Mosquitoes and annoying flies suck...
Spiders and bats ROCK!!
Indeed Mosquitoes and flies suck. Between two species, they carry and spread 50 known human diseases wherever they go. So yes, thank heaven for providing spiders and bats (avian flycatchers and gnat catchers eat them, as well) to whittle down their numbers. They're little sanitation crew members with an appetite for all that's bad for human beings.
