Pattern of population structuring between Belgian and Estonian bumblebees

Abstract

Several population genetic studies investigated the extent of gene flow and population connectivity in bumblebees. In general, no restriction in gene flow is considered for mainland populations of common bumblebee species. Whether this assumption holds true for all species is not known. An assessment of bumblebee genetic structure in the context of their geographic distribution is needed to prioritize conservation and management needs. Here, we conducted a genetic study on seven bumblebee species occurring in Belgium and Estonia. Using 16 microsatellite markers, we investigated genetic diversity and population structuring in each species. This is the first study investigating population structuring of both declining and stable bumblebee species on both small and large geographic scales. Our results showed no or only low population structuring between the populations of the restricted and declining bumblebee species on both scales, while significant structuring was found for populations of the common species on the larger scale. The latter result, which may be due to human or environmental changes in the landscape, implies the need for the conservation of also widespread bumblebee species. Conservation strategies to improve gene flow and connectivity of populations could avoid the isolation and future losses of populations of these important species.

Winter activity unrelated to introgression in British bumblebee Bombus terrestris audax

“…Microsatellites are a useful and dependable tool for population genetics studies, with the ability to reliably resolve population structure, identify inbreeding and genetic diversity parameters (Maebe et al 2016(Maebe et al , 2018(Maebe et al , 2019a and have previously been used to find evidence of introgression in B. terrestris populations (Kraus et al 2011;Lemopoulos et al 2019). However, no technique is without limitation.…”

Level of Genetic Diversity in European Bumblebees is Not Determined by Local Species Abundance

“…= 1, p = 0.807, respectively). Marginal and conditional R 2 were similar for both A R and H E , 16.4% and 57.1% versus 15.2% and 55.7%, respectively (Nakagawa and Schielzeth, 2013). Post hoc tests were performed and showed significant differences in genetic diversity levels between the seven bumblebee species ( Table 5 and Supplementary Tables 2 and 3).…”

Assessment of genetic diversity and population structure of Eulaema nigrita (Hymenoptera: Apidae: Euglossini) as a factor of habitat type in Brazilian Atlantic forest fragments

“…These parameters were calculated using GenAlEx, version 6.5 Smouse 2006, 2012) and the diveRsity package in R (Keenan et al 2013), respectively. To test if habitat and relative abundance influenced genetic diversity (here, it refers only to allelic richness values) in each locality, linear mixed models were performed for allelic richness with the lmer function in the R package, lme4, version 1.1-10 (Bates et al 2015), as described in Soro et al (2017) and Maebe et al (2019aMaebe et al ( , 2019b. The model included habitat (considering the two physiognomies, rainforest and semi-deciduous forest), relative abundance as the fixed factors, and microsatellite loci as a random factor (Soro et al 2017;Barton 2020).…”

“…Gene flow among populations and the dispersal capacity of individuals are essential for the maintenance of genetic diversity over time, which is crucial for species survival (Maebe et al 2019a). Indeed, low levels of intraspecific genetic diversity can restrict the potential of species to adapt to environmental change (Frankham 2005;Zayed 2009;Habel et al 2014;Koch et al 2017;Maebe et al 2019aMaebe et al , 2019b. Among the effects of limited dispersal capability, populations that were previously but are no longer well-connected can attain significant population structure (Frankham 2005;Kokko and López-Sepulcre 2006;Zayed 2009;Maebe et al 2019b).…”

“…Indeed, low levels of intraspecific genetic diversity can restrict the potential of species to adapt to environmental change (Frankham 2005;Zayed 2009;Habel et al 2014;Koch et al 2017;Maebe et al 2019aMaebe et al , 2019b. Among the effects of limited dispersal capability, populations that were previously but are no longer well-connected can attain significant population structure (Frankham 2005;Kokko and López-Sepulcre 2006;Zayed 2009;Maebe et al 2019b). In contrast, high-dispersal rates can reduce drift effects and can lead to weak or absent population structure throughout large ranges (Frankham 2005;Kokko and López-Sepulcre 2006;Zayed 2009;Jha 2015;Maebe et al 2016;Maebe et al 2019b).…”