Ecological traits shape genetic diversity patterns across the Mediterranean Sea: a quantitative review on fishes

Abstract

Aim We set out to identify the determinants of the variation in genetic diversity among fish species and test whether multi-species genetic diversity is randomly distributed in space.Location Mediterranean Sea.Methods We collected genetic diversity data from 39 published studies on Mediterranean fishes (31 species) along with the spatial coordinates of the sampling sites. We focused on microsatellite heterozygosity (151 data points) and mitochondrial haplotype diversity (201 data points). We used linear regressions to link genetic diversity and 11 ecological traits. We also tested for spatial autocorrelation and trends in the residuals.Results Among-species variation in microsatellite heterozygosity was explained by three ecological traits: vertical distribution, migration type and body length. Variation in mitochondrial haplotype diversity was also explained by vertical distribution and migration type, and by reproductive strategy (semelparity). However, vertical distribution and migration type showed opposite effects on microsatellites and mitochondrial diversity. After accounting for the effects of ecological traits, no spatial pattern was detected, except for one of the species considered.Main conclusions Ecological factors explain an important proportion of the among-species genetic diversity. These results suggest that life history strategies of the species influence the variation of microsatellite diversity indirectly through their effect on effective population size, while the spatial variations of genetic diversity seem to be too complex to be identified in our analysis. We found very different effects of traits on mitochondrial and nuclear DNA diversity, which can be explained by the specificities of mitochondrial DNA (absence of recombination, maternal inheritance and non-neutrality).

Is genomic diversity a useful proxy for census population size? Evidence from a species‐rich community of desert lizards

“…However, historical signals of demographic processes can weaken the relationship between census and effective population size, and thus the relationship between abundance and heterozygosity (Frankham, ). For example, range expansions or population bottlenecks can lead to reduced genetic diversity in marginal or founder populations, and consequently to decoupling from contemporary census population size (Banks et al, ; Charlesworth, ; Dalongeville, Andrello, Mouillot, Albouy, & Manel, ; Excoffier & Ray, ).…”

“…Recent studies have found strong relationships between ecological traits and genetic diversity at broad phylogenetic scales (e.g., across phyla; Romiguier et al, ); whether such patterns are also exhibited by more closely related species with similar life history traits remains equivocal (Ellegren & Galtier, ; Romiguier et al, ; Singhal, Huang, et al, ). Additionally, there is some evidence that microhabitat preference can limit dispersal and reduce within‐population genetic diversity (Brouat, Chevallier, Meusnier, Noblecourt, & Rasplus, ; Brouat, Sennedot, Audiot, Leblois, & Rasplus, ; Dalongeville et al, ; Khimoun et al, ; Pianka, ; Rabosky, Cowan, Talaba, & Lovette, ), but studies combining genome‐wide diversity estimates with ecological traits at the community level are rare.…”

A population genomics insight by 2b‐RAD reveals populations' uniqueness along the Italian coastline in Leptopsammia pruvoti (Scleractinia, Dendrophylliidae)

“…The maintenance of biodiversity at the local scale is critically dependent on the persistence of populations, influenced by self‐recruitment and propagule supply that are, to a wide extent, species‐specific processes. Connectivity itself, which depends on ocean circulation, life history traits, local population dynamics and spatial distribution of populations (Jonsson & Watson, ), is largely determined by specific population processes, and it is often inferred, for single species, at the metapopulation level (Dalongeville, Andrello, Mouillot, Albouy, & Manel, ).…”

“…Ideally, the design (location and size) of a robust MPA network should be supported by connectivity estimates for all the species of a given community to identify a consensus network which ensures enough connectivity to multiple species with different life history traits (Costantini, Ferrario, & Abbiati, ; Dalongeville et al, ; Jonsson & Watson, ; Pascual et al, ; Shanks, Grantham, & Carr, ). Recently, Melià et al () showed a novel methodological framework to synthesize species‐specific results into a set of community connectivity metrics and showed that spatiotemporal variation in magnitude and direction of the connections and interspecific differences in dispersing traits are key factors structuring community connectivity.…”

“…The maintenance of biodiversity at the local scale is critically dependent on the persistence of populations, influenced by selfrecruitment and propagule supply that are, to a wide extent, species-specific processes. Connectivity itself, which depends on ocean circulation, life history traits, local population dynamics and spatial distribution of populations (Jonsson & Watson, 2016), is largely determined by specific population processes, and it is often inferred, for single species, at the metapopulation level (Dalongeville, Ideally, the design (location and size) of a robust MPA network should be supported by connectivity estimates for all the species of a given community to identify a consensus network which ensures enough connectivity to multiple species with different life history traits (Costantini, Ferrario, & Abbiati, 2018;Dalongeville et al, 2016;Jonsson & Watson, 2016;Pascual et al, 2017;Shanks, Grantham, & Carr, 2003). Recently, Melià et al (2016) showed a novel methodological framework to synthesize species-specific results into a set of community connectivity metrics and showed that spatiotemporal variation in magnitude and direction of the connections and interspecific differences in dispersing traits are key factors structuring community connectivity.…”