Cepaea nemoralis

Shell patterns in the common European land snail (Cepaea nemoralis) are determined genetically, and include variation in both ground color (yellow darkening to green) and presence or absence and extent of banding. Studies show that visual predators such as thrushes preferentially consume the less cryptic snails in any environment. Light, banded snails are more common in grasslands, whereas dark, un-banded snails are more common in dimly-lit woodlands.