 In the last apartment I had here in Bogota, on an almost daily basis, three or four houseflies would fly nonchalantly around in circles at the same point. Now, this was a couple of meters in from the dining room window, and the circumference of this lap was no more than a meter or so. And I've noticed this behavior elsewhere too, so it's not just in my old apartment, and it's not just here in Bogota. It's almost like they're engaged in the housefly equivalent of some light jogging or something.