| 1. |
- Abalaka, Jacinta, et al.
(författare)
-
Genetic diversity and population structure of the range restricted rock firefinch Lagonosticta sanguinodorsalis
- 2015
-
Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 16:2, s. 411-418
-
Tidskriftsartikel (refereegranskat)abstract
- Understanding the degree of genetic population differentiation is important in conservation genetics for inferring gene flow between populations and for identifying small and isolated threatened populations. We evaluated the genetic variation within and between three populations of the rock firefinch (Lagonosticta sanguinodorsalis), a range restricted firefinch endemic to Nigeria and Cameroon. The populations were closely located (c. 100 km apart) within the species' core distribution in Central Nigeria. We found that the populations had similar levels of gene diversities (H (E) ) and low but significant inbreeding coefficients (F (IS) ). Despite the short distance between populations there was a weak but significant population structure, which indicates that the populations are somewhat isolated and affected by drift within the species' core distribution in Nigeria. The knowledge of the genetic status of the rock firefinch will serve as a foundation to future studies to help understand population demography and for managing and maintaining viable populations.
|
|
| 2. |
- Andersson, Anastasia, et al.
(författare)
-
Complex genetic diversity patterns of cryptic, sympatric brown trout (Salmo trutta) populations in tiny mountain lakes
- 2017
-
Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 18:5, s. 1213-1227
-
Tidskriftsartikel (refereegranskat)abstract
- Intraspecific genetic variation can have similar effects as species diversity on ecosystem function; understanding such variation is important, particularly for ecological key species. The brown trout plays central roles in many northern freshwater ecosystems, and several cases of sympatric brown trout populations have been detected in freshwater lakes based on apparent morphological differences. In some rare cases, sympatric, genetically distinct populations lacking visible phenotypic differences have been detected based on genetic data alone. Detecting such cryptic sympatric populations without prior grouping of individuals based on phenotypic characteristics is more difficult statistically, though. The aim of the present study is to delineate the spatial connectivity of two cryptic, sympatric genetic clusters of brown trout discovered in two interconnected, tiny subarctic Swedish lakes. The structures were detected using allozyme markers, and have been monitored over time. Here, we confirm their existence for almost three decades and report that these cryptic, sympatric populations exhibit very different connectivity patterns to brown trout of nearby lakes. One of the clusters is relatively isolated while the other one shows high genetic similarity to downstream populations. There are indications of different spawning sites as reflected in genetic structuring among parr from different creeks. We used > 3000 SNPs on a subsample and find that the SNPs largely confirm the allozyme pattern but give considerably lower F (ST) values, and potentially indicate further structuring within populations. This type of complex genetic substructuring over microgeographical scales might be more common than anticipated and needs to be considered in conservation management.
|
|
| 3. |
- Bererhi, Badreddine, et al.
(författare)
-
Inconsistent inbreeding effects during lizard ontogeny
- 2019
-
Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 20:4, s. 865-874
-
Tidskriftsartikel (refereegranskat)abstract
- Reported effects of inbreeding vary among taxa and may depend on a number of factors, including what trait is measured, temporal variability, parental effects, or life history stage. To understand the effects of inbreeding during early life history stages, we estimated the effects of individual-level heterozygosity on hatching success and first year survival in a Swedish population of sand lizards (Lacerta agilis) over a period of almost a decade, using over 4000 eggs, 400 clutches, and over 3000 juveniles. Heterozygosity had a positive effect on hatching success, in standardized laboratory conditions, but no effect on first year survival. Also, both of these measures of viability varied across the years of the study, demonstrating the importance of temporal heterogeneity in pre and post-hatching conditions. Finally, we identified both paternal and maternal identity effects on hatching success. Thus, we show that selection on heterozygosity was not consistent across developmental life stages, emphasizing the need of considering a number of ontogenic stages, as well as potential parental and environmental effects, when studying the effects of heterozygosity on viability in natural populations.
|
|
| 4. |
- Bodare, Sofia, et al.
(författare)
-
Fine- and local- scale genetic structure of Dysoxylum malabaricum, a late-successional canopy tree species in disturbed forest patches in the Western Ghats, India
- 2017
-
Ingår i: Conservation Genetics. - : SPRINGER. - 1566-0621 .- 1572-9737. ; 18:1, s. 1-15
-
Tidskriftsartikel (refereegranskat)abstract
- Dysoxylum malabaricum (white cedar) is an economically important tree species, endemic to the Western Ghats, India, which is the world's most densely populated biodiversity hotspot. In this study, we used variation at ten nuclear simple sequence repeat loci to investigate genetic diversity and fine scale spatial genetic structure (FSGS) in seedlings and adults of D. malabaricum from four forest patches in the northern part of the Western Ghats. When genetic variation was compared between seedlings and adults across locations, significant differences were detected in allelic richness, observed heterozygosity, fixation index (F (IS)), and relatedness (P < 0.05). Reduced genetic diversity and increased relatedness at the seedling stage might be due to fragmentation and disturbance. There was no FSGS at the adult stage and FSGS was limited to shorter distance classes at the seedling stage. However, there was clear spatial genetic structure at the landscape level (< 50 km), regardless of age class, due to limited gene flow between forest patches. A comparison of the distributions of size classes in the four locations with published data from a more southern area, showed that large trees (diameter at breast height, DBH, > 130 cm) are present in the southern sacred forests but not in the northern forest reserves. This pattern is likely due to stronger harvesting pressure in the north compared to the south, because in the north there are no cultural taboos regulating the extraction of natural resources. The implications for forest conservation in this biodiversity hotspot are discussed.
|
|
| 5. |
- Höglund, Jacob, et al.
(författare)
-
Low MHC variation in isolated island populations of the Natterjack toad (Bufo calamita)
- 2015
-
Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 16:4, s. 1007-1010
-
Tidskriftsartikel (refereegranskat)abstract
- We studied variation at the class II gene of the major histocompatibility complex (MHC) in Natterjack toad populations (Bufo [Epidalea] calamita) on islands off the west coast of Sweden. These isolated populations have previously been shown to exhibit low levels of neutral genetic variation. On seven investigated islands we found only two different MHC alleles, indicating that the genetic variation at this locus is also low. The two alleles were found in all populations, although in one population there was only a single heterozygous individual. The Swedish toads showed similar low levels of MHC variation as revealed by previously published data from populations in northern Europe. We did not find a correlation between MHC and neutral genetic variation (as determined by AFLP). However, our findings show that reduced genetic variation in the Swedish Natterjack toads is not restricted to neutral markers, but is likewise reflected at the MHC.
|
|
| 6. |
- Jansson, Mija, et al.
(författare)
-
Genetic contribution from a zoo population can increase genetic variation in the highly inbred wild Swedish wolf population
- 2015
-
Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 16:6, s. 1501-1505
-
Tidskriftsartikel (refereegranskat)abstract
- The Swedish wolf population (Canis lupus) descends from five individuals and is isolated and highly inbred with an average inbreeding coefficient of 0.27. In addition, inbreeding depression has led to reduced litter size and a high frequency of spinal disorders. To achieve the management goal of reducing the mean level of inbreeding, introductions into the wild population from a zoo conservation breeding program have been proposed by authorities. We used pedigree data of the wild and zoo populations to evaluate the extent to which the captive population can contribute genetic variation to the wild one. We measure genetic variation as founder alleles and founder genome equivalents. The two populations have three founders in common, but in spite of this common ancestry, our results show a potential to almost double genetic variation from 11.2 to 21.1 founder alleles. Similarly, the number of founder genome equivalents in the wild population can increase from the present 1.8 to 3.2, but this requires that almost 50 % of the wild gene pool consists of genes from the zoo population. Average kinship in the joint zoo and wild population is 0.15, which is above the management target of 0.1. Genetic contribution from the zoo has the potential to improve, but not solve, the genetically precarious situation of the wild population.
|
|
| 7. |
- Kireta, Dona, et al.
(författare)
-
Disentangling the evolutionary history of three related shrub species using genome-wide molecular markers
- 2019
-
Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 20:5, s. 1101-1112
-
Tidskriftsartikel (refereegranskat)abstract
- Understanding population genetic structure provides insight into historic population connectivity, and is largely driven by migration, population size, and species life history. During the last glacial maximum, sea levels around the biogeographically interesting, but poorly studied, South Australian coastal plains and geosyncline were thought to be sufficiently low that three prominent peninsulas (Fleurieu, Yorke, Eyre) and a large offshore island (Kangaroo Island) formed a continuous landmass. However, the degree to which population genetic structure in this region has been shaped by biogeography remains largely untested. Here, we use genome-wide SNP data from three Goodenia shrub species with contrasting growth forms to assess how historical and contemporary processes have shaped population genetic structure. These species occur commonly throughout South Australia and are used extensively in revegetation. The two woody species (Goodenia varia, G. ovata) displayed low genetic differentiation across the southern parts of the peninsulas and island, reflecting historical landscape connectivity. The third more-herbaceous species (G. amplexans) displayed higher genetic structure across the land features, reflecting contemporary disconnectivity. Kangaroo Island and the southern Flinders Ranges had relatively high genetic diversity, providing further evidence that they were important putative Pleistocene refugia. We demonstrate that historic changes in landscape and possible migration to and from refugia, have shaped the population genetic structure in these closely related shrubs, which may have been influenced by contemporary factors and small population sizes. We highlight the importance of using multi-species designs when studying historical population connectivity in understudied regions of the world.
|
|
| 8. |
- Lopes, Fernando, et al.
(författare)
-
Fine-scale matrilineal population structure in the Galapagos fur seal and its implications for conservation management
- 2015
-
Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 16:5, s. 1099-1113
-
Tidskriftsartikel (refereegranskat)abstract
- Females of many pinniped species generally exhibit strong fine-scale philopatry, but it is unclear over what spatial scale this behavior may translate into genetic population structure. We conducted a population genetic survey in the Galapagos fur seal, Arctocephalus galapagoensis, an endangered pinniped endemic to a small geographic range in the northwest of the Galapagos archipelago. To assess patterns of genetic diversity levels and population differentiation, we analyzed part of the mitochondrial control region (mtDNA) and 18 microsatellites DNA markers. We detected similar levels of genetic diversity to many other pinniped species (h = 0.86, pi = 0.012, A = 7.44) despite severe anthropogenic exploitation in the nineteenth century and recurrent population crashes due to recent climatic perturbations associated with El Nio Southern Oscillation events. We further found remarkably strong fine-scale matrilineal population structure, with 33.9 % of the mtDNA variation being partitioned among colonies separated by as little as 70 km swimming distance. In contrast, population structure inferred from nuclear markers was weak. Our findings provide further evidence that natal philopatry can translate into fine-scale genetic population structure in highly mobile species. We discuss the relevance of our results for the fine-scale conservation management of this species with a very restricted geographic range.
|
|
| 9. |
- Meyer-Lucht, Yvonne, et al.
(författare)
-
Adaptive and neutral genetic differentiation among Scottish and endangered Irish red grouse (Lagopus lagopus scotica)
- 2016
-
Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 17:3, s. 615-630
-
Tidskriftsartikel (refereegranskat)abstract
- Studying patterns of intra-specific genetic variation among populations allows for a better understanding of population structure and local adaptation. However, those patterns may differ according to the genetic markers applied, as neutral genetic markers reflect demographic processes and random genetic drift, whereas adaptive markers also carry the footprint of selection. In combination, neutral and adaptive genetic markers permit to assess the relative roles of drift and selection in shaping population structure. Among the best understood adaptive genetic loci are the genes of the major histocompatibility complex (MHC). We here study variation and differentiation at neutral SNP markers and MHC class II genes in red grouse (Lagopus lagopus scotica) from Ireland and Scotland. Irish red grouse populations are fragmented and drastically declining, but red grouse are abundant in Scotland. We find evidence for positive selection acting on the MHC genes and variation in MHC gene copy numbers among Irish individuals. Furthermore, there was significant population differentiation among red grouse from Ireland and Scotland at the neutral SNP markers (F-ST = 0.084) and the MHC-BLB genes (F-ST: BLB1 = 0.116, BLB2 = 0.090, BLB3 = 0.104). Differentiation at the MHC-BLB1 was significantly higher than at the neutral SNP markers, suggesting that selection plays an important role in shaping MHC variation, in addition to genetic drift. We speculate that the observed differentiation pattern might be due to local adaptation to different parasite regimes. These findings have strong conservation implications and we advise against the introduction of Scottish red grouse to supplement Irish populations.
|
|
| 10. |
- Moussy, Caroline, et al.
(författare)
-
The genetic structure of the European breeding populations of a declining farmland bird, the ortolan bunting (Emberiza hortulana), reveals conservation priorities
- 2018
-
Ingår i: Conservation Genetics. - : Springer. - 1566-0621 .- 1572-9737. ; 19:4, s. 909-922
-
Tidskriftsartikel (refereegranskat)abstract
- Anthropogenic activities, such as agricultural intensification, caused large declines in biodiversity, including farmland birds. In addition to demographic consequences, anthropogenic activities can result in loss of genetic diversity, reduction of gene flow and altered genetic structure. We investigated the distribution of the genetic variation of a declining farmland and long-distance migratory bird, the ortolan bunting Emberiza hortulana, across its European breeding range to assess the impact of human-driven population declines on genetic diversity and structure in order to advise conservation priorities. The large population declines observed have not resulted in dramatic loss of genetic diversity, which is moderate to high and constant across all sampled breeding sites. Extensive gene flow occurs across the breeding range, even across a migratory divide, which contributes little to genetic structuring. However, gene flow is asymmetric, with the large eastern populations acting as source populations for the smaller western ones. Furthermore, breeding populations that underwent the largest declines, in Fennoscandia and Baltic countries, appear to be recently isolated, with no gene exchange occurring with the eastern or the western populations. These are signs for concern as declines in the eastern populations could affect the strength of gene flow and in turn affect the western populations. The genetic, and demographic, isolation of the northern populations make them particularly sensitive to loss of genetic diversity and to extinction as no immigration is occurring to counter-act the drastic declines. In such a situation, conservation efforts are needed across the whole breeding range: in particular, protecting the eastern populations due to their key role in maintaining gene flow across the range, and focussing on the northern populations due to their recent isolation and endangered status.
|
|
| 11. |
- Norén, Karin, et al.
(författare)
-
Red foxes colonizing the tundra : genetic analysis as a tool for population management
- 2017
-
Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 18:2, s. 359-370
-
Tidskriftsartikel (refereegranskat)abstract
- Climate change accelerates biodiversity alterations in northern ecosystems. A prevalent example is that tundra regions are invaded by boreal species. This impacts negatively on native species through competition, predation and transmission of zoonoses. Scandinavian red foxes (Vulpes vulpes) have emerged into the tundra and have altered the structure and function of the tundra community. For instance, they threaten persistence of the endangered Swedish Arctic fox (Vulpes lagopus). County board administrations implement control of the tundra red foxes, but little is known about the underlying expansion dynamics. A broad-scale study revealed high connectivity where northern areas were supplemented with red foxes from surrounding population. However, red fox expansion is most prevalent in tundra regions and the fine-scaled expansion dynamics in these areas have not yet been disseminated. With the aim of identifying the invasive pathways of tundra red foxes, we present microsatellite data for 205 Swedish red foxes and mitochondrial sequence variation in 102 foxes sampled across the historical boreo-nemoral distribution and recently colonized tundra regions. Genetic structuring was low with high levels of ongoing, asymmetric dispersal from surrounding boreal zones into tundra habitats causing high genetic admixture. In both tundra and boreo-nemoral regions, inter-individual relatedness decreased with increasing geographic distance and data suggests male-biased dispersal patterns. Overall, fine-scaled expansion patterns were affected by multiple factors and we discuss its implications for future red fox management.
|
|
| 12. |
- Nota, Kevin, et al.
(författare)
-
Metabarcoding-based dietary analysis of hen harrier (Circus cyaneus) in Great Britain using buccal swabs from chicks
- 2019
-
Ingår i: Conservation Genetics. - : Springer. - 1566-0621 .- 1572-9737. ; 20:6, s. 1389-1404
-
Tidskriftsartikel (refereegranskat)abstract
- The hen harrier is a heavily persecuted bird of prey in Great Britain since its diet includes Red grouse, a game bird shot in driven and walked-up grouse shooting. Unlike walked-up shooting where shooters walk up moors and flush grouse with dogs, in driven grouse shooting the grouse are driven by beaters towards static shooters. Driven grouse moors (DGMs) are increasingly being managed to sustain high densities of Red grouse intensifying a long-standing conservation conflict between conservationists and grouse moor keepers. A metabarcoding approach was used with degenerate universal cytochrome oxidase I and cytochrome b primers along with hen harrier blocking primers. A novel sampling method was used to detect prey in buccal swab samples from chicks from broods across Great Britain from both managed and unmanaged moorland habitats. This resulted in detection of 62 species of prey across 51 broods with Meadow pipit, Red grouse, Wren, Skylark, and voles being most frequently detected. Frequency of occurrence data and species accumulation curves reveal high incidence of Red grouse and low prey species richness in the diet of hen harriers in DGMs but low incidence of Red grouse and high prey species richness in walked-up and unmanaged moors. Waders were only detected within walked-up and unmanaged moors and not within DGMs where they have been reported to occur at high densities. Regional species detected included endemic species such as the Orkney vole seen only in Orkney. This study represents the first metabarcoding-based dietary analysis in a raptor using buccal swabs.
|
|
| 13. |
- Rózsa, Jani, et al.
(författare)
-
Effects of a range expansion on adaptive and neutral genetic diversity in dispersal limited Hazel grouse (Bonasa bonasia) in the French Alps
- 2016
-
Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 17:2, s. 401-412
-
Tidskriftsartikel (refereegranskat)abstract
- Biogeographic range expansions, when related to dispersal limitation, may have counter intuitive effects on genetic diversity. At range margins the relative roles of demographic changes, connectivity and genetic diversity need to be integrated for a successful assessment of population viability. Historically the Hazel grouse (Bonasa bonasia) in France was found in the north of the French Alps and also in a disjunct population in the nearby Jura Mountains. The species has recently undergone a range expansion in a north to south axis in the Alps. Local population size estimates and migration patterns during expansion have previously been studied. In this study, we performed genotyping at neutral (microsatellite) and adaptive (MHC) genetic markers in Hazel grouse. We compared diversity and differentiation (FST and DEST) at three sampling localities along the expansion axis in the French Alps and Jura, as well as at two sampling localities in Sweden, where the population has had a long-term continuous and stable distribution. Strong serial founder effects were found between the French localities, resulting in stronger isolation further south, with a relatively high neutral differentiation (pair-wise FST = 0.117). However, the loss of adaptive diversity MHC was slight. No adaptive differentiation (MHC DEST = −0.015) was observed, thus, the French localities can be considered uniform units with regard to MHC diversity, a criterion to treat populations in these localities as a management unit.
|
|
| 14. |
|
|
| 15. |
- Tison, Jean-Luc, et al.
(författare)
-
Population structure and recent temporal changes in genetic variation in Eurasian otters from Sweden
- 2015
-
Ingår i: Conservation Genetics. - : Springer Science and Business Media LLC. - 1566-0621 .- 1572-9737. ; 16:2, s. 371-384
-
Tidskriftsartikel (refereegranskat)abstract
- The Eurasian otter (Lutra lutra) population in Sweden went through a drastic decline in population size between the 1950s and 1980s, caused mostly by anthropogenic factors such as high hunting pressure and the introduction of environmental toxic chemicals into the otter's habitats. However, after the bans of PCBs and DDT in the 1970s, the population began to recover in the 1990s. This study compares microsatellite data across twelve loci from historical and contemporary otter samples to investigate whether there has been a change in population structure and genetic diversity across time in various locations throughout Sweden. The results suggest that otters in the south were more severely affected by the bottleneck, demonstrated by a decline in genetic diversity and a shift in genetic composition. In contrast, the genetic composition in otters from northern Sweden remained mostly unchanged, both in terms of population structure and diversity. This suggests that the decline was not uniform across the country. Moreover, our analyses of historical samples provide an overview of the level of genetic variation and population structure that existed prior to the bottleneck, which may be helpful for the future management and conservation of the species.
|
|
| 16. |
|
|
