Is the reason that flies can perceive things faster because their brains are smaller? We know that flies can perceive changes in the world around them up to seven times faster than a human - we appear slow to them. I'm wondering how this is possible. Is it just that information travelling is limited by the speed of light, and it has a shorter distance to travel across a flies brain? Or is there some metabolic or other biological reason for this? (It would be great to speed up a human's brain - but I'm sure there are a million reasons why that is not possible). My question is: **Is the reason that flies can perceive things faster because their brains are smaller?**

Fly neurons aren't like human neurons. They have different nerves that transport signals faster than human nerves. So they can see your hand moving towards them faster than we can see for ourselves, which makes them able to avoid being squashed (most of the time).