Bacterial induction of settlement and metamorphosis in marine invertebrates

In reviewing the complexity and diversity of bacterial mediation of settlement and metamorphosis of marine invertebrate larvae, we give particular attention to settlement and metamorphosis on macroscopic biological substrata, focusing on bacteria-mediated induction of larvae by non-geniculate coralline algae. We consider the evolution of interactions between marine substrata, bacteria and larvae, and offer arguments as to why natural selection may favour these interactions. We speculate that bacterial induction of settlement and metamorphosis in marine invertebrates might be more widespread than is generally recognised.