The evolution of fishes on coral reefs: fossils, phylogenies, and functions

The last decade has seen major advances in our understanding of the evolutionary history of fishes on coral reefs. Where molecular and morphological phylogenies often clashed, they are now largely concordant, revealing clear patterns in reef fish evolution. This chapter synthesizes recent morphological and molecular evidence to address the evolution of both the forms and functions of fishes on coral reefs. Recent evidence allows us to identify six clear phases in the co-evolution of fishes and reefs. Over the past 400 million years, interactions between fishes and reefs have intensified from initial indifference to the complex ecosystems we see today, where coral reefs are highly dependent upon fish assemblages. Coral reefs, in turn, have acted as both cradles and refuges for fish lineages, underpinning both increased diversity and reduced extinctions. However, modern reefs are in decline. In many cases, coral reefs are losing crucial functions which have been established for tens of millions of years. Our understanding of how reefs functioned in the past offers a unique insight into the potential future of coral reefs.