A process‐based model supports an association between dispersal and the prevalence of species traits in tropical reef fish assemblages

Giulia Francesca Azzurra Donati,Jonathan Rolland,Fabien Leprieur,Loïc Pellissier,Valeriano Parravicini,Christian Heine,Michel Kulbicki,Oskar Hagen,Theo Gaboriau,Camille Albouy,Nicolas Salamin

doi:10.1111/ecog.04537

Abstract

Habitat dynamics interacting with species dispersal abilities could generate gradients in species diversity and prevalence of species traits when the latter are associated with species dispersal potential. Using a process‐based model of diversification constrained by a dispersal parameter, we simulated the interplay between reef habitat dynamics during the past 140 million years and dispersal, shaping lineage diversification history and assemblage composition globally. The emerging patterns from the simulations were compared to current prevalence of species traits related to dispersal for 6315 tropical reef fish species. We found a significant spatial congruence between the prevalence of simulated low dispersal values and areas with a large proportion of species characterized by small adult body size, narrow home range mobility behaviour, pelagic larval duration shorter than 21 days and diurnal activity. Species characterized by such traits were found predominantly in the Indo‐Australian Archipelago and the Caribbean Sea. Furthermore, the frequency distribution of the dispersal parameter was found to match empirical distributions for body size, PLD and home range mobility behaviour. Also, the dispersal parameter in the simulations was associated to diversification rates and resulted in trait frequency matching empirical distributions. Overall, our findings suggest that past habitat dynamics, in conjunction with dispersal processes, influenced diversification in tropical reef fishes, which may explain the present‐day geography of species traits.

Highlights

Specific regions of the globe host a disproportionally large fraction of extant biodiversity
Species richness differed across the major biogeographic regions, with one of the most evident contrasts observed between the Indo-Australian Archipelago (IAA), hosting simultaneously on average 1844 ± 331 distinct species and the Caribbean with ca. four fold less observed species richness (536 ± 56; Supplementary material Appendix 1 Fig. A3)
We found a consensus between high dispersal parameter values and observed large-bodied species distributions, where species character- Further, our results indicated that the frequency distribuized by a large body size were observed over the remotest reef tion of the dispersal parameter d matched the observed body structures, such as those of the Pacific islands (Fig. 2)

Summary

Introduction

Specific regions of the globe host a disproportionally large fraction of extant biodiversity. During the last ~100 million years, when many extant clades diversified, the continents and ocean basins position, topography and climatic conditions changed, influencing biodiversity dynamics (Leprieur et al 2016, Chalmandrier et al 2018, Rolland and Condamine 2019). Some regions, typically those at high latitude (Dynesius and Jansson 2000) or across different continents or marine basins (Pellissier et al 2014), suffered larger environmental changes, while others were more stable, thereby shaping speciation and extinction rates (Weir and Schluter 2007). There is growing interest to assess whether processes that have shaped species richness have influenced the spatial distribution of species traits

Methods

Results

Conclusion