Why do we have Easter Bunnies?

http://en.wikipedia.org/wiki/Easter_Bunny

The hare was a popular motif in medieval church art. In ancient times it was widely believed (as by Pliny, Plutarch, Philostratus and Aelian) that the hare was a hermaphrodite.[3][4][5] The idea that a hare could reproduce without loss of virginity led to an association with the Virgin Mary, with hares sometimes occurring in illuminated manuscripts and Northern European paintings of the Virgin and Christ Child. It may also have been associated with the Holy Trinity, as in the three hares motif,[3][6] representing the “One in Three and Three in One” of which the triangle or three interlocking shapes such as rings are common symbols. In England, this motif usually appears in a prominent place in the church, such as the central rib of the chancel roof, or on a central rib of the nave. This suggests that the symbol held significance to the church, and casts doubt on the theory that they may have been masons’ or carpenters’ signature marks.[7]

Marshmallow bunnies and candy eggs in an Easter basket

Eggs, like rabbits and hares, are fertility symbols of antiquity. Since birds lay eggs and rabbits and hares give birth to large litters in the early spring, these became symbols of the rising fertility of the earth at the March Equinox