Animals traveling in large packs, shoals, or flocks, note Nicolas Rode and Eva Lievens, the French scientists who identified the manipulation, are assumed to do so for their own benefit—for example, to find mates, deter predators from attacking, or enhance foraging strategies. Rode and Lievens think it’s time to reexamine that assumption. Perhaps far more often than we realize, parasites might be herding their current hosts straight into the jaws of their next hosts.
