com/statistics/241530/birth-rate-
| by-fam...
| ninetyninenine wrote:
| Per my hypothesis I never said wealthier men should have
| more babies. Birth control is a factor here.
|
| Women do marry and prefer richer men. Hypergamy is
| scientifically true, you can look it up if you want. But
| birth control changes the outcome even though hypergamy
| is an influencing factor.
|
| In addition I said health and reputation are factors. So
| a man with good health but low wealth has one positive
| factor in his favor.
|
| I feel your entire reply is rude and over the top.
| Calling my statement junk is not conducive to discussion.
| SamBam wrote:
| Ok, fair enough, I didn't mean to be rude. It's just that
| it sounds a lot like stuff that people who push fairly
| sexist stuff say.
|
| The thread is about evolution, and sexual selection in
| the context of evolution generally implies having an
| evolutionary fitness. I missed the part about birth
| control, since then we're not really talking about
| whether sexual selection is having a role in human
| evolution.
|
| In the context of sexual selection affecting evolutionary
| fitness, it seems clear that there is an inverse
| relationship between wealth and number of offspring.
|
| I am not sure if there are any scientific studies
| purporting to link "reputation" and either marriage or
| offspring. Do you know of any?
| dekhn wrote:
| I believe we are currently measuring recent functional
| selection on humans and it's non-zero. That is, empirically
| you are incorrect.
| red-iron-pine wrote:
| no one is having babies mon ami. birth rates are declining.
|
| it's not about killing people before reproductive age, it's
| about absolute numbers of offspring born. dying before
| reproducing ensures that number stays 0, but you can still
| hit sexual maturity and not reproduce.
|
| plus there is a fertility window -- after 50 most humans,
| male or female, ain't having kids (a handful of rockstar
| types whelping babies at 80 notwithstanding).
|
| there is a TON of meaningful pressure in our environment,
| like the inability to have a living wage reducing how many
| Gen Z's are marrying and having kids.
| thaumasiotes wrote:
| > it's not about killing people before reproductive age,
| it's about absolute numbers of offspring born.
|
| Technically, it's about averaging offspring (weighted by
| your genetic contribution to them) across _all of time_. If
| you have 30 children, and all of them starve to death
| before reproducing, you 've reproduced less than your
| neighbor with the one child and one grandchild.
|
| But that's impossible to calculate, so mostly we just have
| to work with number of children. This detail, though, is
| something you might want to keep in mind when looking at
| reports of "effective population" in the past. Any actual
| population in the far past who end up being wiped out in
| the middle past are excluded from the "effective
| population" that we calculate.
|
| https://en.wikipedia.org/wiki/Effective_population_size
| _DeadFred_ wrote:
| That's what the build up of plastics in our testicles are
| for.
| toasterlovin wrote:
| If there's a fertility gradient based on heritable traits
| then there is evolution happening.
| steve_adams_86 wrote:
| This simply isn't how evolution works. There's no way to be
| "beyond" it. It's an inevitable facet of populations of
| living organisms.
|
| If a population used genetic engineering to collectively
| ensure their genetics didn't change, no mutations, no other
| populations involved, then... I guess? Otherwise, there is
| this staggering multitude of influences.
|
| Living longer and reproducing longer is a huge weight on the
| scales of evolution. Why does anyone need to die early for it
| to work?
| immibis wrote:
| Does everyone have two children?
| JumpCrisscross wrote:
| > _Humans are beyond evolution_
|
| Empirically false [1]. The median artery is a poignant
| example from the industrial era [2].
|
| [1] https://en.wikipedia.org/wiki/Recent_human_evolution#Earl
| y_M...
|
| [2] https://en.wikipedia.org/wiki/Median_artery
| BurningFrog wrote:
| Men will evolve to manage sperm banks and fertility clinics.
| MrLeap wrote:
| After the high profile grossness with those, you'd think
| every person using those services would do a paternity test
| just in case.
| tpierce89 wrote:
| I would like to see if there is a correlation between Sleep Apnea
| cases and nose shape to determine if there is a link between
| humans living in an area they are not adapted to and how that
| affects their ability to breathe normally.
| woolion wrote:
| I suspect the impact would be extremely small compared to BMI,
| so it would be likely that there would be a link because of
| some dependent variables.
| oremolten wrote:
| I bet there is also a large correlation with computer/phone
| neck and posture
| hammock wrote:
| Ok, what about looking at nose shape of diaspora that have
| historically (multigenerationally) high BMI? Not an expert
| but might suggest Inuit, some Pacific Islanders, Maori, west
| Africans maybe. How are their noses shaped and anything that
| might help with apnea?
| ninetyninenine wrote:
| Sleep apnea usually comes from the back of the throat. It's not
| a nose thing as much.
| BurningFrog wrote:
| People probably sleep in very similar conditions in all
| climates.
| davidw wrote:
| Going to use this as a comeback next time my wife makes a
| comment: "I'm just well-adapted to certain climates, so there!"
| boxed wrote:
| West African, but not East African? That seems like an enormous
| problem in itself.
| nickdothutton wrote:
| Also there is a relatively new (5800 years ago) mutation somehow
| related to brain development, the ASPM gene. The mutation is
| somehow advantageous to the individual, but we don't yet know
| exactly why/how.
|
| https://en.wikipedia.org/wiki/ASPM_(gene)#Evolution
| InfiniteLoup wrote:
| There is a rather distinct type of nose which I've only ever
| observed with people of Ukrainian ethnic descent.
|
| Now I wonder if that is in fact some type of adaptation to local
| climate because the people of the surrounding areas don't seem to
| have that nose shape to the same extent.
| SamBam wrote:
| If I'm reading this right, the hypothesis seems to be that in
| drier climates, humans need longer noses (simplifying) to
| increase the humidity of the air to an optimal level.
|
| Did the authors propose a counter-evolutionary pressure, to favor
| a shorter nose in more humid environments?
|
| It's possible that the mechanism would be as simple as "it
| requires more resources to maintain a longer nose," but I'm also
| wondering if they suggested anything.
| indulona wrote:
| so indeed jews are the spawn of satan since there must be quite
| dry in hell.
| Sam6late wrote:
| On a slightly related issue, I noticed that my nose gets
| bigger,in my photos, it turned out it was mostly irritation
| swelling due to pollution, while in a Nordic country with cleaner
| air quality, I noticed that is back to normal. And now I am
| always checking iqair.com- and it says:"PM2.5 concentration is
| currently 3.6 times the World Health Organization annual PM2.5
| guideline value.
| idunnoman1222 wrote:
| Do people with bigger noses have fewer upper respiratory tract
| infections or no?
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