Predator-induced defense in a marine bryozoan.

Laboratory experiments showed that predation by both trophically specialized and generalized nudibranch species triggers rapid induction of defensive spines in the bryozoan Membranipora membranacea. Spines effectively control the pattern and extent of intracolony mortality caused by nudibranch predation. Previously found only in plants, rotifers, and cladocerans, consumer-induced defenses may be widespread among clone-forming or colonial taxa exposed to nonfatal encounters with predators.