Find research datasets worth reusing
Search datasets from major research repositories and use ShareScore to quickly assess how well each record supports discovery, access, and reuse.
90
datasets available to search
ShareScore release 0.9.0
Dataset results
90 results for “genetic drift”
Data from: Drift happens: molecular genetic diversity and differentiation among populations of jewelweed (Impatiens capensis Meerb.) reflect fragmentation of floodplain forests
Landscape features often shape patterns of gene flow and genetic differentiation in plant species. Populations that are small and isolated enough also become subject to genetic drift. We examined patterns of gene flow and differentiation among 12 floodplain populations of the selfing annual jewelweed (Impatiens capensis Meerb.) nested within four river systems and two major watersheds in Wisconsin, USA. Floodplain forests and marshes provide a model system for assessing the effects of habitat fragmentation within agricultural/urban landscapes and for testing whether rivers act to genetically connect dispersed populations. We generated a panel of 12,856 single nucleotide polymorphisms and assessed genetic diversity, differentiation, gene flow, and drift. Clustering methods revealed strong population genetic structure with limited admixture and highly differentiated populations (mean multilocus FST = 0.32, FST' = 0.33). No signals of isolation by geographic distance or environment emerged, but alleles may flow along rivers given that genetic differentiation increased with river distance. Differentiation also increased in populations with fewer private alleles (R2 = 0.51) and higher local inbreeding (R2 = 0.22). Populations varied greatly in levels of local inbreeding (FIS = 0.2 to 0.9) and FIS declined in smaller, more isolated populations. These results suggest that genetic drift dominates other forces in structuring these Impatiens populations. In rapidly changing environments, species must migrate or genetically adapt. Habitat fragmentation limits both processes, potentially compromising the ability of species to persist in fragmented landscapes.
Data for: Harvest and decimation affect genetic drift and the effective population size in wild reindeer
<p>Harvesting and culling are methods used to monitor and manage wildlife diseases. An important consequence of these practices is a change in the genetic dynamics of affected populations that may threaten their long-term viability. The effective population size (N<sub>e</sub>) is a fundamental parameter for describing such changes as it determines the amount of genetic drift in a population. Here, we estimate N<sub>e</sub> of a harvested wild reindeer population in Norway. Then we use simulations to investigate the genetic consequences of management efforts for handling a recent spread of chronic wasting disease, including increased adult male harvest and population decimation. The N<sub>e</sub>/N ratio in this population was found to be 0.124 at the end of the study period, compared to 0.239 in the preceding 14-year period. The difference was caused by increased harvest rates with a high proportion of adult males (older than 2.5 years) being shot (15.2 % in 2005-2018 and 44.8 % in 2021). Increased harvest rates decreased N<sub>e</sub> in the simulations, but less sex-biased harvest strategies had a lower negative impact. For harvest strategies that yield stable population dynamics, shifting the harvest from calves to adult males and females increased N<sub>e</sub>. Population decimation always resulted in decreased genetic variation in the population, with higher loss of heterozygosity and rare alleles with more severe decimation or longer periods of low population size. A very high proportion of males in the harvest had the most severe consequences for the loss of genetic variation. This study clearly shows how the effects of harvest strategies and changes in population size interact to determine the genetic drift of a managed population. The long-term genetic viability of wildlife populations subject to disease will also depend on the population impacts of the disease and how these interact with management actions.</p>
Fig. 2 in A coalescent-based estimator of genetic drift, and acoustic divergence in the Pteronotus parnellii species complex
Fig. 2 Echolocation call frequency by island by sex and its relation to mass on the call frequency (F(1, 49) = 0.435, P value = 0.512). The body dimensions. a Boxplots of echolocation frequency (summarizing 95% HPD of population differences in means for body mass was 10 calls/individual). Bayesian 95% high-probability density (HPD) of 0.89–2.29 g. c Call frequency as a function of forearm length. Anathe difference in call frequency means between Puerto Rico and Hislyses of covariance support little influence of forearm length on the call paniola was 5.2–6.0 kHz. b Call frequency as a function of body mass. frequency (F(1, 52) = 2.851, P value = 0.097). The 95% HPD of Analyses of covariance support very different call frequency for island population differences in means for forearm lengths was −1.82, groups (F(1, 49) = 704.260, P value = 0.000), but no influence of body 0.422 mm
Fig. 1 Results from IMa2 in A coalescent-based estimator of genetic drift, and acoustic divergence in the Pteronotus parnellii species complex
Fig. 1 Results from IMa2 analyses of Pteronotus parnellii s.l. populations. a Joint posterior density of Ne estimates for island populations. b Divergence time estimates between Puerto Rican and Hispaniolan populations in thousands of years (Ka)
Fig. 3 in A coalescent-based estimator of genetic drift, and acoustic divergence in the Pteronotus parnellii species complex
Fig. 3 Densities of Bayesian posteriors for FST based on betweenpopulation migration rates, and PST for relevant phenotypic variables (Brommer et al. 2014). The lines show the 95th percentile for the corresponding FST, and the 5% percentile for the PST. The overlap between PST body mass and FST Hispaniola was 0.023, for FST Puerto Rico it was 0.084; between PST call frequency and FST Hispaniola was <0.001, for FST Puerto Rico it was 0.003; and between PST forearm length and FST Hispaniola was 0.049, for FST Puerto Rico it was 0.125
Genetic diversity, structure, and demography of Pandanus boninensis(Pandanaceae) with sea drifted seeds, endemic to the Ogasawara Islands of Japan: Comparison between young and old islands
Open the record for dataset details and reuse information.
Data for: Harvest and decimation affect genetic drift and the effective population size in wild reindeer
Open the record for dataset details and reuse information.
Data from: Drift happens: molecular genetic diversity and differentiation among populations of jewelweed (Impatiens capensis Meerb.) reflect fragmentation of floodplain forests
Open the record for dataset details and reuse information.
Data from: A coalescent-based estimator of genetic drift, and acoustic divergence in the Pteronotus parnellii species complex
Determining the processes responsible for phenotypic variation is one of the central tasks of evolutionary biology. While the importance of acoustic traits for foraging and communication in echolocating mammals suggests adaptation, the seldom-tested null hypothesis to explain trait divergence is genetic drift. Here we derive FST values from multi-locus coalescent isolation-with-migration models, and couple them with estimates of quantitative trait divergence, or PST, to test drift as the evolutionary process responsible for phenotypic divergence in island populations of the Pteronotus parnellii species complex. Compared to traditional comparisons of PST to FST, the migration-based estimates of FST are unidirectional instead of bidirectional, simultaneously integrate variation among loci and individuals, and posterior densities of PST and FST can be compared directly. We found the evolution of higher call frequencies is inconsistent with genetic drift for the Hispaniolan population, despite many generations of isolation from its Puerto Rican counterpart. While the Hispaniolan population displays dimorphism in call frequencies, the higher frequency of the females is incompatible with sexual selection. Instead, cultural drift toward higher frequencies among Hispaniolan females might explain the divergence. By integrating Bayesian coalescent and trait analyses, this study demonstrates a powerful approach to testing genetic drift as the default evolutionary mechanism of trait differentiation between populations.
Evidence that genetic drift not adaptation drives fast-Z and large-Z effects in Ficedula flycatchers
<p>The sex chromosomes have been hypothesized to play a key role in driving adaptation and speciation across many taxa. The reason for this is thought to be the hemizygosity of the heteromorphic part of sex chromosomes in the heterogametic sex, which exposes recessive mutations to natural and sexual selection. The exposure of recessive beneficial mutations increases their rate of fixation on the sex chromosomes, which results in a faster rate of evolution. In addition, genetic incompatibilities between sex-linked loci are exposed faster in the genomic background of hybrids of divergent lineages, which makes sex chromosomes contribute disproportionately to reproductive isolation. However, in birds, which show a Z/W sex determination system, the role of adaptation vs. genetic drift as the driving force of the faster differentiation of the Z chromosome (<em>fast-Z</em> effect) and the disproportionate role of the Z chromosome in reproductive isolation (<em>large-Z</em> effect) are still debated. Here, we address this debate in the bird genus <em>Ficedula</em> flycatchers based on population-level whole-genome sequencing data of six species. Our analysis provides evidence for both faster lineage sorting and reduced gene flow on the Z chromosome than the autosomes. However, these patterns appear to be driven primarily by the increased role of genetic drift on the Z chromosome, rather than an increased rate of adaptive evolution. Genomic scans of selective sweeps and fixed differences in fact suggest a reduced action of positive selection on the Z-chromosome. Nevertheless, it is possible that the faster lineage sorting of the Z chromosome due to genetic drift may help drive the evolution of genetic incompatibilities between species.</p>
Archived data for: Balancing selection, genetic drift, and human mediated-introgression interplay to shape MHC (functional) diversity in Mediterranean brown trout
<p>The extraordinary polymorphism of Major Histocompatibility Complex (MHC) genes is considered a paradigm of pathogen-mediated balancing selection, although empirical evidence is still scarce. Furthermore, the relative contribution of balancing selection to shape MHC population structure and diversity, compared to that of neutral forces, as well as its interaction with other evolutionary processes such as hybridization, remains largely unclear. To investigate these issues, we analysed adaptive (MHC-DAB gene) and neutral (11 microsatellite loci) variation in 156 brown trout (<i>Salmo trutta </i>complex) from six wild populations in central Italy exposed to introgression from domestic hatchery lineages (assessed with the LDH gene). MHC diversity and structuring correlated with those at microsatellites, indicating the substantial role of neutral forces. However, individuals carrying locally rare MHC alleles/supertypes (regardless of the zygosity status and degree of sequence dissimilarity of MHC) were in better body condition (a proxy of individual fitness/parasite load), hence supporting balancing selection under rare allele advantage, but not heterozygote advantage or divergent allele advantage. The association between specific MHC supertypes and body condition confirmed in part this finding. Across populations, MHC allelic richness increased with increasing admixture between native and domestic lineages, indicating introgression as a source of MHC variation. Furthermore, introgression across populations appeared more pronounced for MHC than microsatellites, possibly because initially-rare MHC variants are expected to introgress more readily under rare allele advantage. Providing evidence for the complex interplay among neutral evolutionary forces, balancing selection and human-mediated introgression in shaping the pattern of MHC (functional) variation, our findings contribute to a deeper understanding of the evolution of MHC genes in wild populations exposed to anthropogenic disturbance.</p>
Complex patterns shape immune genes diversity during invasion of common raccoon in Europe – selection in action despite genetic drift
<p>Rapid adaptation is common in invasive populations and is crucial to their long-term success. The primary target of selection in the invasive species' new range is standing genetic variation. Therefore, genetic drift and natural selection acting on existing variation are key evolutionary processes through which invaders will evolve over a short timescale. In this study, we used the case of the raccoon <em>Procyon</em> <em>lotor</em> invasion in Europe to identify the forces shaping the diversity of immune genes during invasion. The genes involved in the defence against infection should be under intense selection pressure in the invasive range where novel pathogens are expected to occur. To disentangle the selective and demographic processes shaping the adaptive immune diversity of its invasive and expanding populations, we have developed species-specific SNP markers located in the coding regions of targeted immune-related genes. We characterised the genetic diversity of 110 functionally important immune genes in two invasive and one native raccoon genetic clusters, each presenting a different demographic history. Despite the strong effect of demographic processes in the invasive clusters, we detected a subset of genes exhibiting the diversity pattern suggestive of selection. The most likely process shaping the variation in those genes was balancing selection. The selected genes belong to toll-like receptors and cytokine-related genes. Our results suggest that the prevalence of selection depends on the level of diversity, i.e. – less genetically diverse invasive population from Czech Republic displayed fewer signs of selection. Our results highlight the role of standing genetic variation in adapting to a new environment. Understanding the evolutionary mechanisms behind invasion success would enable predicting how populations may respond to environmental change.</p>
Reference genome resources associated with the project: Functional genetic diversity is correlated with intensity of genetic drift in populations of an endangered rattlesnake
<p class="MsoNormal">Theory predicts that genetic erosion in small, isolated populations of endangered species can be assessed using estimates of neutral genetic variation reflecting long-term impacts of genetic drift, yet this widely used approach has been questioned in the genomics era. Here we leverage a chromosome-level assembly and whole genome resequencing data (N=110 individuals) from an endangered rattlesnake (<em>Sistrurus catenatus</em>) to evaluate the relationship between genome-wide neutral and functional diversity over long- and short-term timescales. As predicted for populations at long-term equilibrium, we found a positive correlation between population-level estimates of neutral genetic diversity (π) and the mean number of highly detrimental loss-of-function mutations, and a negative relationship between neutral genetic diversity and an estimate of genetic load. In contrast, we found only a weak, non-significant positive correlation between levels of neutral and adaptive variation. Additional analyses using estimates of drift at more recent time scales (> 100 generations) show expected correlations between both measures of genetic load, but a lack of a significant correlation with levels of adaptive variation. Individual-based demographic metrics that capture drift impacts over recent time scales confirm these results. Broadly, our results confirm that estimates of diversity and demography based on neutral genetic variation provide an accurate measure of a key component of genetic erosion – genetic load – in populations of a threatened vertebrate. Our findings also provide nuance to the neutral-functional diversity controversy by demonstrating that neutral genetic diversity is useful in predicting some, but not all, components of functional genetic diversity.</p>
Data from: Do chromosome rearrangements fix by genetic drift or natural selection? Insights from Brenthis butterflies
<p>Large-scale chromosome rearrangements, such as fissions and fusions, are a common feature of eukaryote evolution. They can have considerable influence on the evolution of populations, yet it remains unclear exactly how rearrangements become established and eventually fix. Rearrangements could fix by genetic drift if they are weakly deleterious or neutral, or they may instead be favoured by positive natural selection. Here we compare genome assemblies of three closely related <em>Brenthis</em> butterfly species and characterise a complex history of fission and fusion rearrangements. An inferred demographic history of these species suggests that rearrangements became fixed in populations with large long-term effective size (<em>N<sub>e</sub></em>). However, we also find large runs of homozygosity within individual genomes and show that a model of population structure with smaller local <em>N<sub>e</sub></em> can reconcile these observations. Using a recently developed analytic framework for characterising hard selective sweeps, we find that chromosome fusions are not enriched for evidence of past sweeps compared to other regions of the genome. Nonetheless, one chromosome fusion in the <em>B. daphne</em> genome is associated with a valley of diversity where genealogical branch lengths are distorted, consistent with a selective sweep. Our results suggest that drift is a stronger force in these populations than suggested by overall genetic diversity, but that the fixation of strongly underdominant rearrangements remains unlikely. Additionally, although chromosome fusions do not typically exhibit signatures of selective sweeps, a single example raises the possibility that natural selection may sometimes play a role in their fixation.</p>
Evidence that genetic drift not adaptation drives fast-Z and large-Z effects in Ficedula flycatchers
Open the record for dataset details and reuse information.
Genetic drift does not sufficiently explain patterns of electric signal variation among populations of the mormyrid electric fish Paramormyrops kingsleyae
Open the record for dataset details and reuse information.
Complex patterns shape immune genes diversity during invasion of common raccoon in Europe – selection in action despite genetic drift
Open the record for dataset details and reuse information.
Data from: Do chromosome rearrangements fix by genetic drift or natural selection? Insights from Brenthis butterflies
Open the record for dataset details and reuse information.
Data from: A coalescent-based estimator of genetic drift, and acoustic divergence in the Pteronotus parnellii species complex
Open the record for dataset details and reuse information.
Reference genome resources associated with the project: Functional genetic diversity is correlated with intensity of genetic drift in populations of an endangered rattlesnake
Open the record for dataset details and reuse information.
ScienceDex guides
Understand access before you commit
These curated guides explain access requirements, typical timelines, costs, and reuse considerations for widely used research datasets.
Allen Brain Atlas
Allen Brain Atlas is an Allen Institute collection of brain map atlases, datasets, APIs, and analysis tools covering mouse, human, and non-human primate brain resources.
Annotated Behaviour and Observability Dataset (ABODe)
ABODe is a University of Edinburgh DataShare dataset for behavior classification in group-housed mice using home-cage video, identities, bounding boxes, ground-plate positions, and annotator labels.
DANDI Archive for NWB datasets
DANDI is a BRAIN Initiative archive for publishing and sharing neurophysiology data, including electrophysiology, optophysiology, and behavioral data packaged as NWB and related standards.
International Brain Laboratory public data
The International Brain Laboratory public data releases expose standardized mouse decision-making experiments, including Neuropixels recordings, widefield calcium imaging, behavior, and session metadata accessed through the ONE API.
OpenNeuro
OpenNeuro is a free, open platform for sharing neuroimaging datasets, with public search, dataset pages, and download paths for web, S3, DataLad, and the OpenNeuro CLI.