4 ms·

From the author summary: > We find that variation in both nares width and alar base width appear to have experienced accelerated divergence across human popula

• kseistrup 2y ago
  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 2y ago
    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 2y ago
      Yay free proteins!
    • kseistrup 2y ago
      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 2y ago
        Andean Indians are known for fairly wide, prominent noses. They also have massive thoraxes and lung capacity.
      • 0xEF 2y ago
        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 2y ago
          > 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 2y ago
          Honestly, all this makes zero difference if you're not frail or in advanced age. I regularly experience winter temperatures of -30°C or lower (-40° is not infrequent), and it really doesn't matter how you breathe.
• cyrillite 2y ago
  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 2y ago
  > 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 2y ago
    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 2y ago
      Pretty sure the best hunter gets the most kids on average.
      • DiscourseFan 2y ago
        Source?
        • BurningFrog 2y ago
          Just common sense. The guy who brings home the most food will have the most surviving children. He will also be very attractive to women.
          • DiscourseFan 2y ago
            It was also "common sense" not so long ago that the earth was the center of the universe. You're engaging with me disingenuously.
• DrScientist 2y ago
  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 2y ago
  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 2y ago
  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.