• Question: How do flies walk on the ceiling?

    Asked by EmilyE on 11 May 2020.
    • Photo: Jennifer Cookman

      Jennifer Cookman answered on 11 May 2020:

      I guess some sort of sticky feet but not sticky enough to keep them there longterm! This will involve a google search 😉

    • Photo: Aisling Ryan

      Aisling Ryan answered on 11 May 2020:

      This is a very interesting question! I don’t know a lot about flies myself, so I had to google this.
      I found that in order to walk on the ceiling (or on a wall) flies have a few tricks they use!
      First of all they have feet that are soft and padded. This means that a large amount of their foot can touch the ceiling at one time. They also have sticky areas on their feet that have lots of sticky little hairs. Some scientists in Germany found out that a liquid similar to glue comes out of these hairs, which is what allows the fly to stick to surfaces. Of course flies also need to be able to remove their foot from the ceiling so they don’t get stuck there forever! For this, flies have special claws on their feet that they use to help push their foot from the ceiling, or twist it (like a dance!), or peel their foot off.
      Thanks for helping me learn some interesting facts about flies!!

    • Photo: Tommy Hayden

      Tommy Hayden answered on 11 May 2020:

      I always thought they had suction pads on the end of their legs but not so according to google. Apparently they have adhesive pads with small hairs that “produce a glue-like substance made of sugars and oils”. They can use claws on the end of their legs to help them push off. They can’t fly upside down so they barrel roll back to a position in which they can fly

      Thanks for helping me learn something new!

    • Photo: Simon Spichak

      Simon Spichak answered on 11 May 2020:

      Flies might seem like a bit of a nuisance but I think they are super cool! Sometimes I wish I could walk on the ceiling but unfortunately I am not a fly. Now unfortunately I can’t walk on ceilings because the gravity of the Earth pulls me back down to the ground. The force of gravity is related to the mass of an object, so simply put that there is a lot more force pulling me down, than on a fly.

      Now as some of the others have mentioned, flies have a sticky substance on their feet that lets them stick to things, but of course not so sticky that they get stuck! Since flies have a much smaller mass than people, they don’t need to resist nearly as much force as we would!

    • Photo: Aruna Chandrasekar

      Aruna Chandrasekar answered on 11 May 2020:

      Adding on to the amazing answers :
      “Sticky feet” of flies are used as a base concept for better adhesion. The sticky substance in the flies’ feet is much stronger than our commonly used synthetic adhesives.

      A similar effect of “sticky fingers” is observed when humans enter the water. The wrinkles in our hands and feet create a similar effect for better gripping in water.

    • Photo: Katherine Benson

      Katherine Benson answered on 12 May 2020:

      I think some other lovely scientists have answered this already, but I believe there’s a few ways that insects achieve this, some have lots and lots of tiny bristles or hairs on their feet, which allow them to find microscopically small ridges in smooth surfaces to grip onto, and others use a sticky substance to stop them falling off.

    • Photo: Sonia Lenehan

      Sonia Lenehan answered on 12 May 2020:

      Great question EmilyE. I did not know the answer to this and now because you asked and so many amazing scientists answered I do!