The historical biogeography of coral reef fishes: global patterns of origination and dispersal

Abstract

Abstract Aim To use recently published phylogenies of three major reef fish families to explore global patterns of species origin and dispersal over the past 65 million years. The key questions are: when and where did reef fishes arise, and how has this shaped current biodiversity patterns? Location Biogeographic reconstructions were performed on globally distributed reef fish lineages. Patterns of lineage origination and dispersal were explored in five major biogeographic regions: the East P acific, the A tlantic, the I ndian O cean, the I ndo‐ A ustralian A rchipelago hotspot, and the C entral P acific. Methods A dispersal, extinction and cladogenesis ( DEC ) model implemented in Lagrange was used to infer the most likely biogeographic scenarios at nodes on chronograms of three diverse reef fish families ( L abridae, P omacentridae, C haetodontidae). For the terminal branches ANOVA was used to compare patterns of origination on a regional and global scale. Patterns of origination and dispersal were examined within discrete time periods for the five biogeographic regions. Results Temporal examination of hypothetical ancestral lineages reveal a pattern of increasing isolation of the East P acific and A tlantic regions from the E ocene, and the changing role of the I ndo‐ A ustralian A rchipelago from a location of accumulating ranges in the P alaeo/ E ocene, a centre of origination in the M iocene, to extensive expansion of lineages into adjacent regions from the P liocene to Recent. Main conclusions While the East P acific and A tlantic have a history of isolation, the I ndo‐ A ustralian A rchipelago has a history of connectivity. It has sequentially and then simultaneously acted as a centre of accumulation ( P alaeocene/ E ocene onwards), survival ( E ocene/ O ligocene onwards), origin ( M iocene onwards), and export ( P liocene/Recent) for reef fishes. The model suggests that it was the proliferation and expansion of lineages in the I ndo‐ A ustralian A rchipelago (the C oral T riangle) during the M iocene that underpinned the current biodiversity in the I ndian and P acific O ceans.