• CrazyLikeGollum@lemmy.world
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      7 days ago

      The nostrils are connected to the throat through the sinuses as are the ear canals. Topologically making them all part of the same mouth-anus throughole.

      • itslilith@lemmy.blahaj.zone
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        7 days ago

        Not true, topolgically the route

        left nostril -> sinus -> right nostril

        is another hole. So is

        any nostril -> sinus -> mouth.

        ears have the eardrum, so they don’t count.

        For the more formal definitions of topological holes, look up Betti numbers, I think there’s a VSauce video about it? For humans, the number of holes is at least 3 (but I’m sure I’m missing many more holes). Unless you’re missing the entire septum.