Pest...

Man may be the fittest one to survive in the universe. He may rule the world, but he is nothing before mosquitoes and house flies. He can kill them by using pest control devices. But when he is left with empty hand, then he has to struggle a lot to control the pests like mosquitoes and house flies.
Man cannot bear the sound that appears when a mosquito is near one's ear. And when a house fly sits on someone, preferably wounds, you can taste hell a little bit. This shows the inability of man against the micro sized creatures. Man, the epitome of pride, should learn a lesson from this.