Eli5: Why does a fly keep running into walls at high speeds?

Question

Its like midnight and i keep hearing a fly run into my walls and buzz loudly. Why and or what makes them do this?

In: Biology

Answer 1

Flies are dumb. Their tiny brains can’t process much more than “food! I will eat this” and “here is no food, let me fly elsewhere” (and “here is another fly I can mate with”). Flying into a wall doesn’t hurt them in the same way as [ants don’t get hurt from falling](https://www.reddit.com/r/explainlikeimfive/comments/1e9m1uw/eli5_why_do_insects_like_ants_not_get_broken_legs/). It might be too dark to see the wall, and they can’t remember that it is there.