Regional-Scale Assembly Rules and Biodiversity of Coral Reefs

TLDR

Tropical reef fishes and corals display predictable taxonomic patterns across the Indian and Pacific Oceans, with species richness varying along gradients but overall composition remaining within a narrow range. Regional reef biodiversity is primarily driven by shallow‑water habitat availability; once habitat is accounted for, latitude and longitude have little residual effect, and low‑diversity regions are especially vulnerable to human impacts such as global warming, underscoring the need for multinational management.

Abstract

Tropical reef fishes and corals exhibit highly predictable patterns of taxonomic composition across the Indian and Pacific Oceans. Despite steep longitudinal and latitudinal gradients in total species richness, the composition of these key taxa is constrained within a remarkably narrow range of values. Regional-scale variation in reef biodiversity is best explained by large-scale patterns in the availability of shallow-water habitat. Once habitat area is accounted for, there is surprisingly little residual effect of latitude or longitude. Low-diversity regions are most vulnerable to human impacts such as global warming, underscoring the urgent need for integrated management at multinational scales.