HORSEHAIR WORM Paragordius varius HOUSE CRICKET Acheta domesticus The house cricket loses its will—and its life—to the horsehair worm. Larvae of the parasite infiltrate the cricket when it scavenges dead insects, then grow inside it. The cricket is terrestrial, but the adult stage of the worm’s life cycle is aquatic. So when the mature worm is ready to emerge, it alters the brain of its host, driving the cricket to abandon the safety of land and take a suicidal leap into the nearest body of water. As the cricket drowns, an adult worm emerges, sometimes a foot in length.
