Correlations between broad‐scale taxonomic and genetic differentiations suggest a dominant imprint of historical processes on beta diversities. (9th April 2019)

• Record Type: Journal Article
• Authors: Robuchon, Marine; Leroy, Boris; Jézéquel, Céline; Hugueny, Bernard
• Is Part Of: Journal of biogeography. Volume 46:Number 5(2019:May)
• Page Start: 1083
• Page End: 1095
• Publication Date: 2019-04-09
• Subjects: β‐SGDC -- dispersal limitation -- distance decay -- drift -- environmental selection -- freshwater fishes -- historical processes -- macrogenetics -- Mantel tests -- multiple regression of distance matrices; Biogeography -- Periodicals; 578.09
• DOI: 10.1111/jbi.13559
• Languages: English
• ISSNs: 0305-0270

Abstract

Abstract: Aim: Dispersal limitation, environmental selection and drift are known to influence both taxonomic similarity between communities and genetic similarity between populations. However, disentangling the relative roles of these processes on spatial patterns of differentiation—whether regarding taxonomic differentiation (TD) between communities or genetic differentiation (GD) between populations—is challenging. Investigating whether spatial patterns of TD and GD are correlated (β‐SGDCs) is a promising approach to address this issue. Here, we investigated β‐SGDCs over broad spatial scales and 22 freshwater fish species to elucidate the processes shaping TD and GD between drainage basins. Location: Global scope, data mainly from Europe and North America. Taxon: Actinopterygii and Petromyzontiformes (freshwater fishes). Methods: We used Mantel tests to investigate the raw correlation between TD and GD. We carried out multiple regressions to characterize the effects of geographic distance (proxy of dispersal limitation), environmental distance (proxy of environmental selection) and pairwise harmonic mean area between basins (proxy of drift) on TD and GD taken separately. We then analyzed the correlation between the residuals of these two regressions with Mantel tests. Finally, we investigated whether the variation in β‐SGDC between species was related to species traits. Results: We detected an overall positive β‐SGDC, both for the raw and the residual correlations. This implies that, unmeasured effects, other than geographic distance, environmental distance and harmonic mean area, influence the β‐SGDC observed. Values of β‐SGDCs greatly varied between species, but this was not explained by any species traits. Main conclusions: Independently of the effects of geographic distance, environmental distance and harmonic mean area, the β‐SGDC we observed suggests that historical processes strongly shaped the patterns of TD and GD between basins. Consequently, TD may be an appropriate proxy to explain the influence of historical processes on GD.