Mechanisms of anti-predator behavior in the great ramshorn snail (Planorbarius corneus).

Like vertebrate animals, some invertebrates have been shown to exhibit fear- or anxiety-like behavior while in apparatus that allow choice between sheltered, darkened spaces and open, lit spaces. The behavioral mechanisms by which invertebrates accomplish this behavior, and whether those mechanisms are similar across species, has not been fully studied. Across three experiments, we investigated possible behaviors that Great Ramshorn snails (Planorbarius corneus) could use to accomplish fear behavior while in presence of the odor of a predatory fish.