Zombie Snails! Imagine, if you will, the everyday life of a garden snail. Prone to drying out, you avoid the desiccating rays of the sun as you slither in the shadows under dense foliage, eating anything chewable you find in your slimy path. One day, you catch a whiff of fresh bird droppings; to you,
a delicious and nutritious meal. Days later, however, you start to feel strange - at least as strange as your incredibly simple nervous system can muster - and against all logic, you feel attracted to the hot, bright daylight your kind has spent millions of years hiding from. You go about your snaily business as you always would, but this time, you're completely exposed, both to the sun and to the eyes of hungry birds. Your foul tasting slime has taught most avians that snails are an unappetizing meal, but unfortunately for you, you no longer look like a normal snail.
Those droppings you ate were swarming with the eggs of the parasitic flatworm, Leucochloridium. Invading your simple little gastropod brain, the worms have completely rewired your behavior, and with their colorful, pulsing "brood sacs" crammed into your eye-stalks, your head now resembles a couple of fat, juicy insect larvae - every bird's favorite.
You'll likely survive your eyestalks being ripped off, and eventually, your entire face will grow back...as will the parasites. You're lucky evolution never granted you the intellect to comprehend your new existence, enslaved by a worm in your brain to have your eyes chewed off again and again.
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