Love dart
Courting Helix aspersa snails in Ireland, the one on the right has a fired love dart embedded in its body.
Ronald Chase of McGill University said about the garden snail Helix aspersa, "I believe the myth of Cupid and his arrows has its basis in this snail species, which is native to Greece". He added, "The Greeks probably knew about this behavior because they were pretty good naturalists and observers."