When Nancy Beckage and I first met in Lynn Riddiford's laboratory at the University of Washington in the mid 1970s, the fields of parasitology, behavior, and endocrinology were thriving and far-flung--disciplines in no serious danger of intersecting. There were rumors that they might have some common ground: Behavioural Aspects of Parasite Transmission (Canning and Wright, 1972) had just emerged, with exciting news not only of the way parasites themselves behave, but also of Machiavellian worms that caused intermediate hosts to shift fundamental responses to light and disturbance, becoming in...