At work we somehow landed on the topic of how many holes a human has, which then evolved into a heated discussion on the classic question of how many holes does a straw have.

I think it’s two, but some people are convinced that it’s one, which I just don’t understand. What are your thoughts?

  • ccunning@lemmy.world
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    1 year ago

    How many holes does a rubber band have? A donut?

    Topologically a rubber band, a donut, and a straw have the same number of holes. The hole at either end of the straw is just a continuation of the same one hole.

        • andyburke@kbin.social
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          1 year ago

          Some people haven’t realized almost all animals are just tubes with various fancy shit glued on.

          Edit: including humans

            • Petrichor3345@kbin.social
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              1 year ago

              IIRC humans have 7 holes topologically (assuming both vsauce and my memory are correct). I’m not sure how many a flatworm would have, but I bet you could group animals by number of holes topologically, which might be interesting.

              • GreenPlasticSushiGrass@kbin.social
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                1 year ago

                Flatworms have a single opening that leads to a branching cavity (an incomplete digestive system). This means that the single opening is for both ingesting nutrients and expelling waste. While your mouth may be attached to your anus via the alimentary canal, I think it beats the hell out of having one multi-purpose opening, imho.

                • Petrichor3345@kbin.social
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                  1 year ago

                  Right, technically a human only has 1 hole for ingesting nutrients and expelling waste as well though, assuming you are talking about the mouth and anus. Does a flatworm have any other through holes though e.g. nostrils or tear ducts? I have no idea what the biology of a flatworm is haha.

                  • GreenPlasticSushiGrass@kbin.social
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                    1 year ago

                    No, gas exchange is by simple diffusion across the skin and gut. No ears or eyes per se, just some photosensitive cells in slight depressions on the head. Planaria are pretty simple as far as animals go.

      • kursis@kbin.social
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        1 year ago

        For normal people asshole would be continuation from mouth, but I don’t judge. You do you!

      • jclinares@kbin.social
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        1 year ago

        I assume that’s how OP’s debate of how many holes a human had ended up being about straws: someone argued that the mouth and the anus are just one hole

    • wanderingmagus@lemmy.world
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      1 year ago

      Take that cylinder and stretch it until it’s a cube with two square cutouts in it. Stretch in some of the inner walls. Now you have a house, with a door and a window. Now: does the house have two holes - a door and a window - or does it have one hole?

      • Th4tGuyII@kbin.social
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        1 year ago

        A straw’s “in” and “out” are completely arbitrary. You can flip a straw either way and it’d still work.

        Anything with a hole through it that isn’t perfectly 2D could have a “in” and “out” side. Your rubber band your doughnut only don’t have one because nobody ever thought to define one.