What could be more seductive than bile salts? Well, for a sea lamprey, bile salts are about as good a come-on as come-ons come.
The sea lamprey, an invasive and destructive species in the Great Lakes, has evolved to use bile salts, acids brewed in their livers to assist in digestion, as pheromones. That's right: female sea lampreys are so enthusiastic about digestive aids that they'll squiggle upstream in pursuit of the enticing males producing them.
It’s an unusual preference — so unusual, new research shows, that not even the silver lamprey, a cousin to the sea lamprey but a native to the lakes, shares the sea lamprey's predilection. That’s a find that could help researchers develop traps that use the sea lamprey’s affinity for bile salts against it, while sparing the native lamprey species.