Find research datasets worth reusing

opencc-zeroApr 2024View details →

Data from: Genetic analysis of red deer (Cervus elaphus) administrative management units in a human-dominated landscape - patterns of genetic diversity, population structure and gene flow

Red deer (Cervus elaphus) throughout central Europe are impacted by different anthropogenic activities including habitat fragmentation, selective hunting, and translocations. This has substantial influences on genetic diversity and the long-term conservation of local populations of this species. Here we use genetic samples from 480 red deer individuals to assess the genetic diversity and differentiation of the 12 administrative management units located in Schleswig Holstein, the northernmost federal state in Germany. We applied multiple analytical approaches and show that the history of local populations (i.e., translocations, culling of individuals outside of designated red deer zones, and anthropogenic infrastructures) has led to comparably low levels of genetic diversity. The mean expected heterozygosity was below 0.6 and we observed on average 4.2 alleles across 12 microsatellite loci. Effective population sizes below the recommended level of 50 were estimated for multiple local populations. Our estimates of genetic structure and gene flow show that red deer in northern Germany are best described as a complex network of asymmetrically connected subpopulations, with high genetic exchange among some local populations and reduced connectivity of others. Genetic diversity was also correlated with population densities of neighboring management units. Based on these findings, we suggest that connectivity among existing management units needs to be considered in the practical management of the species, which means that some administrative management units should be managed together, while the effective isolation of other units needs to be mitigated.

opencc-zeroOct 2023View details →

First insights into population structure and genetic diversity versus host specificity in trypanorhynch tapeworms using multiplexed shotgun genotyping

Theory predicts relaxed host specificity and high host vagility should contribute to reduced genetic structure in parasites while strict host specificity and low host vagility should increase genetic structure. Though these predictions are intuitive, they have never been explicitly tested in a population genomic framework. Trypanorhynch tapeworms, which parasitize sharks and rays (elasmobranchs) as definitive hosts, are the only order of elasmobranch tapeworms that exhibit considerable variability in their definitive host specificity. This allows for unique combinations of host use and geographic range, making trypanorhynchs ideal candidates for studying how these traits influence population-level structure and genetic diversity. Multiplexed shotgun genotyping (MSG) datasets were generated to characterize component population structure and infrapopulation diversity for a representative of each trypanorhynch suborder: the ray-hosted Rhinoptericola megacantha (Trypanobatoida) and the shark-hosted Callitetrarhynchus gracilis (Trypanoselachoida). Adults of R. megacantha are more host-specific and less broadly distributed than adults of C. gracilis, allowing correlation between these factors and genetic structure. Replicate tapeworm specimens were sequenced from the same host individual, from multiple conspecific hosts within and across geographic regions, and from multiple definitive host species. For R. megacantha, population structure coincided with geography rather than host species. For C. gracilis, limited population structure was found, suggesting a potential link between degree of host specificity and structure. Conspecific trypanorhynchs from the same host individual were found to be as, or more, genetically divergent from one another as from conspecifics from different host individuals. For both species, high levels of homozygosity and positive FIS values were documented.

opencc-zeroNov 2021View details →

Populations restored using regional seed are genetically diverse and similar to natural populations in the region

Ecological restoration and plant re-introductions aim to create plant populations that are genetically similar to natural populations to preserve the regional gene pool, yet genetically diverse to allow adaptation to a changing environment. For this purpose, seeds for restoration are increasingly sourced from multiple populations in the target region. However, it has only rarely been tested whether using regional seed indeed leads to genetically diverse restored populations which are genetically similar to natural populations. We used single nucleotide polymorphism (SNP) markers to investigate genetic diversity within and differentiation among populations of Centaurea jacea and Betonica officinalis on restored and natural meadows in the White Carpathians, Czech Republic. The restoration took place 20 years ago using regional seeds propagated from a mix of multiple regional source populations. We included original regional seeds in our analysis to compare the restored populations with their origin (only in C. jacea). Additionally, we analysed conventional seeds without certified origin because these would have constituted a common alternative for restoration seeding in the absence of regional seeds. The differentiation between restored and natural populations (mean pairwise FST = 0.018 in Centaurea and 0.021 in Betonica) was similar to the differentiation among natural populations (FST = 0.023 and 0.021), and the restored populations were slightly more genetically diverse than the natural populations. In addition, restored populations were relatively similar to their origin, the regional seeds (FST = 0.015). In contrast, conventional seeds were strongly differentiated from all regional populations (FST = 0.100 and 0.059, in Centaurea and Betonica, respectively) and harboured substantially lower genetic diversity. We also found signs of gene flow via pollen or seed dispersal from natural to restored populations but not vice versa. Policy implications. Regionally sourced seeds can produce genetically diverse populations at natural levels of genetic differentiation.

opencc-zeroJun 2022View details →

Assessing population structure and genetic diversity in U.S. Suffolk sheep to define a framework for genomic selection

Long-term sustainability of breeds depends on having sufficient genetic diversity for adaptability to change, whether driven by climatic conditions or by priorities in breeding programs. Genetic diversity in Suffolk sheep in the U.S. was evaluated in four ways: 1) using genetic relationships from pedigree data [(n=64,310 animals recorded in the U.S. National Sheep Improvement Program (NSIP)]; 2) using molecular data (n=304 Suffolk genotyped with the OvineHD BeadChip); 3) comparing Australian (n=109) and Irish (n=55) Suffolk sheep to those in the U.S. using molecular data; and 4) assessing genetic relationships (connectedness) among active Suffolk flocks (n=18) in NSIP. By characterizing genetic diversity, a goal was to define the structure of a reference population for use for genomic selection strategies in this breed. Pedigree-based mean inbreeding level for the most recent year of available data was 5.5%. Ten animals defined 22.8% of the current gene pool. The effective population size (Ne) ranged from 27.5 to 244.2 based on pedigree and was 79.5 based on molecular data. Expected (HE) and observed (HO) heterozygosity were 0.317 and 0.306, respectively. Model-based population structure included 7 subpopulations. From Principal Component Analysis, countries separated into distinct populations. Within the U.S. population, flocks formed genetically disconnected clusters. A decline in genetic diversity over time was observed from both pedigree and genomic-based derived measures with evidence of population substructure as measured by FST. Using these measures of genetic diversity, a framework for establishing a genomic reference population in U.S. Suffolk sheep engaged in NSIP was proposed.

opencc-zeroJul 2022View details →

Genetic diversity and differentiation of populations of Anthyllis vulneraria along elevational and latitudinal gradients

The abundant centre model (ACM) predicts that the suitability of environmental conditions for a species decreases from the centre of its distribution towards its range periphery and consequently its populations will become scarcer, smaller and more isolated, resulting in lower genetic diversity and increased differentiation. However, little is known about whether genetic diversity shows similar patterns along elevational and latitudinal gradients with similar changes in important environmental conditions. Using microsatellite markers we studied the genetic diversity and structure of 20 populations each of Anthyllis vulneraria along elevational gradients in the Alps from the valleys to the elevational limit (2500 m), and along a latitudinal gradient (2500 km) from Central Europe to the range margin in northern Scandinavia. Both types of gradients corresponded to a 11.5 °C difference in mean annual temperature. Genetic diversity strongly declined and differentiation increased with latitude in line with the predictions of the ACM. However, as population size did not decline with latitude and genetic diversity was not related to population size in A. vulneraria, this pattern is not likely to be due to less favourable conditions in the North, but due to serial founder effects during the post-glacial recolonization process. Genetic diversity was not related to elevation, but we found significant isolation by distance along both gradients, although the elevational gradient was shorter by orders of magnitude. Subarctic populations differed genetically from alpine populations indicating that the northern populations did not originate from high elevational Alpine ones. Our results support the notion that postglacial latitudinal colonization over large distances resulted in a larger loss of genetic diversity than elevational range shifts. The lack of genetic diversity in subarctic populations may threaten their long-term persistence in the face of climate change, whereas alpine populations could benefit from gene flow from low-elevation populations.

opencc-zeroJul 2022View details →

Nuclear genetic diversity and structure of Anastrepha ludens wild populations evidenced by microsatellite markers

The Mexican fruit fly, Anastrepha ludens is an important pest that causes widespread damage to a number of fruit crops in Mexico. The Sterile Insect Technique (SIT) is commonly used for its control. However, the existence of natural barriers can give rise to a population structure in neutral loci and possibly behavioral or adaptive traits that interfere with SIT. For this reason, it is important to understand the genetic diversity and structure of A. ludens populations and to better understand the evolutionary ecology and population processes in view of possible expansions and possible host shifts due to climate change. We genotyped nine nuclear DNA (nDNA) microsatellite loci among fruit fly populations collected from five biogeographic areas within Mexico, Mexican Plateau, the Northeastern Coastal Plain, the Pacific Coast, the Gulf Coast of Mexico, the Soconusco and a laboratory strain. The nuclear genetic diversity was moderate (from He = 0.34 to He = 0.39) within the wild mexfly population. We found that populations were clustered in three genetic groups (K=3). The diversity and genetic structure of A. ludens are produced by environmental and geological conditions as well as local conditions like anthropogenic perturbation which would produce population expansion and the existence of possible predators that would affect the population density. Gene flow showed recent migration among populations. The laboratory strain showed less diversity than the wild samples. Large values of current and ancestral population size suggest high resistance to climatic changes, probably due to biological attributes, such as its polyphagous, multivoltine and high dispersal characteristics. In particular ecosystem fragmentation and perturbation as well as the existence of new plant hosts all of which would probably increase the abundance of flies.

opencc-zeroAug 2022View details →

Population dynamics of Amazonian floodplain forest species support spatial variation on genetic diversity but not range expansions through time

Aim: We tested if historical demographic changes of populations occurring on the floodplains of a major Amazon Basin tributary could be associated with range expansions from upper and middle sections of the river, following the establishment of widespread river-created environments during the Late Pleistocene and Holocene. Location: Solimões River, Western Amazon, South America. Taxon: Myrmoborus lugubris, Thamnophilus cryptoleucus and Myrmotherula assimilis. Methods: We explored spatial patterns of genetic diversity and connectivity among sampled localities using thousands of Ultra-Conserved Elements. Range expansions were tested with alternative methods. We quantified habitat preference for the analyzed species to test whether the occupation of dynamic habitats could predict spatial patterns of genetic diversity. Results: Our study did not support shared population range expansions related to historical regionalized changes in habitat availability. We found considerable variation in the spatial distribution of the genetic diversity between studied taxa, and that species with higher levels of specialization to dynamic environments have a more heterogeneous distribution of genetic diversity and reduced levels of gene flow across space. Main conclusions: Our results suggest that demographic expansions along the Solimões River might be linked to spatially homogeneous oscillation in the distribution of floodplain environments, promoting effective population size changes but not range expansion. We found that habitat specificity might be a good predictor of population connectivity along the Amazonian floodplains.

opencc-zeroSep 2022View details →

Pollinator data from: Pollinator movement activity influences genetic diversity and differentiation of spatially isolated populations of clonal forest herbs

In agricultural landscapes, forest herbs live in small, spatially isolated forest patches. For their long-term survival, their populations depend on animals as genetic linkers that provide pollen- or seed-mediated gene flow among different forest patches. However, whether insect pollinators serve as genetic linkers among spatially isolated forest herb populations in agricultural landscapes remains to be shown. Here, we used population genetic methods to analyze: (A) the genetic diversity and genetic differentiation of populations of two common, slow-colonizing temperate forest herb species (Polygonatum multiflorum (L.) All. and Anemone nemorosa L.) in spatially isolated populations within three agricultural landscapes in Germany and Sweden and (B) the movement activity of their most relevant associated pollinator species, i.e., the bumblebee Bombus pascuorum (Scopoli, 1763) and the hoverfly Melanostoma scalare (Fabricus, 1794), respectively, which differ in their mobility. We tested whether the indicated pollinator movement activity affected the genetic diversity and genetic differentiation of the forest herb populations. Bumblebee movement indicators that solely indicated movement activity between the forest patches affected both genetic diversity and genetic differentiation of the associated forest herb P. multiflorum in a way that can be explained by pollen-mediated gene flow among the forest herb populations. In contrast, movement indicators reflecting the total movement activity at a forest patch (including within-forest patch movement activity) showed unexpected effects for both plant-pollinator pairs that might be explained by accelerated genetic drift due to enhanced sexual reproduction. Our integrated approach revealed that bumblebees serve as genetic linkers of associated forest herb populations, even if they are more than 2 km apart from each other. No such evidence was found for the forest-associated hoverfly species which showed significant genetic differentiation among forest patches itself. Our approach also indicated that a higher within-forest patch movement activity of both pollinator species might enhance sexual recruitment and thus diminishes the temporal buffer that clonal growth provides against habitat fragmentation effects.

opencc-zeroSep 2022View details →

Data from: Linking environmental stability with genetic diversity and population structure in two Atlantic Forest palm trees

Spatial patterns of biodiversity in the Atlantic Forest of Brazil are well characterized. However, there is no consensus on the biological processes underlying these patterns, and multiple competing hypotheses have been proposed, several of which center on climatic stability. Here, we ask if Late Quaternary climatic stability predicts contemporary population structure and genomic-level diversity in two palm species: Syagrus botryophora and S. pseudococos (Arecaceae) We first use species occurrence data to model the distribution of suitable environments in 62 time-slice climate projections over the last 120 thousand years, and summarize stability over that period. We then use >25,000 RADseq-generated SNPs to i) describe the spatial patterns of genomic variation in both species, ii) test how well genomic variation is explained by isolation by distance and by the environmental resistance imposed by historical instability (isolation by resistance) and iii) test for a correlation between genetic diversity and historical stability. The contemporary range of S. botryophora has been relatively stable over the last 30 thousand years and there are two isolated regions of high stability for S. pseudococos. The genomic data recovers a clear pattern of isolation by distance in S. botryophora and two structured populations in S. pseudococos. Consequently, the contribution of isolation by resistance to overall genetic structure is much higher in S. pseudococos. Genetic diversity is not significantly correlated with historical stability in either species. Based on the concordance between historical stability and genetic structure, Late Quaternary climate stability may have maintained population connectivity within S. botryophora and promoted intraspecific divergence in S. pseudococos. Conversely, historical stability does not seem to be driving spatial patterns of genetic diversity. This study supports the primary role of climatic stability in determining spatial population structure, but not genetic diversity, in the Atlantic Forest.

opencc-by-4.0Dec 2021View details →

Dataset for "Genetic diversity and population structure of a wide Pisum spp. core collection."

Silico-DArT and SNP datasets of the IAS pea core collection. Each file contain key information of the molecular markers used to establish the population structure and genetic diversity of the IAs pea core collection.

opencc-zeroMay 2024View details →

Data from: Small but connected islands can maintain populations and genetic diversity under climate change

In response to the striking effects of environmental change, conservation strategies often include the identification of conservation areas that can effectively maintain vulnerable species. Consequently, identifying system-specific conditions that maintain the demographic and genetic viability of species of conservation concern is essential. Connectivity plays a critical role in the persistence of populations. Islands have been model systems to understand connectivity and metapopulation processes and have emerged as particularly favorable targets for conservation. While islands can be isolated from mainland disturbances, it is unknown what degree of isolation is necessary to avoid unfavorable changes but remain sufficiently connected to maintain population viability. To test this question, we explored connectivity within the Apostle Islands, an archipelago of 22 islands within Lake Superior, by comparing historical and contemporary trends in ice bridge connectivity and by simulating the effect of reduced connectivity within this system. We developed a demographically informed individual-based model to explicitly test the role of connectivity to influence the persistence and genetic diversity of American marten (Martes americana), a forest carnivore at risk across its southern range boundary. We found that genetic diversity was resilient to moderate changes in ice cover, but a complete loss of connectivity resulted in rapid genetic erosion. Despite genetic erosion, populations persisted as long as nominal connectivity occurred between islands. Our work suggests that connectivity will decline, but martens would be resilient to moderate changes, and, in the short term, the Apostle Islands can act as a refuge along this species' southern range boundary. Identifying thresholds in connectivity that maintain populations but allow for isolation from disturbance will be necessary to identify suitable areas for species conservation across space and time.

opencc-zeroMay 2024View details →

Genome-wide single nucleotide polymorphisms reveal the genetic diversity and population structure of Creole goats from northern Peru

Goat farming constitutes a significant source of income for farmers in northern Peru. There is currently an absence of information about the genetics of Peruvian Creole goats that would enable us to understand their origins and genetic spread. The objective of this study was to estimate the genetic diversity of Creole goats from northern Peru using SNP markers. This study involved the collection of 192 male Creole goats from three key goat production regions in northern Peru. These goat samples were genotyped using the GGPGoat70k SNP panel. To explore the genetic influence of other breeds on Peruvian Creole goats, our dataset was combined with previously published SNP genotypes. External data set includes multiple breeds genotypes sampled from Argentina, Brazil, Spain, and Alpine breed from Italy, France, and Switzerland. After quality control 52,832 autosomal SNPs were used to assess genetic diversity in the Peruvian goats. For the population structure analysis of the merged data 20,513 common SNPs were used. Estimations for expected heterozygosity (He), observed heterozygosity (Ho), and inbreeding coefficient (FIS) were computed for the Peruvian groups. AMOVA, principal component analysis and ADMIXTURE were conducted to evaluate the population structure in the two data sets, Peru and merged. The results revealed a considerable genetic diversity, with Ho values ranging from 0.40 to 0.41 for the Peruvian sampling groups, and inbreeding coefficient was notably low for Peruvian goat. The population structure analysis demonstrated a distinction (p< 0.05) from other breeds. These findings suggest a level of genetic differentiation of the Peruvian goat population among other breeds, although further research is needed considering samples from other Peruvian areas. We expect this study will contribute to define genetic management strategies to prevent the loss of genetic diversity in Peruvian goat populations and for upcoming advancements in this field.

opencc-by-4.0Mar 2019View details →

Fig. 1 in Genetic diversity of Egyptian populations of the African Common Toad (Sclerophrys regularis, Reuss 1833)

Fig. 1. Map of the sampled localities.

opencc-zeroJun 2024View details →

Polyandry and non-random fertilisation maintain long-term genetic diversity in an isolated island population of adders (Vipera berus)

Conservation genetic theory suggests that small and isolated populations should be subjected to reduced genetic diversity i.e., heterozygosity and allelic diversity. Our 34 years study of an isolated island population of adders (Vipera berus) in southern Sweden challenges this notion. Despite a lack of gene flow and a yearly mean estimated reproductive adult population size of only 65 adult adders (range 12 to 171), the population has been able to maintain high levels of heterozygosity and allelic diversity similar to that observed in two mainland populations. Even a 14-year major "bottleneck" i.e., a reduction in adult adder numbers, encompassing at least four adder generations, did not result in any reduction in the island adders' heterozygosity and allelic diversity. Female adders are polyandrous, and fertilisation is non-random, which our empirical data and modelling suggest underpinning the island adders' ability to maintain a high level of heterozygosity. Our empirical results and subsequent modelling suggest that the positive genetic effects of polyandry in combination with non-random fertilisation, often overlooked in conservation genetic analyses, deserve greater consideration when predicting long-term survival of small and isolated populations.

opencc-zeroJul 2024View details →

An assemblage-level comparison of genetic diversity and population genetic structure between island and mainland ant populations

Island biotas provide unparalleled opportunities to examine evolutionary processes. Founder effects and bottlenecks, for example, typically decrease genetic diversity in island populations, while selection for reduced dispersal can increase population structure. Given that support for these generalities mostly comes from single-species analyses, assemblage-level comparisons are needed to clarify how (i) colonization affects the gene pools of interacting insular organisms, and (ii) patterns of genetic differentiation vary within assemblages of organisms. Here, we use genome-wide sequence data from ultraconserved elements (UCEs) to compare genetic diversity and population structure of mainland and island populations of nine ant species in coastal southern California with respect to genetic diversity and population structure. As expected, island populations (from Santa Cruz Island) had lower than expected heterozygosity and Watterson's theta compared to mainland populations (from the Lompoc Valley). Island populations, however, exhibited smaller genetic distances among samples, indicating less population subdivision and a higher capacity for dispersal compared to mainland populations. Within the focal assemblage, pairwise Fst values revealed pronounced interspecific variation in mainland-island differentiation, which increases with gyne body size. Our results reveal differences in genetic diversity and population genetic structure across an assemblage of interacting species, and illuminate general patterns of insularization in ants. Compared to single-species studies, our analysis of nine species pairs from the same island-mainland system offers a powerful approach to studying fundamental evolutionary processes.

Figure 1 in Unveiling the genetic diversity of bicolored-spined porcupines (Rodentia: Erethizontidae): a novel karyotype, population structuring, and evolutionary insights

Figure 1. Map of part of South America with collecting localities of C. bicolor specimens with sequences on the GenBank (Black circles), generated in the present study (triangle), others register of occurrences (white circles), and type locality (star). Gray area represents the Amazon Biome. ARG = Argentina, BOL = Bolivia, BRA = Brazil, PER = Peru.

Figure 4 in Unveiling the genetic diversity of bicolored-spined porcupines (Rodentia: Erethizontidae): a novel karyotype, population structuring, and evolutionary insights

Figure 4. Topology of median joining on top of the map showing the current separation of C. bicolor populations by the rivers Ucayali and Beni/Madre de Dios. Circles are haplotypes and its dimension are proportional to the number of shared sequences. Numbers in the segments connecting the circles are nucleotide substitutions and black circle is the median vector. For haplotypes localities see figure 2. BOL = Bolivia, BRA = Brazil, PER = Peru.

Figure 3 in Unveiling the genetic diversity of bicolored-spined porcupines (Rodentia: Erethizontidae): a novel karyotype, population structuring, and evolutionary insights

Figure 3. Maximum likelihood phylogenetic tree. Symbols near nodes represent Bootstrap values: black circles (90-100%), white circles (80-89%), white squares (70-79%), black square (66%). BOL = Bolivia, BRA = Brazil, COL = Colombia, ECU = Ecuador, GUF = French Guiana, MEX = Mexico, PAR = Paraguay, PER = Peru.

Figure 2 in Unveiling the genetic diversity of bicolored-spined porcupines (Rodentia: Erethizontidae): a novel karyotype, population structuring, and evolutionary insights

Figure 2. Conventional stained karyotypes of Coendou (Sphiggurus) bicolor male LBCE21287 (above) and female LBCE21289 (below) from Brazilian Acre state with 2n = 52 and FN = 82. The X and Y are sexual chromosomes.