Abstract

Aim: The role of ecological specialisation in shaping biogeographic and evolutionary patterns remains unresolved. To date, few studies have quantitatively examined consumer niche breadth at a global scale. We describe global biogeographic and diversification patterns of specialisation, measured using trophic and thermal niches, for a highly diverse assemblage of consumers: reef fishes. First, we investigated the confluence of specialisation with global biogeographic patterns in species richness and reef area. Then, we tested whether these patterns could be explained by differences in diversification rates and geographic ranges. Location: Tropical reefs across the globe. Time Period: Present. Major Taxa Studied: Reef fishes. Methods: To estimate trophic specialisation, we compiled a comprehensive dataset on reef fish trophic interactions from published gut content analyses, including dietary information for ~5000 individuals across 387 fish species. We used the geographic range of species and global temperature data to estimate thermal specialisation of reef fishes. We used distributional data and Bayesian Structural Equation Modelling to test for the correlation between biogeographic variables, species richness, and the prevalence of trophic or thermal specialisation in reef fish assemblages. Moreover, we used linear models to test for a correlation between reef fish diversification rates, geographic range, and their degree of trophic and thermal specialisation. Results: Our analysis suggests that species richness is positively associated with trophic specialisation in reef fishes, with isolated and species-depauperate communities supporting assemblages dominated by trophic and thermal generalists. We found no effect of trophic and thermal specialisation on diversification rates and geographic range at the species level. Main Conclusions: Our findings indicate that specialisation is favoured in large, biodiversity-rich regions, but specialists might show lower capacity for colonisation, with lower representation on smaller, isolated reefs. These results contribute to our understanding of the dynamics shaping fish biogeography on coral reefs.

Document Type

Journal Article

Date of Publication

5-1-2025

Volume

34

Issue

5

Funding Information

CNPq (310906/2023-7) / Mission Atlantic Project, funded by the European Union's Horizon Research and Innovation Program (862428) / Branco Weiss Fellowship Society in Science / PSL Junior Fellowship / Edith Cowan University

School

Centre for Marine Ecosystems Research / School of Science

Creative Commons License

Creative Commons Attribution-No Derivative Works 4.0 License
This work is licensed under a Creative Commons Attribution-No Derivative Works 4.0 License.

Publisher

Wiley

Identifier

Alexandre C. Siqueira: https://orcid.org/0000-0001-7970-4024

Comments

This is an Author's Accepted Manuscript of: Delecambre, Z., Morais, R. A., Siqueira, A. C., Costesec, E. P., Dubé, C. E., Floeter, S. R., Friedlander, A. M., Leprieur, F., Letourneur, Y., Nunes, L. T., Casey, J. M., & Parravicini, V. (2025). Ecological specialisation of reef fishes peaks in global biodiversity hotspots. Global Ecology and Biogeography, 34(5), e70050. https://doi.org/10.1111/geb.70050

Available for download on Friday, May 15, 2026

Share

 
COinS
 

Link to publisher version (DOI)

10.1111/geb.70050