• Reddfugee42@lemmy.world
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    2 months ago

    This is (fortunately) why there’s a maximum size on insects. The environment is less oxygen rich today than in the eras of giant insects in the past. They reach a size where oxygen can’t penetrate deeply enough onto their bodies.

    • excral@feddit.org
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      2 months ago

      It’s all based on a very fundamental mathematical law: if you increase the size of something, the volume increases with the third power while the surface area increases with the second power. An insect twice as large would be 8x as heavy and need 8x as much oxygen but 4x as much surface area.

      That’s also the reason why insects are as strong as they are. The strength of a muscle scales primarily with the cross section area of it, which again scales with the second power. So if you’d increase the weight of an ant by a factor 10,000,000 (e.g. 5mg to 50kg), the expected strength would increase by 10,000,000^(2/3) ≈ 46,400. If it could lift 10x it’s weight at the original size, it could now only lift about 4.6% of it’s weight

  • IndescribablySad@threads.net@sh.itjust.works
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    2 months ago

    So if I understand you correctly, if I remove my lungs, I’m a bee? My aunt had lung cancer, so they’ll probably kill me, anyway. I’ll report back on the results.

    Edit: left wiggle, right wiggle, left wiggle, buzz

    • tahoe@lemmy.world
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      2 months ago

      No because you’re likely too big (no offense) :(

      I think insects have little holes all over their bodies, in which air gets inside by itself through some physics shenanigans. It doesn’t need to be actively sucked in like with lungs, it just happens because they’re so small.

      This method doesn’t scale up though since if you’re bigger, you need more air, and having little holes all over your body won’t cut it. Thats when you know you need lungs, and that’s why you don’t see insects the size of a dog these days (thankfully).

      There used to be times in the Earth’s history (Carboniferous) where the air’s composition was different though, and since it had more oxygen in it, insects could grow a lot larger.

      • Metz@lemmy.world
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        2 months ago

        Fun fact: Cutaneous respiration (aka “Skin breathing”) is something we humans do too. But it accounts only for 1% to 2% of our oxygen input.

        However, the cornea of ​​our eyes doesn’t have its own blood vessels to supply it. Therefore, it relies on direct gas exchange with the environment—in other words, skin respiration.

        Our eyes breath like bees.

      • joelfromaus@aussie.zone
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        2 months ago

        It’s been a long time since I’ve seen it but the movie Mimic had bugs that had grown to the size of a human and taken on a vaguely human form in order to hunt us.

        The movie used the reasoning that the bugs had developed basic lungs which enabled them to grow past the limits of their usual breathing apparatus.

        No point to make here, I just remember it being cool that they put a small amount of thought into why the bugs could grow to human proportions.