By Janet Raloff
Acetaminophen has a powerful reputation for vanquishing pain. Wildlife-control specialists now report that the drug, the active ingredient in Tylenol and various other painkillers, can also relieve a longtime headache on Guam–brown tree snakes.
Since this marauder appeared on the island in the 1940s, the population density of the mildly venomous reptile has mushroomed to between 13,000 and 26,000 per square mile. Growing to more than 6 feet, a brown tree snake can swallow lizards, rabbits, puppies, piglets, and endangered birds. Several have even taken a bite out of a baby. Prowling overhead power lines, members of the species, Boiga irregularis, occasionally short-circuit wires and cause local blackouts.