Has this ever happened to you? There’s a fly in the house, buzzing around you, so you go to the cabinet to get the swatter. But as soon as you start wielding it, the little bastard disappears. You set it down, and now he’s back, taunting you.
Ok so obviously flies don’t taunt, but do they have the capacity to recognize, even instinctually, that I’m holding a deadly weapon?
This isn’t silly - at all. Fly’s perception of the world is like bullet time to us. They can see something much faster than we can comprehend - that’s how they effortlessly move away from your swats
If you want to catch a fly, move to them VERY slowly and cup a hand or glass over them to capture them. If you move slow, it’s more difficult for them to perceive something is moving towards them - much like it’s difficult for us to perceive a rising tide or watch a plant grow.