Freshwater mussels: The Bait and Switch
Male mussels release sperm into the water, which females capture downstream. Larvae hatch inside the females’ shells but must then attach to a fish to grow. To lure fish, mother mussels wave appendages that look like worms, crayfish or other bait. Some emit a smell of rotting flesh to attract scavenger fish. When fish approach, the mussels shoot the larvae onto the fish.
(Image: Mussels. Source: tlindenbaum/Flickr via a Creative Commons license.)