You know how sometimes you have a fly in your house that you just can’t manage to get with that rolled up magazine? So you start slowly creeping up on it, thinking you’re going to catch it by surprise? Yeah, stop doing. It won’t work. It turns out the pesky buggers are so hard to hit because they’re basically Neo in The Matrix, and we’re just lowly Agent Smiths who are too slow to nab him.
The reason for their elusiveness, as we get to see in this video from the Science Channel, is due to the fact flies “see” time more slowly than we do. While a fly might only be flying at five miles per hour, “time perception depends on how rapidly an animals nervous system processes sensory information.” That perception is measured in hertz, and a fly’s measures at 250 hertz to our 60. So while we might be swinging as fast as we can, they are observing us in a way that makes us look much slower, and therefore easier to escape.
This is an evolutionary trait common in smaller animals (or ones that haven’t developed their own protective mechanism, like a turtle), a necessary survival trait to help escape larger predators. That evolutionary process is also responsible for why flies are able to react quickly to that vital sensory information, making them even harder to swat. To them, we are moving in slow motion and they are also much faster. Whoa.
It almost makes me feel bad about any fly I’ve ever managed to catch. It feels like I’ve robbed evolution of a cool little ninja. (It also makes me wonder how stupid I must have looked in slo-mo fits of frustration every time I’ve failed to catch a fly.)
Does this change the way you think about flies? Tell us below.
Image: Science Channel/YouTube