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1,456 results for “parallelism”

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Data from: Molecular phenotyping of maternally mediated parallel adaptive divergence within Rana arvalis and Rana temporaria

When similar selection acts on the same traits in multiple species or populations, parallel evolution can result in similar phenotypic changes, yet the underlying molecular architecture of parallel phenotypic divergence can be variable. Maternal effects can influence evolution at ecological timescales and facilitate local adaptation, but their contribution to parallel adaptive divergence is unclear. In this study, we (i) tested for variation in embryonic acid tolerance in a common garden experiment and (ii) used molecular phenotyping of egg coats to investigate the molecular basis of maternally mediated parallel adaptive divergence in two amphibian species (Rana arvalis and Rana temporaria). Our results on three R. arvalis and two R. temporaria populations show that adaptive divergence in embryonic acid tolerance is mediated via maternally derived egg coats in both species. We find extensive polymorphism in egg jelly coat glycoproteins within both species and that acid-tolerant clutches have more negatively charged egg jelly – indicating that the glycosylation status of the jelly coat proteins is under divergent selection in acidified environments, likely due to its impact on jelly water balance. Overall, these data provide evidence for parallel mechanisms of adaptive divergence in two species. Our study highlights the importance of studying intraspecific molecular variation in egg coats and, specifically, their glycoproteins, to increase understanding of underlying forces maintaining variation in jelly coats.

opencc-zeroDec 2015View details →
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Data from: Parallel signatures of selection at genomic islands of divergence and the major histocompatibility complex in ecotypes of sockeye salmon across Alaska

Understanding the genetic mechanisms that facilitate adaptive radiation is an important component of evolutionary biology. Here, we genotyped 82 neutral SNPs, seven SNPs in islands of divergence identified in a previous study (island SNPs), and a region of the major histocompatibility complex (MHC) in 32 populations of sockeye salmon to investigate whether conserved genes and genomic regions are involved in adaptive radiation. Populations representing three ecotypes were sampled from seven drainages with differing habitats and colonization histories spanning a range of 2,000 km. We found strong signatures of parallel selection across drainages at the island SNPs and MHC, suggesting that the same loci undergo divergent selection during adaptive radiation. However, patterns of differentiation at most island SNPs and the MHC were not associated with ecotypes, suggesting that these loci are responding differently to a mosaic of selective pressures. Our study provides some of the first evidence that conserved genomic islands may be involved in adaptive divergence of salmon populations. Additionally, our data provide further support for the hypothesis that sockeye salmon inhabiting rivers unconnected to lakes harbor similar genetic diversity across large distances, are likely the ancestral form of the species, and have repeatedly recolonized lake systems as they have become available after glacial recession. Finally, our results highlight the value and importance of validating outlier loci by screening additional populations and regions, a practice that will hopefully become more common in the future.

opencc-zeroDec 2018View details →
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Data from: A parallel population genomic and hydrodynamic approach to fishery management of highly-dispersive marine invertebrates: the case of the Fijian black-lip pearl oyster Pinctada margaritifera

Fishery management and conservation of marine species increasingly relies on genetic data to delineate biologically relevant stock boundaries. Unfortunately for high gene flow species which may display low, but statistically significant population structure, there is no clear consensus on the level of differentiation required to resolve distinct stocks. The use of fine-scale neutral and adaptive variation, considered together with environmental data can offer additional insights to this problem. Genome-wide genetic data (4,123 SNPs), together with an independent hydrodynamic particle dispersal model were used to inform farm and fishery management in the Fijian black-lip pearl oyster Pinctada margaritifera, where comprehensive fishery management is lacking, and the sustainability of exploitation uncertain. Weak fine-scale patterns of population structure were detected, indicative of broad-scale panmixia among wild oysters, while a hatchery-sourced farmed population exhibited a higher degree of genetic divergence (Fst = 0.0850–0.102). This hatchery-produced population had also experienced a bottleneck (NeLD = 5.1; 95% C.I. = [5.1–5.3]); compared to infinite NeLD estimates for all wild oysters. Simulation of larval transport pathways confirmed the existence of broad-scale mixture by surface ocean currents, correlating well with fine-scale patterns of population structuring. Fst outlier tests failed to detect large numbers of loci supportive of selection, with 2–5 directional outlier SNPs identified (average Fst = 0.116). The lack of biologically significant population genetic structure, absence of evidence for local adaptation and larval dispersal simulation, all indicate the existence of a single genetic stock of P. margaritifera in the Fiji Islands. This approach using independent genomic and oceanographic tools has allowed fundamental insights into stock structure in this species, with transferability to other highly-dispersive marine taxa for their conservation and management.

opencc-zeroDec 2016View details →
dryad32/100

Data from: Evaluating genomic divergence and parallelism in replicate ecomorphs from young and old cichlid adaptive radiations

Comparative genomic studies of closely related species typically focus on single species pairs at one given stage of divergence. That makes it difficult to infer the continuum of evolutionary process during speciation and beyond. Here, we use whole-genome resequencing to examine genomic patterns of divergence in three sympatric cichlid species pairs with very similar functional and ecological differentiation, but different ages. We find a strong signature of increasing genomic divergence with time in both the mitochondrial genome and the nuclear genome. In contrast to many other systems, we find that in these cichlids regions of elevated relative differentiation also exhibit increased absolute differentiation. We detect a signature of convergent evolution in a comparison of outlier regions across all three species pair comparisons but the extent of it is modest, and regions that are strongly divergent in any one pair tend to be only slightly elevated in the other pairs, consistent with a repeatable but polygenic basis of traits that characterize the ecomorphs. Our results suggest that strong functional phenotypic differentiation, as seen in all three species pairs, is generally associated with a clear signature of genomic divergence, even in the youngest species pair.

opencc-zeroDec 2014View details →
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Excessive parallelism in protein evolution of Lake Baikal amphipod species flock

Repeated emergence of similar adaptations is often explained by parallel evolution of underlying genes. However, evidence of parallel evolution at amino acid level is limited. When the analyzed species are highly divergent, this can be due to epistasic interactions underlying the dynamic nature of the amino acid preferences: the same amino acid substitution may have different phenotypic effects on different genetic backgrounds. Distantly related species also often inhabit radically different environments, which makes the emergence of parallel adaptations less likely. Here, we hypothesize that parallel molecular adaptations are more prevalent between closely related species. We analyze the rate of parallel evolution in genome-size sets of orthologous genes in three groups of species with widely ranging levels of divergence: 47 species of the relatively recent lake Baikal amphipod radiation, a species flock of very closely related cichlids, and a set of significantly more divergent vertebrates. In genes of amphipods, the rate of parallel substitutions at nonsynonymous sites exceeded that at synonymous sites, suggesting rampant selection driving parallel adaptation. By contrast, in cichlids, the rate of nonsynonymous parallel evolution nearly equalled that at synonymous sites, while in vertebrates, this rate was lower than that at synonymous sites, indicating the role of drift in fixation of parallel substitutions. Further data is needed to clarify the cause of the excessive parallelism observed in gammarids.

opencc-zeroJan 2020View details →
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Data from: Parallel evolution of local adaptation and reproductive isolation in the face of gene flow

Parallel evolution of similar phenotypes provides strong evidence for the operation of natural selection. Where these phenotypes contribute to reproductive isolation, they further support a role for divergent, habitat-associated selection in speciation. However, the observation of pairs of divergent ecotypes currently occupying contrasting habitats in distinct geographical regions is not sufficient to infer parallel origins. Here we show striking parallel phenotypic divergence between populations of the rocky-shore gastropod, Littorina saxatilis, occupying contrasting habitats exposed to either wave action or crab predation. This divergence is associated with barriers to gene exchange but, nevertheless, genetic variation is more strongly structured by geography than by ecotype. Using approximate Bayesian analysis of sequence data and AFLP markers, we show that the ecotypes are likely to have arisen in the face of continuous gene flow and that the demographic separation of ecotypes has occurred in parallel at both regional and local scales. Parameter estimates suggest a long delay between colonisation of a locality and ecotype formation, perhaps because the postglacial spread of crab populations was slower than the spread of snails. Adaptive differentiation may not be fully genetically independent despite being demographically parallel. These results provide new insight into a major model of ecologically-driven speciation.

opencc-zeroNov 2013View details →
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Data from: Parallel allochronic divergence in a winter moth due to disruption of reproductive period by winter harshness

The disruption of reproductive timing by climatic harshness may result in the temporal isolation of conspecific populations and, ultimately, in speciation. However, whether temporal isolation alone can act as the force initiating speciation and how often the same type of climatic disruption results in the divergence of allochronic populations in a lineage is largely unknown. The reproductive period of the winter geometrid moth Inurois punctigera is separated into early and late winter in habitats with severe winters, but not in habitats with mild winters, suggesting that the reproductive season is disrupted by the harshness of the mid-winter period. Here, we show that sympatric pairs of early- and late-winter populations that differ in origin exist in different regions, suggesting a parallel divergence of reproductive timing. In each region, significant genetic differentiation exists between these early- and late-winter populations, suggesting that the temporal reproductive isolation has persisted. Moreover, we demonstrate that the temporal isolation, in comparison with geographic isolation, contributes greatly to the genetic differentiation among geographic and temporal populations by an analysis of molecular variances and a comparison of genetic differentiations (Fst) between geographic populations with and without difference in reproductive season. Thus, adaptive divergence of allochronically reproducing populations occurred independently in different regions, implying the generality of speciation by temporal isolation in a winter moth lineage.

opencc-zeroDec 2010View details →
dryad32/100

Data from: Parallel tagged next-generation sequencing on pooled samples – a new approach for population genetics in ecology and conservation

Next-generation sequencing (NGS) on pooled samples has already been broadly applied in human medical diagnostics and plant and animal breeding. However, thus far it has been only sparingly employed in ecology and conservation, where it may serve as a useful diagnostic tool for rapid assessment of species genetic diversity and structure at the population level. Here we undertake a comprehensive evaluation of the accuracy, practicality and limitations of parallel tagged amplicon NGS on pooled population samples for estimating species population diversity and structure. We obtained 16S and Cyt b data from 20 populations of Leiopelma hochstetteri, a frog species of conservation concern in New Zealand, using two approaches – parallel tagged NGS on pooled population samples and individual Sanger sequenced samples. Data from each approach were then used to estimate two standard population genetic parameters, nucleotide diversity (π) and population differentiation (FST), that enable population genetic inference in a species conservation context. We found a positive correlation between our two approaches for population genetic estimates, showing that the pooled population NGS approach is a reliable, rapid and appropriate method for population genetic inference in an ecological and conservation context. Our experimental design also allowed us to identify both the strengths and weaknesses of the pooled population NGS approach and outline some guidelines and suggestions that might be considered when planning future projects.

opencc-zeroDec 2012View details →
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Data from: Phylogeography of the prickly sculpin (Cottus asper) in north-western North America reveals parallel phenotypic evolution across multiple coastal–inland colonizations

Aim: Glacial cycles during the Pleistocene may have frequently contributed to parallel evolution of phenotypes across independently evolving genetic lineages associated with separate glacial refugia. Previous studies based on morphology suggested that the prickly sculpin (Cottus asper) survived the Last Glacial Maximum (LGM) in southern coastal and inland refugia, favouring allopatric divergence between coastal and inland prickling phenotypes, which vary in the degree to which spine-like scales cover the body of the fish. Herein, we aimed to test whether parallel evolution across multiple genetic lineages rather than a single-lineage origin of highly prickled inland sculpins could serve as an explanation for the biogeographical distribution of prickling phenotypes. Location: North-western North America, Southeast Alaska and Canada (British Columbia). Methods: We used data from mitochondrial haplotypes and 19 microsatellite loci to identify distinct genetic lineages as a basis to interpret patterns of phenotypic evolution. Results: The occurrence of multiple mtDNA groups suggests that highly prickled inland phenotypes comprise more than one genetic lineage. Both mtDNA and microsatellite data are consistent with post-glacial dispersal along the coast and repeated coastal to inland colonization events, as opposed to inland dispersal of a single lineage from a southern refugium to northern regions. Main conclusions: Our results suggest that highly prickled inland phenotypes evolved repeatedly following multiple inland colonization events, probably via coastal rivers. The prickly sculpin therefore provides an example of recent (post-glacial) parallel evolution, potentially facilitated by standing genetic variation already present in the ancestral coastal populations.

opencc-zeroDec 2014View details →
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Data from: Parallel genomic architecture underlies repeated sexual signal divergence in Hawaiian Laupala crickets

When the same phenotype evolves repeatedly, we can explore the predictability of genetic changes underlying phenotypic evolution. Theory suggests that genetic parallelism is less likely when phenotypic changes are governed by many small-effect loci compared to few of major effect, because different combinations of genetic changes can result in the same quantitative outcome. However, some genetic trajectories might be favoured over others, making a shared genetic basis to repeated polygenic evolution more likely. To examine this, we studied the genetics of parallel male mating song evolution in the Hawaiian cricket <i>Laupala</i>. We compared quantitative trait loci (QTL) underlying song divergence in three species pairs varying in phenotypic distance. We tested whether replicated song divergence between species involves the same QTL and the likelihood that sharing QTL is related to phenotypic effect sizes. Contrary to theoretical predictions, we find substantial parallelism in polygenic genetic architectures underlying repeated song divergence. QTL overlapped more than expected based on simulated QTL analyses. Interestingly, QTL effect size did not predict QTL sharing, but did correlate with magnitude of phenotypic divergence. We highlight potential mechanisms driving these constraints on cricket song evolution and discuss a scenario that consolidates empirical quantitative genetic observations with micro-mutational theory.

opencc-zeroSep 2019View details →
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Data from: Ancestral gene flow and parallel organellar genome capture result in extreme phylogenomic discord in a lineage of angiosperms

While hybridization has recently received a resurgence of attention from systematists and evolutionary biologists, there remains a dearth of case studies on ancient, diversified hybrid lineages-clades of organisms that originated through reticulation. Studies on these groups are valuable in that they would speak to the long-term phylogenetic success of lineages following gene flow between species. We present a phylogenomic view of Heuchera, long known for frequent hybridization, incorporating all three independent genomes: targeted nuclear (~400,000 bp), plastid (~160,000 bp), and mitochondrial (~470,000 bp) data. We analyze these data using multiple concatenation and coalescence strategies. The nuclear phylogeny is consistent with previous work and with morphology, confidently suggesting a monophyletic Heuchera. By contrast, analyses of both organellar genomes recover a grossly polyphyletic Heuchera,consisting of three primary clades with relationships extensively rearranged within these as well. A minority of nuclear loci also exhibit phylogenetic discord; yet these topologies remarkably never resemble the pattern of organellar loci and largely present low levels of discord inter alia. Two independent estimates of the coalescent branch length of the ancestor of Heuchera using nuclear data suggest rare or nonexistent incomplete lineage sorting with related clades, inconsistent with the observed gross polyphyly of organellar genomes (confirmed by simulation of gene trees under the coalescent). These observations, in combination with previous work, strongly suggest hybridization as the cause of this phylogenetic discord.

opencc-zeroDec 2015View details →
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Data from: Evolution of thermal tolerance and its fitness consequences: parallel and non-parallel responses to urban heat islands across three cities

The question of parallel evolution—what causes it, and how common it is—has long captured the interest of evolutionary biologists. Widespread urban development over the last century has driven rapid evolutionary responses on contemporary timescales, presenting a unique opportunity to test the predictability and parallelism of evolutionary change. Here we examine rapid urban evolution in an acorn-dwelling ant species, focusing on the urban heat island signal and the ant's tolerance of these altered urban temperature regimes. Using a common-garden experimental design with acorn ant colonies collected from urban and rural populations in three cities and reared under five temperature treatments in the laboratory, we assessed plastic and evolutionary shifts in the heat and cold tolerance of F1 offspring worker ants. In two of three cities, we found evolved losses of cold tolerance, and compression of thermal tolerance breadth. Results for heat tolerance were more complex: in one city, we found evidence of simple evolved shifts in heat tolerance in urban populations, though in another, the difference in urban and rural population heat tolerance depended on laboratory rearing temperature, and only became weakly apparent at the warmest rearing temperatures. The shifts in tolerance appeared to be adaptive, as our analysis of the fitness consequences of warming revealed that while urban populations produced more sexual reproductives under warmer laboratory rearing temperatures, rural populations produced fewer. Patterns of natural selection on thermal tolerances supported our findings of fitness tradeoffs and local adaptation across urban and rural acorn ant populations, as selection on thermal tolerance acted in opposite directions between the warmest and coldest rearing temperatures. Our study provides mixed support for parallel evolution of thermal tolerance under urban temperature rise.

opencc-zeroDec 2017View details →
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Data from: Parallel genetic divergence among coastal-marine ecotype pairs of European anchovy explained by differential introgression after secondary contact

Ecophenotypic differentiation among replicate ecotype pairs within a species complex is often attributed to independent outcomes of parallel divergence driven by adaptation to similar environmental contrasts. However, the extent to which parallel phenotypic and genetic divergence patterns have emerged independently is increasingly questioned by population genomic studies. Here, we document the extent of genetic differentiation within and among two geographic replicates of the coastal and marine ecotypes of the European anchovy (Engraulis encrasicolus) gathered from Atlantic and Mediterranean locations. Using a genome-wide data set of RAD-derived SNPs, we show that habitat type (marine vs. coastal) is the most important component of genetic differentiation among populations of anchovy. By analysing the joint allele frequency spectrum of each coastal-marine ecotype pair, we show that genomic divergence patterns between ecotypes can be explained by a postglacial secondary contact following a long period of allopatric isolation (c. 300 kyrs). We found strong support for a model including heterogeneous migration among loci, suggesting that secondary gene flow has eroded past differentiation at different rates across the genome. Markers experiencing reduced introgression exhibited strongly correlated differentiation levels among Atlantic and Mediterranean regions. These results support that partial reproductive isolation and parallel genetic differentiation among replicate pairs of anchovy ecotypes are largely due to a common divergence history prior to secondary contact. They moreover provide comprehensive insights into the origin of a surprisingly strong fine-scale genetic structuring in a high gene flow marine fish, which should improve stock management and conservation actions.

opencc-zeroDec 2015View details →
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Data from: Genomic clustering of adaptive loci during parallel evolution of an Australian wildflower

The buildup of the phenotypic differences that distinguish species has long intrigued biologists. These differences are often inherited as stable polymorphisms that allow the co-segregation of adaptive variation within species, and facilitate the differentiation of complex phenotypes between species. It has been suggested that the clustering of adaptive loci could facilitate this process but evidence is still scarce. Here we used QTL analysis to study the genetic basis of phenotypic differentiation between coastal populations of the Australian wildflower Senecio lautus. We found that a genomic region consistently governs variation in several of the traits that distinguish these contrasting forms. Additionally, some of the taxon specific traits controlled by this QTL cluster have evolved repeatedly during the adaptation to the same habitats, suggesting that it could mediate divergence between locally adapted forms. This cluster contains footprints of divergent natural selection across the range of S. lautus, which suggests that it could have been instrumental for the rapid diversification of this species.

opencc-zeroDec 2016View details →
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Data from: Parallels between two geographically and ecologically disparate cave invasions by the same species, Asellus aquaticus (Isopoda, Crustacea)

Caves are long-known examples of evolutionary replications where similar morphologies (troglomorphies) evolve independently as the result of strong natural selection of the extreme environment. Recently, this paradigm has been challenged based on observations that troglomorphies are inconsistent across taxa and different subterranean habitats. We investigated the degree of replicated phenotypic change in two independent cave invasions by the freshwater isopod Asellus aquaticus; the first in a sulphidic aquifer in Romania, the second in a sinking river in the Dinaric Karst in Slovenia. Both ancestral surface populations still live alongside the subterranean ones. Phylogenetic analyses show independence of the two colonization events, and microsatellite analysis shows no evidence of ongoing genetic exchange between surface and subterranean ecomorphs. The overall morphology has changed dramatically at both sites (50 of 62 morphometric traits). The amount of phenotypic change did not reflect differences in genetic diversity between the two ancestral populations. Multivariate analyses revealed divergent evolution in caves, not parallel or convergent as predicted by the current paradigm. Still, 18 traits changed in a parallel fashion, including eye and pigment loss and antennal elongation. These changes might be a consequence of darkness as the only common ecological feature, because Romanian caves are chemoautotrophic and rich in food, whereas Slovenian caves are not. Overall, these results show that morphologically alike surface populations can diverge after invading different subterranean habitats, and that only about one-third of all changing traits behave as troglomorphies in the traditional sense.

opencc-zeroDec 2014View details →
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Data from: Parallel polyploid speciation: distinct sympatric gene-pools of recurrently derived allo-octoploid Asplenium ferns

Although polyploidy is widespread, its significance to the generation of biodiversity remains unclear. Many polyploids have been derived recurrently. For a particular polyploid, gene-flow between the products of independent origin is typical where they come into contact. Here, we use AFLP DNA-fingerprinting and chloroplast DNA sequences to demonstrate parallel polyploid speciation within both of the ferns Asplenium cimmeriorum and A. gracillimum. Both of these taxa comprise at least two allopolyploids, recurrently derived from the same progenitor pair. Each of these allopolyploids remain genetically distinguishable even with extensive sympatry, and could therefore be considered distinct species. To our knowledge, parallel speciation on this scale amongst recurrent polyploids has not been previously reported. With their parallel origins, these 'evolutionary replicates' provide an unrivalled opportunity to investigate how the reproductive barriers and ecological differentiation necessary for speciation arise following polyploidy.

opencc-zeroDec 2009View details →
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Data from: Modern spandrels: the roles of genetic drift, gene flow and natural selection in the formation of parallel clines

Urban environments offer the opportunity to study the role of adaptive and non-adaptive evolutionary processes on an unprecedented scale. While the presence of parallel clines in heritable phenotypic traits is often considered strong evidence for the role of natural selection, non-adaptive evolutionary processes can also generate clines, and this may be more likely when traits have a non-additive genetic basis due to epistasis. In this paper, we use spatially-explicit simulations modelled according to the cyanogenesis (HCN) polymorphism in white clover (Trifolium repens) to examine the formation of phenotypic clines along urbanization gradients under varying levels of drift, gene flow and selection. HCN results from an epistatic interaction between two Mendelian-inherited loci. Our results demonstrate that the genetic architecture of this trait makes natural populations susceptible to decreases in HCN frequencies via drift. Gradients in the strength of drift across a landscape resulted in phenotypic clines with lower frequencies of HCN in strongly drifting populations, giving the misleading appearance of deterministic adaptive changes in the phenotype. Studies of heritable phenotypic change in urban populations should generate null models of phenotypic evolution based on the genetic architecture underlying focal traits prior to invoking selection's role in generating adaptive differentiation.

opencc-zeroDec 2017View details →
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Data from: Species tree estimation of North American chorus frogs (Hylidae: Pseudacris) with parallel tagged amplicon sequencing

The field of phylogenetics is changing rapidly with the application of high-throughput sequencing to non-model organisms. Cost-effective use of this technology for phylogenetic studies, which often include a relatively small portion of the genome but several taxa, requires strategies for genome partitioning and sequencing multiple individuals in parallel. In this study we estimated a multilocus phylogeny for the North American chorus frog genus Pseudacris using anonymous nuclear loci that were recently developed using a reduced representation library approach. We sequenced 27 nuclear loci and three mitochondrial loci for 44 individuals on 1/3 of an Illumina MiSeq run, obtaining 96.5% of the targeted amplicons at less than 20% of the cost of traditional Sanger sequencing. We found heterogeneity among gene trees, although four major clades (Trilling Frog, Fat Frog, crucifer, and West Coast) were consistently supported, and we resolved the relationships among these clades for the first time with strong support. We also found discordance between the mitochondrial and nuclear datasets that we attribute to mitochondrial introgression and a possible selective sweep. Bayesian concordance analysis in BUCKy and species tree analysis in *BEAST produced largely similar topologies, although we identify taxa that require additional investigation in order to clarify taxonomic and geographic range boundaries. Overall, we demonstrate the utility of a reduced representation library approach for marker development and parallel tagged sequencing on an Illumina MiSeq for phylogenetic studies of non-model organisms.

opencc-zeroDec 2013View details →
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Data from: Shared and non-shared genomic divergence in parallel ecotypes of Littorina saxatilis at a local scale

Parallel speciation occurs when selection drives repeated, independent adaptive divergence that reduces gene flow between ecotypes. Classical examples show parallel speciation originating from shared genomic variation, but this does not seem to be the case in the rough periwinkle (Littorina saxatilis) that has evolved considerable phenotypic diversity across Europe, including several distinct ecotypes. Small 'wave' ecotype snails inhabit exposed rocks and experience strong wave action, while thick-shelled, 'crab' ecotype snails are larger and experience crab predation on less exposed shores. Crab and wave ecotypes appear to have arisen in parallel and recent evidence suggests only marginal sharing of molecular variation linked to evolution of similar ecotypes in different parts of Europe. However the extent of genomic sharing is expected to increase with gene flow and more recent common ancestry. To test this we used de novo RAD-sequencing to quantify the extent of shared genomic divergence associated with phenotypic similarities among ecotype-pairs on three close islands (&lt; 10 km distance) connected by weak gene flow (Nm~0.03) and with recent common ancestry (&lt; 10,000 years). After accounting for technical issues, including a large proportion of null alleles due to a large effective population size, we found ~8-28% of positive outliers were shared between two islands and ~2-9% were shared among all three islands. This low level of sharing suggests that parallel phenotypic divergence in this system is not matched by shared genomic divergence despite a high probability of gene flow and standing genetic variation.

opencc-zeroDec 2014View details →
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Data from: Protein expression parallels thermal tolerance and ecologic changes in the diversification of a diving beetle species complex

Physiological changes associated with evolutionary and ecological processes such as diversification, range expansion or speciation are still incompletely understood, especially for non-model species. Here we study differences in protein expression in response to temperature in a western Mediterranean diving beetle species complex, using two-dimensional differential gel electrophoresis with one Moroccan and one Iberian population each of Agabus ramblae and Agabus brunneus. We identified proteins with significant expression differences after thermal treatments comparing them with a reference EST library generated from one of the species of the complex (A. ramblae). The colonisation during the Middle Pleistocene of the Iberian peninsula by A. ramblae, where maximum temperatures and seasonality are lower than in the ancestral north African range, was associated with changes in the response to 27 °C in proteins related to energy metabolism. The subsequent speciation of A. brunneus from within populations of Iberian A. ramblae was associated with changes in the expression of several stress-related proteins (mostly chaperons) when exposed to 4 °C. These changes are in agreement with the known tolerance to lower temperatures of A. brunneus, which occupies a larger geographical area with a wider range of climatic conditions. In both cases, protein expression changes paralleled the evolution of thermal tolerance and the climatic conditions experienced by the species. However, although the colonisation of the Iberian peninsula did not result in morphological change, the speciation process of A. brunneus within Iberia involved genetic isolation and substantial differences in male genitalia and body size and shape.

opencc-zeroDec 2014View details →

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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.

allen-brain-atlas
neuroscienceopenDocumentation, web resources, and API references are available online.
Last verified 2026-04-30Open record

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.

abode-home-cage
behavioral-neuroscienceopenThe DataShare record exposes download links for annotations, documentation, license text, and the zipped per-snippet data directory.
Last verified 2026-04-30Open record

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.

dandi-nwb
electrophysiologyopenPublished Dandiset metadata and archive endpoints are available through the production DANDI API.
Last verified 2026-04-30Open record

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.

ibl
behavioral-neuroscienceopenPublic sessions can be searched and loaded from the IBL public data server through ONE.
Last verified 2026-04-29Open record

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.

openneuro
neuroscienceopenPublished datasets are available on demand over the internet.
Last verified 2026-04-29Open record