Lin Ruian discovered a bizarre snail with flashing green and orange horns while hiking in Changhua County, Taiwan earlier this month. At first glance, this gastropod appeared to have “flashing lights” turned on inside it, but upon closer inspection this is occurring because its motor neurons and body have been seized by a parasitic flatworm, called the green-banded broodsac, which commonly uses snails as hosts to spread. Read more for a video and additional information.
Put simply, this parasite invades the snail’s eye stalks and creates a hypnotic pulsating pattern in order to imitate a caterpillar, thus attracting hunting birds when it forces the snail to go out into the open for them to spot. Birds will then eat the snail and the parasite can reproduce in their intestinal tract. The offspring is eventually transmitted through its feces and the cycle repeats.