Ant Sight is a Fallout 3 perk. It is one of two possible perks you can get from Doctor Lesko for helping him get rid of the fire ant nest guardians during the Those! quest, Ant Might is the other.
This perk grants +1 Perception and +25% Fire Resistance.
“Your body has been genetically enhanced with the perception and flame resistance of the GrayditchFire Ants! Your Perception has increased by 1 and you are now 25% resistant to fire”— In-game description, Fallout 3