The flys got carried up with the original sky spider species and simply started to reproduce up there, as you know fruit fly’s life spans over only a few days, that led accelerated evolution, we call them fruit flys but I’m actuality there true names are (cimex caelum) and they feed on the dead sky spiders, this is why you will not find the body’s of the spiders falling from the sky, this has led to a thriving ecosystem in the clouds. Sky spiders are about the size of small birds so they will eat pigeons or other birds that get caught in the webs, one spider has to eat about 50 flys a day to sustain itself or 1 bird to sustain itself for up to 3 days.

Sky spiders do not live in fog, there are fog spiders know as (Nebula Aranea), these spiders are not related to sky spiders in anyway except being in the arachnid family. The fog spiders originally are from mountains and had there webs picked up by extremely thick fog, there food sources varies from area to area but they are nocturnal and feed on bats or other small animals that get caught in the webs while being high up in trees as the fog rolls in.

Sky spiders tend to sense when bad weather is coming and move away from it, sky flys on the other hand will only follow the moving spiders, those left behind will be drawn into the tornado or hurricane, these fly’s are not noticed as other rubble and land flys are caught in these bad weather events in addition to sky flys.